adapted to Kick Assembler, some documentation update

2019-09-07 12:35:21 +02:00
1 parent ae23dbae7b
commit de27124b4f
@@ -2,9 +2,9 @@
 # Compilation related files
 temp.s
-temp.map
+temp.sym
-ophis.bin
+assembler/KickAss*
 build/*
 # Input to the similarity tool - copyrighted material, we can't check it in!
@@ -1,3 +0,0 @@
 [submodule "Ophis"]
 	path = Ophis
 	url = https://github.com/gardners/Ophis.git
@@ -33,15 +33,10 @@ GIT_COMMIT:= $(shell git log -1 --pretty='%h' | tr '[:lower:]' '[:upper:]')
 all: build/chargen build/newkern_generic build/newbasic_generic build/newc65 build/newkern_ultimate64 build/newbasic_ultimate64
 Ophis:
 	git submodule init
 	git submodule update
 clean:
 	@rm -rf build
 	@rm -f temp.s
-	@rm -f temp.map
+	@rm -f temp.sym
 	@rm -f ophis.bin
 updatebin: build/chargen build/newbasic_generic build/newkern_generic build/newbasic_mega65 build/newkern_mega65 build/newbasic_ultimate64 build/newkern_ultimate64
 	cp build/chargen                  bin/chargen.rom
@@ -81,23 +76,23 @@ build/chargen: $(TOOL_PNGPREPARE) assets/8x8font.png
 # Dependencies
-build/basic_generic/OUT.BIN:  Ophis $(TOOLS_LIST) $(SRC_BASIC_generic) build/basic/packed_messages.s
+build/basic_generic/OUT.BIN:      $(TOOLS_LIST) $(SRC_BASIC_generic) build/basic/packed_messages.s
-build/kernal_generic/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_KERNAL_generic)
+build/kernal_generic/OUT.BIN:     $(TOOLS_LIST) $(SRC_KERNAL_generic)
-build/newrom_generic:   build/basic_generic/OUT.BIN build/kernal_generic/OUT.BIN
+build/newrom_generic:             build/basic_generic/OUT.BIN build/kernal_generic/OUT.BIN
-build/newkern_generic:  build/newrom_generic Makefile
+build/newkern_generic:            build/newrom_generic Makefile
-build/newbasic_generic: build/newrom_generic Makefile
+build/newbasic_generic:           build/newrom_generic Makefile
-build/basic_mega65/OUT.BIN:  Ophis $(TOOLS_LIST) $(SRC_BASIC_mega65) build/basic/packed_messages.s
+build/basic_mega65/OUT.BIN:       $(TOOLS_LIST) $(SRC_BASIC_mega65) build/basic/packed_messages.s
-build/kernal_mega65/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_KERNAL_mega65)
+build/kernal_mega65/OUT.BIN:      $(TOOLS_LIST) $(SRC_KERNAL_mega65)
-build/newrom_mega65:   build/basic_mega65/OUT.BIN build/kernal_mega65/OUT.BIN
+build/newrom_mega65:              build/basic_mega65/OUT.BIN build/kernal_mega65/OUT.BIN
-build/newkern_mega65:  build/newrom_mega65 Makefile
+build/newkern_mega65:             build/newrom_mega65 Makefile
-build/newbasic_mega65: build/newrom_mega65 Makefile
+build/newbasic_mega65:            build/newrom_mega65 Makefile
-build/basic_ultimate64/OUT.BIN:  Ophis $(TOOLS_LIST) $(SRC_BASIC_ultimate64) build/basic/packed_messages.s
+build/basic_ultimate64/OUT.BIN:   $(TOOLS_LIST) $(SRC_BASIC_ultimate64) build/basic/packed_messages.s
-build/kernal_ultimate64/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_KERNAL_ultimate64)
+build/kernal_ultimate64/OUT.BIN:  $(TOOLS_LIST) $(SRC_KERNAL_ultimate64)
-build/newrom_ultimate64:   build/basic_ultimate64/OUT.BIN build/kernal_ultimate64/OUT.BIN
+build/newrom_ultimate64:          build/basic_ultimate64/OUT.BIN build/kernal_ultimate64/OUT.BIN
-build/newkern_ultimate64:  build/newrom_ultimate64 Makefile
+build/newkern_ultimate64:         build/newrom_ultimate64 Makefile
-build/newbasic_ultimate64: build/newrom_ultimate64 Makefile
+build/newbasic_ultimate64:        build/newrom_ultimate64 Makefile
 # Rules - BASIC and KERNAL
@@ -107,7 +102,7 @@ build/basic/packed_messages.s: $(TOOL_COMPRESS_TEXT)
 	$(TOOL_COMPRESS_TEXT) > build/basic/packed_messages.s
 .PRECIOUS: build/basic_%/OUT.BIN
-build/basic_%/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_BASIC_$*) build/basic/packed_messages.s
+build/basic_%/OUT.BIN: $(TOOLS_LIST) $(SRC_BASIC_$*) build/basic/packed_messages.s
 	@mkdir -p build/basic_$*
 	@rm -f build/basic_$*/*
 	@for SRC in $(SRC_BASIC_$*); do \
@@ -117,7 +112,7 @@ build/basic_%/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_BASIC_$*) build/basic/packed_me
 	$(TOOL_PREPROCESS) -d build/basic_$* -l a000 -h e4d2
 .PRECIOUS: build/kernal_%/OUT.BIN
-build/kernal_%/OUT.BIN: Ophis $(TOOLS_LIST) $(SRC_KERNAL_$*)
+build/kernal_%/OUT.BIN: $(TOOLS_LIST) $(SRC_KERNAL_$*)
 	@mkdir -p build/kernal_$*
 	@rm -f build/kernal_$*/*
 	@for SRC in $(SRC_KERNAL_$*); do \
@@ -1,5 +1,6 @@
 # open-roms
-A project to create unencumbered open-source ROMs for use on selected retro computers
+
 A project to create unencumbered open-source ROMs for use on selected retro computers. For the current status check [this document](STATUS.md)
 # Problem Statement and Motivation
@@ -38,16 +38,10 @@ The following ROM features are currently missing:
 Status of the various APIs and variables from the original ROMs
-## Page 0
+## Low memory locations (pages 0 - 3)
-TODO
+For the current status of the low memory location implementation andd usage check [this file](c64/aliases/,aliases_ram_lowmem.s). NOTE: available vector to certain routine does not mean that this routine is fully implemented!
 ## Pages 2 & 3
 TODO
 ## BASIC
@@ -107,7 +101,7 @@ NOTE: Even the 'DONE' routines won't support features described as missing in on
 | `$FFE7`   | `CLALL`  | DONE     |                                                    |
 | `$FFEA`   | `UDTIM`  | DONE     |                                                    |
 | `$FFED`   | `SCREEN` | DONE     |                                                    |
-| `$FFF0`   | `PLOT`   | DONE     |                                                    |
+| `$FFF0`   | `PLOT`   | PARTIAL  | cursor blink not handled                           |
 | `$FFF3`   | `IOBASE` | DONE     |                                                    |
 <br />
@@ -0,0 +1 @@
 Put KickAss.jar and KickAss.cfg into this directory.
@@ -1,63 +1,63 @@
-	;; Kernal error codes - returned in the A register
+	// Kernal error codes - returned in the A register
-	;; Described in 'Commodore 64 Programmer's Reference Guide', page 306
+	// Described in 'Commodore 64 Programmer's Reference Guide', page 306
-	.alias K_ERR_ROUTINE_TERMINATED       $00
+	.const K_ERR_ROUTINE_TERMINATED     = $00
-	.alias K_ERR_TOO_MANY_OPEN_FILES      $01
+	.const K_ERR_TOO_MANY_OPEN_FILES    = $01
-	.alias K_ERR_FILE_ALREADY_OPEN        $02
+	.const K_ERR_FILE_ALREADY_OPEN      = $02
-	.alias K_ERR_FILE_NOT_OPEN            $03
+	.const K_ERR_FILE_NOT_OPEN          = $03
-	.alias K_ERR_FILE_NOT_FOUND           $04
+	.const K_ERR_FILE_NOT_FOUND         = $04
-	.alias K_ERR_DEVICE_NOT_FOUND         $05
+	.const K_ERR_DEVICE_NOT_FOUND       = $05
-	.alias K_ERR_FILE_NOT_INPUT           $06
+	.const K_ERR_FILE_NOT_INPUT         = $06
-	.alias K_ERR_FILE_NOT_OUTPUT          $07
+	.const K_ERR_FILE_NOT_OUTPUT        = $07
-	.alias K_ERR_FILE_NAME_MISSING        $08
+	.const K_ERR_FILE_NAME_MISSING      = $08
-	.alias K_ERR_ILLEGAL_DEVICE_NUMBER    $09
+	.const K_ERR_ILLEGAL_DEVICE_NUMBER  = $09
-	.alias K_ERR_TOP_MEM_RS232            $F0
+	.const K_ERR_TOP_MEM_RS232          = $F0
-	;; Kernal status codes for READST routine (IOSTATUS)
+	// Kernal status codes for READST routine (IOSTATUS)
-	;; Described in 'Commodore 64 Programmer's Reference Guide', page 292
+	// Described in 'Commodore 64 Programmer's Reference Guide', page 292
-	;; For IEC devices
+	// For IEC devices
-	.alias K_STS_TIMEOUT_WRITE            $01
+	.const K_STS_TIMEOUT_WRITE          = $01
-	.alias K_STS_TIMEOUT_READ             $02
+	.const K_STS_TIMEOUT_READ           = $02
-	.alias K_STS_EOI                      $40
+	.const K_STS_EOI                    = $40
-	.alias K_STS_DEVICE_NOT_FOUND         $80
+	.const K_STS_DEVICE_NOT_FOUND       = $80
-	;; For tape deck
+	// For tape deck
-	.alias K_STS_SHORT_BLOCK              $04
+	.const K_STS_SHORT_BLOCK            = $04
-	.alias K_STS_LONG_BLOCK               $08
+	.const K_STS_LONG_BLOCK             = $08
-	.alias K_STS_READ_ERROR               $10
+	.const K_STS_READ_ERROR             = $10
-	.alias K_STS_CHECKSUM_ERROR           $20
+	.const K_STS_CHECKSUM_ERROR         = $20
-	.alias K_STS_END_OF_FILE              $40
+	.const K_STS_END_OF_FILE            = $40
-	.alias K_STS_END_OF_TAPE              $80
+	.const K_STS_END_OF_TAPE            = $80
-	;; BASIC error codes, taken from http://sta.c64.org/cbm64baserr.html
+	// BASIC error codes, taken from http://sta.c64.org/cbm64baserr.html
-	.alias B_ERR_TOO_MANY_FILES           $01
+	.const B_ERR_TOO_MANY_FILES         = $01
-	.alias B_ERR_FILE_OPEN                $02
+	.const B_ERR_FILE_OPEN              = $02
-	.alias B_ERR_FILE_NOT_OPEN            $03
+	.const B_ERR_FILE_NOT_OPEN          = $03
-	.alias B_ERR_FILE_NOT_FOUND           $04
+	.const B_ERR_FILE_NOT_FOUND         = $04
-	.alias B_ERR_DEVICE_NOT_PRESENT       $05
+	.const B_ERR_DEVICE_NOT_PRESENT     = $05
-	.alias B_ERR_NOT_INPUT_FILE           $06
+	.const B_ERR_NOT_INPUT_FILE         = $06
-	.alias B_ERR_NOT_OUTPUT_FILE          $07
+	.const B_ERR_NOT_OUTPUT_FILE        = $07
-	.alias B_ERR_MISSING_FILENAME         $08
+	.const B_ERR_MISSING_FILENAME       = $08
-	.alias B_ERR_ILLEGAL_DEVICE_NUMBER    $09
+	.const B_ERR_ILLEGAL_DEVICE_NUMBER  = $09
-	.alias B_ERR_NEXT_WITHOUT_FOR         $0A
+	.const B_ERR_NEXT_WITHOUT_FOR       = $0A
-	.alias B_ERR_SYNTAX                   $0B
+	.const B_ERR_SYNTAX                 = $0B
-	.alias B_ERR_RETURN_WITHOUT_GOSUB     $0C
+	.const B_ERR_RETURN_WITHOUT_GOSUB   = $0C
-	.alias B_ERR_OUT_OF_DATA              $0D
+	.const B_ERR_OUT_OF_DATA            = $0D
-	.alias B_ERR_ILLEGAL_QUANTITY         $0E
+	.const B_ERR_ILLEGAL_QUANTITY       = $0E
-	.alias B_ERR_OVERFLOW                 $0F
+	.const B_ERR_OVERFLOW               = $0F
-	.alias B_ERR_OUT_OF_MEMORY            $10
+	.const B_ERR_OUT_OF_MEMORY          = $10
-	.alias B_ERR_UNDEFD_STATEMENT         $11
+	.const B_ERR_UNDEFD_STATEMENT       = $11
-	.alias B_ERR_BAD_SUBSCRIPT            $12
+	.const B_ERR_BAD_SUBSCRIPT          = $12
-	.alias B_ERR_REDIMD_ARRAY             $13
+	.const B_ERR_REDIMD_ARRAY           = $13
-	.alias B_ERR_DIVISION_BY_ZERO         $14
+	.const B_ERR_DIVISION_BY_ZERO       = $14
-	.alias B_ERR_ILLEGAL_DIRECT           $15
+	.const B_ERR_ILLEGAL_DIRECT         = $15
-	.alias B_ERR_TYPE_MISMATCH            $16
+	.const B_ERR_TYPE_MISMATCH          = $16
-	.alias B_ERR_STRING_TOO_LONG          $17
+	.const B_ERR_STRING_TOO_LONG        = $17
-	.alias B_ERR_FILE_DATA                $18
+	.const B_ERR_FILE_DATA              = $18
-	.alias B_ERR_FORMULA_TOO_COMPLEX      $19
+	.const B_ERR_FORMULA_TOO_COMPLEX    = $19
-	.alias B_ERR_CANT_CONTINUE            $1A
+	.const B_ERR_CANT_CONTINUE          = $1A
-	.alias B_ERR_UNDEFD_FUNCTION          $1B
+	.const B_ERR_UNDEFD_FUNCTION        = $1B
-	.alias B_ERR_VERIFY                   $1C
+	.const B_ERR_VERIFY                 = $1C
-	.alias B_ERR_LOAD                     $1D
+	.const B_ERR_LOAD                   = $1D
-	.alias B_ERR_BREAK                    $1E
+	.const B_ERR_BREAK                  = $1E
@@ -1,148 +1,148 @@
-;;
+//
-;; Names of hardware registers - slightly modified names from C64 Programmer's Reference Guide
+// Names of hardware registers - slightly modified names from C64 Programmer's Reference Guide
-;;
+//
-	;; CPU memory registers
+	// CPU memory registers
-	.alias CPU_D6510      $00
+	.label CPU_D6510    = $00
-	.alias CPU_R6510      $01
+	.label CPU_R6510    = $01
-	;; VIC-II registers
+	// VIC-II registers
-	.alias VIC_SP0X       $D000
+	.label VIC_SP0X     = $D000
-	.alias VIC_SP0Y       $D001
+	.label VIC_SP0Y     = $D001
-	.alias VIC_SP1X       $D002
+	.label VIC_SP1X     = $D002
-	.alias VIC_SP1Y       $D003
+	.label VIC_SP1Y     = $D003
-	.alias VIC_SP2X       $D004
+	.label VIC_SP2X     = $D004
-	.alias VIC_SP2Y       $D005
+	.label VIC_SP2Y     = $D005
-	.alias VIC_SP3X       $D006
+	.label VIC_SP3X     = $D006
-	.alias VIC_SP3Y       $D007
+	.label VIC_SP3Y     = $D007
-	.alias VIC_SP4X       $D008
+	.label VIC_SP4X     = $D008
-	.alias VIC_SP4Y       $D009
+	.label VIC_SP4Y     = $D009
-	.alias VIC_SP5X       $D00A
+	.label VIC_SP5X     = $D00A
-	.alias VIC_SP5Y       $D00B
+	.label VIC_SP5Y     = $D00B
-	.alias VIC_SP6X       $D00C
+	.label VIC_SP6X     = $D00C
-	.alias VIC_SP6Y       $D00D
+	.label VIC_SP6Y     = $D00D
-	.alias VIC_SP7X       $D00E
+	.label VIC_SP7X     = $D00E
-	.alias VIC_SP7Y       $D00F
+	.label VIC_SP7Y     = $D00F
-	.alias VIC_MSIGX      $D010
+	.label VIC_MSIGX    = $D010
-	.alias VIC_SCROLY     $D011
+	.label VIC_SCROLY   = $D011
-	.alias VIC_RASTER     $D012
+	.label VIC_RASTER   = $D012
-	.alias VIC_LPENX      $D013
+	.label VIC_LPENX    = $D013
-	.alias VIC_LPENY      $D014
+	.label VIC_LPENY    = $D014
-	.alias VIC_SPENA      $D015
+	.label VIC_SPENA    = $D015
-	.alias VIC_SCROLX     $D016
+	.label VIC_SCROLX   = $D016
-	.alias VIC_YXPAND     $D017
+	.label VIC_YXPAND   = $D017
-	.alias VIC_YMCSB      $D018
+	.label VIC_YMCSB    = $D018
-	.alias VIC_IRQ        $D019
+	.label VIC_IRQ      = $D019
-	.alias VIC_IRQMSK     $D01A
+	.label VIC_IRQMSK   = $D01A
-	.alias VIC_SPBGPR     $D01B
+	.label VIC_SPBGPR   = $D01B
-	.alias VIC_SPMC       $D01C
+	.label VIC_SPMC     = $D01C
-	.alias VIC_XXPAND     $D01D
+	.label VIC_XXPAND   = $D01D
-	.alias VIC_SPSPCL     $D01E
+	.label VIC_SPSPCL   = $D01E
-	.alias VIC_SPBGCL     $D01F
+	.label VIC_SPBGCL   = $D01F
-	.alias VIC_EXTCOL     $D020
+	.label VIC_EXTCOL   = $D020
-	.alias VIC_BGCOL0     $D021
+	.label VIC_BGCOL0   = $D021
-	.alias VIC_BGCOL1     $D022
+	.label VIC_BGCOL1   = $D022
-	.alias VIC_BGCOL2     $D023
+	.label VIC_BGCOL2   = $D023
-	.alias VIC_BGCOL3     $D024
+	.label VIC_BGCOL3   = $D024
-	.alias VIC_SPMC0      $D025
+	.label VIC_SPMC0    = $D025
-	.alias VIC_SPMC1      $D026
+	.label VIC_SPMC1    = $D026
-	.alias VIC_SP0COL     $D027
+	.label VIC_SP0COL   = $D027
-	.alias VIC_SP1COL     $D028
+	.label VIC_SP1COL   = $D028
-	.alias VIC_SP2COL     $D029
+	.label VIC_SP2COL   = $D029
-	.alias VIC_SP3COL     $D02A
+	.label VIC_SP3COL   = $D02A
-	.alias VIC_SP4COL     $D02B
+	.label VIC_SP4COL   = $D02B
-	.alias VIC_SP5COL     $D02C
+	.label VIC_SP5COL   = $D02C
-	.alias VIC_SP6COL     $D02D
+	.label VIC_SP6COL   = $D02D
-	.alias VIC_SP7COL     $D02E
+	.label VIC_SP7COL   = $D02E
-	;; SID registers
+	// SID registers
-	.alias SID_FRELO1    $D400
+	.label SID_FRELO1   = $D400
-	.alias SID_FREHI1    $D401
+	.label SID_FREHI1   = $D401
-	.alias SID_PWLO1     $D402
+	.label SID_PWLO1    = $D402
-	.alias SID_PWHI1     $D403
+	.label SID_PWHI1    = $D403
-	.alias SID_VCREG1    $D404
+	.label SID_VCREG1   = $D404
-	.alias SID_ATDCY1    $D405
+	.label SID_ATDCY1   = $D405
-	.alias SID_SUREL1    $D406
+	.label SID_SUREL1   = $D406
-	.alias SID_FRELO2    $D407
+	.label SID_FRELO2   = $D407
-	.alias SID_FREHI2    $D408
+	.label SID_FREHI2   = $D408
-	.alias SID_PWLO2     $D409
+	.label SID_PWLO2    = $D409
-	.alias SID_PWHI2     $D40A
+	.label SID_PWHI2    = $D40A
-	.alias SID_VCREG2    $D40B
+	.label SID_VCREG2   = $D40B
-	.alias SID_ATDCY2    $D40C
+	.label SID_ATDCY2   = $D40C
-	.alias SID_SUREL2    $D40D
+	.label SID_SUREL2   = $D40D
-	.alias SID_FRELO3    $D40E
+	.label SID_FRELO3   = $D40E
-	.alias SID_FREHI3    $D40F
+	.label SID_FREHI3   = $D40F
-	.alias SID_PWLO3     $D410
+	.label SID_PWLO3    = $D410
-	.alias SID_PWHI3     $D411
+	.label SID_PWHI3    = $D411
-	.alias SID_VCREG3    $D412
+	.label SID_VCREG3   = $D412
-	.alias SID_ATDCY3    $D413
+	.label SID_ATDCY3   = $D413
-	.alias SID_SUREL3    $D414
+	.label SID_SUREL3   = $D414
-	.alias SID_CUTLO     $D415
+	.label SID_CUTLO    = $D415
-	.alias SID_CUTHI     $D416
+	.label SID_CUTHI    = $D416
-	.alias SID_RESON     $D417
+	.label SID_RESON    = $D417
-	.alias SID_SIGVOL    $D418
+	.label SID_SIGVOL   = $D418
-	.alias SID_POTX      $D419
+	.label SID_POTX     = $D419
-	.alias SID_POTY      $D41A
+	.label SID_POTY     = $D41A
-	.alias SID_RANDOM    $D41B
+	.label SID_RANDOM   = $D41B
-	.alias SID_ENV3      $D41C
+	.label SID_ENV3     = $D41C
-	;; CIA #1 registers
+	// CIA #1 registers
-	.alias CIA1_PRA       $DC00
+	.label CIA1_PRA     = $DC00
-	.alias CIA1_PRB       $DC01
+	.label CIA1_PRB     = $DC01
-	.alias CIA1_DDRA      $DC02
+	.label CIA1_DDRA    = $DC02
-	.alias CIA1_DDRB      $DC03
+	.label CIA1_DDRB    = $DC03
-	.alias CIA1_TIMALO    $DC04
+	.label CIA1_TIMALO  = $DC04
-	.alias CIA1_TIMAHI    $DC05
+	.label CIA1_TIMAHI  = $DC05
-	.alias CIA1_TIMBLO    $DC06
+	.label CIA1_TIMBLO  = $DC06
-	.alias CIA1_TIMBHI    $DC07
+	.label CIA1_TIMBHI  = $DC07
-	.alias CIA1_TODTEN    $DC08
+	.label CIA1_TODTEN  = $DC08
-	.alias CIA1_TODSEC    $DC09
+	.label CIA1_TODSEC  = $DC09
-	.alias CIA1_TODMIN    $DC0A
+	.label CIA1_TODMIN  = $DC0A
-	.alias CIA1_TODHRS    $DC0B
+	.label CIA1_TODHRS  = $DC0B
-	.alias CIA1_SDR       $DC0C
+	.label CIA1_SDR     = $DC0C
-	.alias CIA1_ICR       $DC0D
+	.label CIA1_ICR     = $DC0D
-	.alias CIA1_CRA       $DC0E
+	.label CIA1_CRA     = $DC0E
-	.alias CIA1_CRB       $DC0F
+	.label CIA1_CRB     = $DC0F
-	;; CIA #2 registers
+	// CIA #2 registers
-	.alias CIA2_PRA       $DD00 ; VIC bank switching and IEC port
+	.label CIA2_PRA     = $DD00  // VIC bank switching and IEC port
-	.alias CIA2_PRB       $DD01
+	.label CIA2_PRB     = $DD01
-	.alias CIA2_DDRA      $DD02
+	.label CIA2_DDRA    = $DD02
-	.alias CIA2_DDRB      $DD03
+	.label CIA2_DDRB    = $DD03
-	.alias CIA2_TIMALO    $DD04
+	.label CIA2_TIMALO  = $DD04
-	.alias CIA2_TIMAHI    $DD05
+	.label CIA2_TIMAHI  = $DD05
-	.alias CIA2_TIMBLO    $DD06
+	.label CIA2_TIMBLO  = $DD06
-	.alias CIA2_TIMBHI    $DD07
+	.label CIA2_TIMBHI  = $DD07
-	.alias CIA2_TODTEN    $DD08
+	.label CIA2_TODTEN  = $DD08
-	.alias CIA2_TODSEC    $DD09
+	.label CIA2_TODSEC  = $DD09
-	.alias CIA2_TODMIN    $DD0A
+	.label CIA2_TODMIN  = $DD0A
-	.alias CIA2_TODHRS    $DD0B
+	.label CIA2_TODHRS  = $DD0B
-	.alias CIA2_SDR       $DD0C
+	.label CIA2_SDR     = $DD0C
-	.alias CIA2_ICR       $DD0D
+	.label CIA2_ICR     = $DD0D
-	.alias CIA2_CRA       $DD0E
+	.label CIA2_CRA     = $DD0E
-	.alias CIA2_CRB       $DD0F
+	.label CIA2_CRB     = $DD0F
-	;; CIA #2 helper bits - IEC bus
+	// CIA #2 helper bits - IEC bus
-	.alias BIT_CIA2_PRA_ATN_OUT $08    ; 1 - low (pulled), 0 - high (released)
+	.const BIT_CIA2_PRA_ATN_OUT  = $08  // 1 - low (pulled), 0 - high (released)
-	.alias BIT_CIA2_PRA_CLK_OUT $10    ; 1 - low (pulled), 0 - high (released)
+	.const BIT_CIA2_PRA_CLK_OUT  = $10  // 1 - low (pulled), 0 - high (released)
-	.alias BIT_CIA2_PRA_DAT_OUT $20    ; 1 - low (pulled), 0 - high (released)
+	.const BIT_CIA2_PRA_DAT_OUT  = $20  // 1 - low (pulled), 0 - high (released)
-	.alias BIT_CIA2_PRA_CLK_IN  $40    ; 0 - low (pulled), 1 - high (released)
+	.const BIT_CIA2_PRA_CLK_IN   = $40  // 0 - low (pulled), 1 - high (released)
-	.alias BIT_CIA2_PRA_DAT_IN  $80    ; 0 - low (pulled), 1 - high (released)
+	.const BIT_CIA2_PRA_DAT_IN   = $80  // 0 - low (pulled), 1 - high (released)
@@ -1,98 +1,236 @@
-;;
+//
-;; Names of ZP and low memory locations
+// Names of ZP and low memory locations:
-;; (https://www.c64-wiki.com/wiki/Zeropage)
+// - Compute's Mapping the Commodore 64
-;;
+// - https://www.c64-wiki.com/wiki/Zeropage
 // - http://unusedino.de/ec64/technical/project64/memory_maps.html
 //
-	;; $00-$01 - 6502 CPU registers are here
+	// $00-$01 - 6502 CPU registers are here
-    ;;
+	//
-	;; Page 0 - BASIC area ($02-$8F)
+	// Page 0 - BASIC area ($02-$8F)
-    ;;
+	//
-	.alias TXTTAB     $2B
+	//                 $02             -- UNUSED --          free for user software
 	.label ADRAY1    = $03 // $03-$04  -- NOT IMPLEMENTED --
 	.label ADRAY2    = $05 // $05-$06  -- NOT IMPLEMENTED --
 	.label CHARAC    = $07 //          [!] our implementation might be different  XXX give more details
 	.label ENDCHR    = $08 //          [!] our implementation might be different  XXX give more details
 	.label TRMPOS    = $09 //          -- NOT IMPLEMENTED --
 	.label VERCKB    = $0A //          -- NOT IMPLEMENTED --
 	.label COUNT     = $0B //          [!] our implementation might be different  XXX give more details
 	.label DIMFLG    = $0C //          [!] our implementation might be different  XXX give more details
 	.label VALTYP    = $0D //          -- NOT IMPLEMENTED --
 	.label INTFLG    = $0E //          -- NOT IMPLEMENTED --
 	.label GARBFL    = $0F //          [!] our implementation might be different  XXX give more details
 	.label SUBFLG    = $10 //          -- NOT IMPLEMENTED --
 	.label INPFLG    = $11 //          -- NOT IMPLEMENTED --
 	.label TANSGN    = $12 //          -- NOT IMPLEMENTED --
 	.label CHANNL    = $13 //          -- NOT IMPLEMENTED --
 	.label LINNUM    = $14 // $14-$15  BASIC line number, [!] also used by DOS Wedge
 	.label TEMPPT    = $16 //          -- NOT IMPLEMENTED --
 	.label LASTPT    = $17 // $17-$18  -- NOT IMPLEMENTED --
 	.label TEMPST    = $19 // $19-$21  -- NOT IMPLEMENTED --
 	.label INDEX     = $22 // $22-$25  -- NOT IMPLEMENTED -- temporary variables
 	.label RESHO     = $26 // $26-$2A  -- NOT IMPLEMENTED --
 	.label TXTTAB    = $2B // $2B-$2C  start of BASIC code
 	.label VARTAB    = $2D // $2D-$2E  end of BASIC code, start of variables
 	.label ARYTAB    = $2F // $2F-$30  -- NOT IMPLEMENTED --
 	.label STREND    = $31 // $31-$32  -- NOT IMPLEMENTED --
 	.label FRETOP    = $33 // $33-$34  -- NOT IMPLEMENTED --
 	.label FRESPC    = $35 // $35-$36  [!] our implementation might be different  XXX give more details
 	// .label MEMSIZ    = $37 // $37-$38  -- NOT IMPLEMENTED -- highest address of BASIC memory XXX remove name conflict
 	.label CURLIN    = $39 // $39-$3A  current BASIC line number
 	.label OLDLIN    = $3B // $3B-$3C  previous BASIC line number
 	.label OLDTXT    = $3D // $3D-$3E  current BASIC line pointer
 	.label DATLIN    = $3F // $3F-$40  -- NOT IMPLEMENTED --
 	.label DATPTR    = $41 // $41-$42  -- NOT IMPLEMENTED --
 	.label INPPTR    = $43 // $43-$44  -- NOT IMPLEMENTED --
 	.label VARNAM    = $45 // $45-$46  -- NOT IMPLEMENTED --
 	.label VARPNT    = $47 // $47-$48  -- NOT IMPLEMENTED --
 	.label FORPNT    = $49 // $49-$4A  -- NOT IMPLEMENTED --
 	.label OPPTR     = $4B // $4B-$4C  -- NOT IMPLEMENTED --
 	.label OPMASK    = $4D //          -- NOT IMPLEMENTED --
 	.label DEFPNT    = $4E // $4E-$4F  -- NOT IMPLEMENTED --
 	.label DSCPNT    = $50 // $50-$52  -- NOT IMPLEMENTED --
 	.label FOUR6     = $53 //          -- NOT IMPLEMENTED --
 	.label JMPER     = $54 // $54-$56  -- NOT IMPLEMENTED --
 	.label TEMPF1    = $57 // $57-$5B  BASIC numeric work area
 	.label TEMPF2    = $5C // $5C-$60  BASIC numeric work area
 	.label FAC1      = $61 // $61-$66  -- NOT IMPLEMENTED --
 	.label SGNFLG    = $67 //          -- NOT IMPLEMENTED --
 	.label BITS      = $68 //          -- NOT IMPLEMENTED --
 	.label FAC2      = $69 // $69-$6E  -- NOT IMPLEMENTED -- [!] also used for memory move pointers
 	.label ARISGN    = $6F //          -- NOT IMPLEMENTED --
 	.label FACOV     = $70 //          -- NOT IMPLEMENTED --
 	.label FBUFPT    = $67 // $71-$72  -- NOT IMPLEMENTED --
 	.label CHRGET    = $73 // $73-$8A  -- NOT IMPLEMENTED --
 	.label TXTPTR    = $7A // $7A-$7B  current BASIC statement pointer
 	.label RNDX      = $8B // $8B-$8F  -- NOT IMPLEMENTED --
-    ;;
+	//
-	;; Page 0 - Kernal area ($90-$FF)
+	// Page 0 - Kernal area ($90-$FF)
-    ;;
+	//
-	.alias IOSTATUS   $90
+	.label IOSTATUS  = $90
-	.alias STKEY      $91 ; Keys down clears bits. STOP - bit 7, C= - bit 6, SPACE - bit 4, CTRL - bit 2
+	.label STKEY     = $91  //          Keys down clears bits. STOP - bit 7, C= - bit 6, SPACE - bit 4, CTRL - bit 2
 	.label SVXT      = $92  //          -- NOT IMPLEMENTED --
 	.label VERCK     = $93  //          0 = LOAD, 1 = VERIFY    XXX rename to VERCKK
 	.label C3PO      = $94  //          flag - is BSOUR content valid
 	.label BSOUR     = $95  //          serial bus buffered output byte
 	.label SYNO      = $96  //          -- NOT IMPLEMENTED --
 	.label XSAV      = $97  //          -- NOT IMPLEMENTED --
 	.label LDTND     = $98  //          number of entries in LAT / FAT / SAT tables
 	.label DFLTN     = $99  //          default input device
 	.label DFLTO     = $9A  //          default output device
 	.label PRTY      = $9B  //          -- NOT IMPLEMENTED --
 	.label DPSW      = $9C  //          -- NOT IMPLEMENTED --
 	.label MSGFLG    = $9D  //          bit 6 = error messages, bit 7 = control message
 	.label PTR1      = $9E  //          -- NOT IMPLEMENTED --
 	.label PTR2      = $9F  //          -- NOT IMPLEMENTED --
 	.label TIME      = $A0  // $A0-$A2, jiffy clock
 	.label IEC_TMP1  = $A3  //          temporary variable for tape and IEC, [!] our usage probably differs in details   XXX rename to TSFCNT
 	.label IEC_TMP2  = $A4  //          temporary variable for tape and IEC, [!] our usage probably differs in details   XXX rename to TBTCNT
 	.label CNTDN     = $A5  //          -- NOT IMPLEMENTED --
 	.label BUFPNT    = $A6  //          -- NOT IMPLEMENTED --
 	.label INBIT     = $A7  //          -- NOT IMPLEMENTED --
 	.label BITCI     = $A8  //          -- NOT IMPLEMENTED --
 	.label RINONE    = $A9  //          -- NOT IMPLEMENTED --
 	.label RIDDATA   = $AA  //          -- NOT IMPLEMENTED --
 	.label RIPRTY    = $AB  //          -- NOT IMPLEMENTED --
 	.label SAL       = $AC  // $AC-$AD  -- NOT IMPLEMENTED -- (implemented screen part)
 	.label EAL       = $AE  // $AE-$AF  -- NOT IMPLEMENTED -- [!] used also byy screen editor
 	.label CMP0      = $B0  // $B0-$B1, temporary tape storage, [!] here used for BRK instruction address
 	.label TAPE1     = $B2  // $B2-$B3  tape buffer pointer
 	.label BITTS     = $B4  //          -- NOT IMPLEMENTED --
 	.label NXTBIT    = $B5  //          -- NOT IMPLEMENTED --
 	.label RODATA    = $B6  //          -- NOT IMPLEMENTED --
 	.label FNLEN     = $B7  //          current file name length
 	.label LA        = $B8  //          current logical_file number
 	.label SA        = $B9  //          current secondary address
 	.label FA        = $BA  //          current device number
 	.label FNADDR    = $BB  // $BB-$BC, current file name pointer
 	.label ROPRTY    = $BD  //          -- NOT IMPLEMENTED --
 	.label FSBLK     = $BE  //          -- NOT IMPLEMENTED --
 	.label MYCH      = $BF  //          -- NOT IMPLEMENTED --
 	.label CAS1      = $C0  //          -- NOT IMPLEMENTED --
 	.label STAL      = $C1  // $C1-$C2, LOAD/SAVE start address
 	.label MEMUS     = $C3  // $C3-$C4, temporary address for tape LOAD/SAVE    XXX rename to MEMUSS
 	.label LSTX      = $C5  //          last keyy matrix position [!] our usage probably differs in details
 	.label NDX       = $C6  //          number of chars in keyboard buffer
 	.label RVS       = $C7  //          flag, whether to print reversed characters
 	.label INDX      = $C8  //          end of logical line (column, 0-79)
 	.label LXSP      = $C9  // $C9-$CA  start of input, X/Y position
 	.label SFDX      = $CB  //          -- NOT IMPLEMENTED --
 	.label BLNSW     = $CC  //          cursor blink disable flag
 	.label BLNCT     = $CD  //          cursor blink countdown
 	.label GDBLN     = $CE  //          cursorb saved character
 	.label BLNON     = $CF  //          cursor visibilityy flag
 	.label CRSW      = $D0  //          whether to input from screen or keyboard
 	.label PNT       = $D1  // $D1-$D2  pointer to the current screen line
 	.label PNTR      = $D3  //          current screen X position
 	.label QTSW      = $D4  //          quote mode flag
 	.label LNMX      = $D5  //          logical line length, [!] our usage probably differs in details
 	.label TBLX      = $D6  //          current screen Y position
 	.label SCHAR     = $D7  //          ASCII value of the last printed character
 	.label INSRT     = $D8  //          insert mode flag/counter
 	.label LDTB1     = $D9  // $D9-$F2  screen line link table, [!] our usage is different  XXX give more details
 	.label USER      = $F3  // $F3-$F4  pointer to current color RAM location
 	.label KEYTAB    = $F5  // $F5-$F6  -- NOT IMPLEMENTED --
 	.label RIBUF     = $F7  // $F7-$F8  -- NOT IMPLEMENTED --
 	.label ROBUF     = $F9  // $F9-$FA  -- NOT IMPLEMENTED --
 	//                 $FB     $FB-$FE  -- UNUSED --          free for user software
 	.label BASZPT    = $FF  //          -- NOT IMPLEMENTED --
-	.alias VERCK      $93 ; 0 = LOAD, 1 = VERIVY
+	//
 	// Page 1
 	//
-	.alias C3PO       $94 ; flag - is BSOUR content valid
+	.label STACK     = $100  // $100-$1FF, processor stack
 	.alias BSOUR      $95 ; serial bus buffered output byte
-	.alias LDTND      $98 ; number of entries in LAT / FAT / SAT tables
+	//
-	.alias DFLTN      $99
+	// Pages 2 & 3
-	.alias DFLTO      $9A
+	//
-	.alias MSGFLG     $9D ; bit 6 = error messages, bit 7 = control message
+	.label BUF       = $200  // $200-$250, BASIC line editor input buffer (81 bytes)
 	// [!] XXX document $251-$258 usage
 	.label LAT       = $259  // $259-$262, logical file numbers (table, 10 bytes)
 	.label FAT       = $263  // $263-$26C, device numbers       (table, 10 bytes)
 	.label SAT       = $26D  // $26D-$276, secondary addresses  (table, 10 bytes)
 	.label KEYD      = $277  // $277-$280  keyboard buffer
 	.label MEMSTR    = $281  // $281-$282  XXX rename to LORAM
 	.label MEMSIZ    = $283  // $283-$284, NOTE: Mapping the 64 erroneously has the hex as $282, while the DEC is correct XXX rename to HIRAM
 	.label TIMOUT    = $285  //            IEEE-488 timeout
 	.label COLOR     = $286  //            current text foreground color
 	.label GDCOL     = $287  //            color of character under cursor
 	.label HIBASE    = $288  //            high byte of start of screen
 	.label XMAX      = $289  //            max keyboard buffer size
 	.label RPTFLG    = $28A  //            -- NOT IMPLEMENTED --
 	.label KOUNT     = $28B  //            -- NOT IMPLEMENTED --
 	.label DELAY     = $28C  //            -- NOT IMPLEMENTED --
 	.label SHFLAG    = $28D  //            bucky keys (SHIFT/CTRL/C=) flags
 	.label LSTSHF    = $28E  //            last bucky key flags
 	.label KEYLOG    = $28F  // $28F-$290  -- NOT IMPLEMENTED --
 	.label MODE      = $291  //            flag, is case switch allowed
 	.label AUTODN    = $292  //            -- NOT IMPLEMENTED --
 	.label M51CRT    = $293  //            -- NOT IMPLEMENTED -- mock 6551
 	.label M51CDR    = $294  //            -- NOT IMPLEMENTED -- mock 6551
 	.label M51AJB    = $295  // $295-$296  -- NOT IMPLEMENTED -- mock 6551
 	.label RSSTAT    = $297  //            -- NOT IMPLEMENTED -- mock 6551, RS-232 status
 	.label BITNUM    = $298  //            -- NOT IMPLEMENTED --
 	.label BAUDOF    = $299  // $299-$29A  -- NOT IMPLEMENTED --
 	.label RIDBE     = $29B  //            -- NOT IMPLEMENTED --
 	.label RIDBS     = $29C  //            -- NOT IMPLEMENTED --
 	.label RODBS     = $29D  //            -- NOT IMPLEMENTED --
 	.label RODBE     = $29E  //            -- NOT IMPLEMENTED --
 	.label IRQTMP    = $29F  // $29F-$2A0  -- NOT IMPLEMENTED --
 	.label ENABL     = $2A1  //            -- NOT IMPLEMENTED --
 	.label TODSNS    = $2A2  //            -- NOT IMPLEMENTED --
 	.label TRDTMP    = $2A3  //            -- NOT IMPLEMENTED --
 	.label TD1IRQ    = $2A4  //            -- NOT IMPLEMENTED --
 	.label TLNIDX    = $2A5  //            -- NOT IMPLEMENTED --
 	.label PALNTSC   = $2A6  //            0 = NTSC, 1 = PAL   XXX rename to TVSFLG
 	// [!] XXX document $2A7-$2FF usage
-	.alias TIME       $A0 ; $A0-$A2, jiffy clock
+	// BASIC vectors
 	.label IERROR    = $300  // $300-$301  -- NOT IMPLEMENTED --
 	.label IMAIN     = $302  // $302-$303  -- NOT IMPLEMENTED --
 	.label ICRNCH    = $304  // $304-$305  -- NOT IMPLEMENTED --
 	.label IQPLOP    = $306  // $306-$307  -- NOT IMPLEMENTED --
 	.label IGONE     = $308  // $308-$309  -- NOT IMPLEMENTED --
 	.label IEVAL     = $30A  // $30A-$30B  -- NOT IMPLEMENTED --
-	.alias IEC_TMP1   $A3 ; temporary variable for tape and IEC
+	.label SAREG     = $30C  //            .A storage, for SYS call
-	.alias IEC_TMP2   $A4 ; temporary variable for tape and IEC
+	.label SXREG     = $30D  //            .X storage, for SYS call
 	.label SYREG     = $30E  //            .Y storage, for SYS call
 	.label SPREG     = $30F  //            .P storage, for SYS call
-	.alias CMP0       $B0 ; $B0-$B1, temporary tape storage, we use it too for BRK instruction address
+	.label USRPOK    = $310  //            -- NOT IMPLEMENTED -- JMP instruction
 	.label USRADD    = $311  // $311-$312  -- NOT IMPLEMENTED --
 	//                 $313                -- UNUSED --          free for user software
-	.alias FNLEN      $B7 ; current file name length
+	// Kernal vectors - interrupts
 	.label CINV      = $314  // $314-$315
 	.label CBINV     = $316  // $316-$317
 	.label NMINV     = $318  // $318-$319
-	.alias FNADDR     $BB ; $BB-$BC, current file name pointer
+	// Kernal vectors - routines
 	.label IOPEN     = $31A  // $31A-$31B
 	.label ICLOSE    = $31C  // $31C-$31D
 	.label ICHKIN    = $31E  // $31E-$31F
 	.label ICKOUT    = $320  // $320-$321
 	.label ICLRCH    = $322  // $322-$323
 	.label IBASIN    = $324  // $324-$325
 	.label IBSOUT    = $326  // $326-$327
 	.label ISTOP     = $328  // $328-$329
 	.label IGETIN    = $32A  // $32A-$32B
 	.label ICLALL    = $32C  // $32C-$32D
 	.label USRCMD    = $32E  // $32E-$32F
 	.label ILOAD     = $330  // $330-$331
 	.label ISAVE     = $332  // $332-$333
-	.alias STAL       $C1 ; $C1-$C2 LOAD/SAVE start address
+	//                 $314     $334-$33B  -- UNUSED --          free for user software
 	.alias MEMUS      $C3 ; $C3-$C4 temporary address for tape LOAD/SAVE
-	;;
+	.label TBUFFR    = $33C  // $33C-$3FB, -- NOT IMPLEMENTED --, tape buffer
 	;; Other low memory addresses
 	;;
-	.alias BUF        $200 ; $200-$250 (81 bytes), BASIC line editor input buffer
+	//                 $3FC     $3FC-$3FF  -- UNUSED --          free for user software
 	;; Kernal tables for opened files, 10 entries each
 	.alias LAT        $259 ; logical file numbers
 	.alias FAT        $263 ; device numbers
 	.alias SAT        $26D ; secondary addresses
 	.alias MEMSTR     $281
 	.alias MEMSIZ     $283 ; NOTE: Mapping the 64 erroniously has the hex as $282, while the DEC is correct
 	.alias TIMOUT     $285 ; IEEE-488 timeout
 	.alias HIBASE     $288 ; high byte of start of screen
 	.alias RSSTAT     $297 ; RS-232 status
 	.alias PALNTSC    $2A6 ; 0 = NTSC, 1 = PAL
 	;; Registers for SYS call
 	.alias SAREG      $30C
 	.alias SXREG      $30D
 	.alias SYREG      $30E
 	.alias SPREG      $30F
 	.alias USRPOK     $310 ; JMP instruction
 	.alias USRADD     $311 ; $311 - $312
 	;; Kernal vectors - interrupts
 	.alias CINV       $314
 	.alias CBINV      $316 
 	.alias NMINV      $318
 	;; Kernal vectors - routines
 	.alias IOPEN      $31A
 	.alias ICLOSE     $31C
 	.alias ICHKIN     $31E
 	.alias ICKOUT     $320
 	.alias ICLRCH     $322
 	.alias IBASIN     $324
 	.alias IBSOUT     $326
 	.alias ISTOP      $328
 	.alias IGETIN     $32A
 	.alias ICLALL     $32C
 	.alias USRCMD     $32E
 	.alias ILOAD      $330
 	.alias ISAVE      $331
 	.alias TBUFFR     $33C ; $33C-$3FB, tape buffer	
@@ -1,5 +1,4 @@
-	;; BASIC startup vector
+	// BASIC startup vectors
-	
+	.label IBASIC_COLD_START  = $A000
-	.alias IBASIC_COLD_START     $A000
+	.label IBASIC_WARM_START  = $A002
 	.alias IBASIC_WARM_START     $A002
@@ -1,5 +1,5 @@
-	;; Cartridge ROM locations
+	// Cartridge ROM locations
-	.alias ICART_COLD_START    $8000 ; $8000-$8001, cartridge cold start vector
+	.label ICART_COLD_START  = $8000  // $8000-$8001, cartridge cold start vector
-	.alias ICART_WARM_START    $8002 ; $8002-$8003, cartridge warm start vector (RESTORE key)
+	.label ICART_WARM_START  = $8002  // $8002-$8003, cartridge warm start vector (RESTORE key)
-	.alias CART_SIG            $8004 ; 5 bytes, signature for cartridge detection
+	.label CART_SIG          = $8004  // $8004-$8008, signature for cartridge detection
@@ -1,41 +1,41 @@
-	;; Kernal jump table
+	// Kernal jump table
-	.alias JCINT     $FF81
+	.label JCINT    = $FF81
-	.alias JIOINIT   $FF84
+	.label JIOINIT  = $FF84
-	.alias JRAMTAS   $FF87
+	.label JRAMTAS  = $FF87
-	.alias JRESTOR   $FF8A
+	.label JRESTOR  = $FF8A
-	.alias JVECTOR   $FF8D
+	.label JVECTOR  = $FF8D
-	.alias JSETMSG   $FF90
+	.label JSETMSG  = $FF90
-	.alias JSECOND   $FF93
+	.label JSECOND  = $FF93
-	.alias JTKSA     $FF96
+	.label JTKSA    = $FF96
-	.alias JMEMTOP   $FF99
+	.label JMEMTOP  = $FF99
-	.alias JMEMBOT   $FF9C
+	.label JMEMBOT  = $FF9C
-	.alias JSCNKEY   $FF9F
+	.label JSCNKEY  = $FF9F
-	.alias JSETTMO   $FFA2
+	.label JSETTMO  = $FFA2
-	.alias JACPTR    $FFA5
+	.label JACPTR   = $FFA5
-	.alias JCIOUT    $FFA8
+	.label JCIOUT   = $FFA8
-	.alias JUNTLK    $FFAB
+	.label JUNTLK   = $FFAB
-	.alias JUNLSN    $FFAE
+	.label JUNLSN   = $FFAE
-	.alias JLISTEN   $FFB1
+	.label JLISTEN  = $FFB1
-	.alias JTALK     $FFB4
+	.label JTALK    = $FFB4
-	.alias JREADST   $FFB7
+	.label JREADST  = $FFB7
-	.alias JSETFLS   $FFBA
+	.label JSETFLS  = $FFBA
-	.alias JSETNAM   $FFBD
+	.label JSETNAM  = $FFBD
-	.alias JOPEN     $FFC0
+	.label JOPEN    = $FFC0
-	.alias JCLOSE    $FFC3
+	.label JCLOSE   = $FFC3
-	.alias JCHKIN    $FFC6
+	.label JCHKIN   = $FFC6
-	.alias JCKOUT    $FFC9
+	.label JCKOUT   = $FFC9
-	.alias JCLRCHN   $FFCC
+	.label JCLRCHN  = $FFCC
-	.alias JCHRIN    $FFCF
+	.label JCHRIN   = $FFCF
-	.alias JCHROUT   $FFD2
+	.label JCHROUT  = $FFD2
-	.alias JLOAD     $FFD5
+	.label JLOAD    = $FFD5
-	.alias JSAVE     $FFD8
+	.label JSAVE    = $FFD8
-	.alias JSETTIM   $FFDB
+	.label JSETTIM  = $FFDB
-	.alias JRDTIM    $FFDE
+	.label JRDTIM   = $FFDE
-	.alias JSTOP     $FFE1
+	.label JSTOP    = $FFE1
-	.alias JGETIN    $FFE4
+	.label JGETIN   = $FFE4
-	.alias JCLALL    $FFE7
+	.label JCLALL   = $FFE7
-	.alias JUDTIM    $FFEA
+	.label JUDTIM   = $FFEA
-	.alias JSCREEN   $FFED
+	.label JSCREEN  = $FFED
-	.alias JPLOT     $FFF0
+	.label JPLOT    = $FFF0
-	.alias JIOBASE   $FFF3
+	.label JIOBASE  = $FFF3
@@ -1,126 +1,128 @@
-;	Names of ZP and low memory locations
+// Names of ZP and low memory locations
-;	(Only those for now that we feel the need to implement initially)
+// (Only those for now that we feel the need to implement initially)
-;	(https://www.c64-wiki.com/wiki/Zeropage)
+// (https://www.c64-wiki.com/wiki/Zeropage)
-	.alias tokenise_work1 $7
+// XXX get rid of this file, use ,aliases_ram_lowmem.s instead
 	.alias tokenise_work2 $8
 	.alias tokenise_work3 $B
 	.alias tokenise_work4 $F
 	.alias basic_line_number $14
 	.alias temp_string_ptr $35
 	.alias load_or_verify_or_tokenise_work5 $C
 	.alias basic_work22 $22
 	.alias basic_work23 $23
 	.alias basic_work24 $24
 	.alias basic_work25 $25
-	;; The various pointers that separate memory regions for BASIC storage
+	.label tokenise_work1 = $7
-	;; We have multiple names for the ones that mark the boundary of regions.
+	.label tokenise_work2 = $8
-	.alias basic_start_of_text_ptr $2b
+	.label tokenise_work3 = $B
-	.alias basic_end_of_text_ptr $2d
+	.label tokenise_work4 = $F
-	.alias basic_start_of_vars_ptr $2d
+	.label basic_line_number = $14
-	.alias basic_end_of_vars_ptr $2f
+	.label temp_string_ptr = $35
-	.alias basic_start_of_arrays_ptr $2f
+	.label load_or_verify_or_tokenise_work5 = $C
-	.alias basic_end_of_arrays_ptr $31
+	.label basic_work22 = $22
-	.alias basic_start_of_free_space_ptr $31
+	.label basic_work23 = $23
-	.alias basic_start_of_strings_ptr $33
+	.label basic_work24 = $24
-	.alias basic_top_of_memory_ptr $37
+	.label basic_work25 = $25
 	.alias basic_current_line_number $39
 	.alias basic_previous_line_number $3b
 	.alias basic_current_line_ptr $3d
-	;; Note that the statement point is in the CHRGET/CHRGOT routine
+	// The various pointers that separate memory regions for BASIC storage
-	;; in ZP RAM.  (Compute's Mapping the 64, p25)
+	// We have multiple names for the ones that mark the boundary of regions.
-	.alias basic_current_statement_ptr $7a
+	.label basic_start_of_text_ptr = $2b
 	.label basic_end_of_text_ptr = $2d
 	.label basic_start_of_vars_ptr = $2d
 	.label basic_end_of_vars_ptr = $2f
 	.label basic_start_of_arrays_ptr = $2f
 	.label basic_end_of_arrays_ptr = $31
 	.label basic_start_of_free_space_ptr = $31
 	.label basic_start_of_strings_ptr = $33
 	.label basic_top_of_memory_ptr = $37
 	.label basic_current_line_number = $39
 	.label basic_previous_line_number = $3b
 	.label basic_current_line_ptr = $3d
-	.alias basic_numeric_work_area $57 ; $57 - $60 inclusive = 10 bytes
+	// Note that the statement point is in the CHRGET/CHRGOT routine
 	// in ZP RAM.  (Compute's Mapping the 64, p25)
 	.label basic_current_statement_ptr = $7a
-	;; Floating point accumulator 1 $61 - $68
+	.label basic_numeric_work_area = $57 // $57 - $60 inclusive = 10 bytes
 	.alias basic_fac1_exponent $61
 	.alias basic_fac1_mantissa $62 ; $62 - $65
 	.alias basic_fac1_sign $66
 	.alias basic_fac1_overflow $68
 	.alias basic_fac1_mantissa_lob $70
-	.alias basic_fac2_exponent $69	
+	// Floating point accumulator 1 $61 - $68
-	.alias basic_fac2_mantissa $6A ; $6A - $6D
+	.label basic_fac1_exponent = $61
-	.alias basic_fac2_sign $6E
+	.label basic_fac1_mantissa = $62 // $62 - $65
 	.label basic_fac1_sign = $66
 	.label basic_fac1_overflow = $68
 	.label basic_fac1_mantissa_lob = $70
-	;; We also re-use FAC2 for memory move pointers, since
+	.label basic_fac2_exponent = $69
-	;; we can't be doing calculations while moving memory
+	.label basic_fac2_mantissa = $6A // $6A - $6D
-	.alias memmove_src $69
+	.label basic_fac2_sign = $6E
 	.alias memmove_dst $6b
 	.alias memmove_size $6d	
-	.alias current_file_num $98
+	// We also re-use FAC2 for memory move pointers, since
-	.alias cassette_buffer_bytes_used $A6
+	// we can't be doing calculations while moving memory
-	.alias load_or_scroll_temp_pointer $AC
+	.label memmove_src = $69
-	;; We also use the following for temp colour pointer when scrolling
+	.label memmove_dst = $6b
-	.alias load_save_verify_end_address $AE
+	.label memmove_size = $6d
-	.alias cassette_buffer_ptr $B2
+	.label current_file_num = $98
-	.alias current_logical_filenum $B8
+	.label cassette_buffer_bytes_used = $A6
-	.alias current_secondary_address $B9
+	.label load_or_scroll_temp_pointer = $AC
-	.alias current_device_number $BA
+	// We also use the following for temp colour pointer when scrolling
-	.alias current_filename_ptr $BB
+	.label load_save_verify_end_address = $AE
 	.alias load_save_start_ptr $C1
 	.alias load_save_end_ptr $C3
 	.alias last_key_matrix_position $C5
 	.alias keys_in_key_buffer $C6
 	.alias reverse_video_flag $C7
 	.alias end_of_input_line $C8
 	.alias start_of_keyboard_input $C9
 	.alias current_key_index_entry $CB
 	.alias cursor_blink_disable $CC
 	.alias cursor_blink_countdown $CD
 	.alias cursor_saved_character $CE
 	.alias cursor_is_visible $CF
 	.alias keyboard_input_ready $D0
 	.alias current_screen_line_ptr $D1
 	.alias current_screen_x $D3
 	.alias quote_mode_flag $D4
 	.alias logical_line_length $D5
 	.alias current_screen_y $D6
 	.alias last_printed_character_ascii $D7
 	.alias insert_mode $D8
 	; Bits 0 -3 = bits 8-11 of screen line address
 	; Bit 7 = line spans multiple physical lines
 	.alias screen_line_link_table $D9
 	.alias current_screen_line_colour_ptr $F3
 	.alias keyboard_decoding_table_ptr $F5
 	.alias rs232_rx_buffer_ptr $F7
 	.alias rs232_tx_buffer_ptr $F9
-	.alias basic_input_buffer BUF
+	.label cassette_buffer_ptr = $B2
 	.label current_logical_filenum = $B8
 	.label current_secondary_address = $B9
 	.label current_device_number = $BA
 	.label current_filename_ptr = $BB
 	.label load_save_start_ptr = $C1
 	.label load_save_end_ptr = $C3
 	.label last_key_matrix_position = $C5
 	.label keys_in_key_buffer = $C6
 	.label reverse_video_flag = $C7
 	.label end_of_input_line = $C8
 	.label start_of_keyboard_input = $C9
 	.label current_key_index_entry = $CB
 	.label cursor_blink_disable = $CC
 	.label cursor_blink_countdown = $CD
 	.label cursor_saved_character = $CE
 	.label cursor_is_visible = $CF
 	.label keyboard_input_ready = $D0
 	.label current_screen_line_ptr = $D1
 	.label current_screen_x = $D3
 	.label quote_mode_flag = $D4
 	.label logical_line_length = $D5
 	.label current_screen_y = $D6
 	.label last_printed_character_ascii = $D7
 	.label insert_mode = $D8
 	// Bits 0 -3 = bits 8-11 of screen line address
 	// Bit 7 = line spans multiple physical lines
 	.label screen_line_link_table = $D9
 	.label current_screen_line_colour_ptr = $F3
 	.label keyboard_decoding_table_ptr = $F5
 	.label rs232_rx_buffer_ptr = $F7
 	.label rs232_tx_buffer_ptr = $F9
-	; "Compute's Mapping the 64" book
+	.label basic_input_buffer = BUF
 	.alias keyboard_buffer $0277
 	.alias text_colour $0286 ; p55
 	.alias colour_under_cursor $0287 ; p56
 	.alias key_buffer_size $0289 ; p57
-	;; 0 = cursor keys, insert, delete and space repeat, but nothing else
+	// "Compute's Mapping the 64" book
-	;; 128 = all keys repeat
+	.label keyboard_buffer = $0277
-	;; 64 = no keys repeat
+	.label text_colour = $0286 // p55
-	.alias key_repeat_flags $028A ; p58
+	.label colour_under_cursor = $0287 // p56
-	;; https://www.c64-wiki.com/wiki/Page_2
+	.label key_buffer_size = $0289 // p57
 	.alias key_repeat_counter $028B
 	.alias key_first_repeat_delay $028C
 	;; bit 0 = shift, 1 = Vendor Key, 2 = Control
 	.alias key_bucky_state $028D
 	.alias key_last_bucky_state $028E
 	.alias keyboard_decoding_ptr $028F
 	.alias enable_case_switch $0291
 	.alias screen_scroll_disable $0292
-	;; BASIC uses some extra bytes for memory access under ROMs located at $2A7 onwards
+	// 0 = cursor keys, insert, delete and space repeat, but nothing else
-	;; IRQs are disabled when doing such accesses, and a default NMI handler only increments
+	// 128 = all keys repeat
-	;; a counter, so that if an NMI occurs, it doesn't crash the machine, but can be captured.
+	// 64 = no keys repeat
-	.alias missed_nmi_flag         $2A7
+	.label key_repeat_flags = $028A // p58
-	.alias tiny_nmi_handler		$2A8	
+	// https://www.c64-wiki.com/wiki/Page_2
-	.alias shift_mem_up tiny_nmi_handler+shift_mem_up_routine-tiny_nmi_handler_routine
+	.label key_repeat_counter = $028B
-	.alias shift_mem_down tiny_nmi_handler+shift_mem_down_routine-tiny_nmi_handler_routine
+	.label key_first_repeat_delay = $028C
-	.alias peek_under_roms tiny_nmi_handler+peek_under_roms_routine-tiny_nmi_handler_routine
+	// bit 0 = shift, 1 = Vendor Key, 2 = Control
-	.alias poke_under_roms tiny_nmi_handler+poke_under_roms_routine-tiny_nmi_handler_routine
+	.label key_bucky_state = $028D
-	.alias memmap_allram tiny_nmi_handler+memmap_allram_routine-tiny_nmi_handler_routine
+	.label key_last_bucky_state = $028E
-	.alias memmap_normal tiny_nmi_handler+memmap_normal_routine-tiny_nmi_handler_routine
+	.label keyboard_decoding_ptr = $028F
 	.label enable_case_switch = $0291
 	.label screen_scroll_disable = $0292
 	// BASIC uses some extra bytes for memory access under ROMs located at $2A7 onwards
 	// IRQs are disabled when doing such accesses, and a default NMI handler only increments
 	// a counter, so that if an NMI occurs, it doesn't crash the machine, but can be captured.
 	.label missed_nmi_flag = $2A7
 	.label tiny_nmi_handler = $2A8
 	.label shift_mem_up = tiny_nmi_handler+shift_mem_up_routine-tiny_nmi_handler_routine
 	.label shift_mem_down = tiny_nmi_handler+shift_mem_down_routine-tiny_nmi_handler_routine
 	.label peek_under_roms = tiny_nmi_handler+peek_under_roms_routine-tiny_nmi_handler_routine
 	.label poke_under_roms = tiny_nmi_handler+poke_under_roms_routine-tiny_nmi_handler_routine
 	.label memmap_allram = tiny_nmi_handler+memmap_allram_routine-tiny_nmi_handler_routine
 	.label memmap_normal = tiny_nmi_handler+memmap_normal_routine-tiny_nmi_handler_routine
@@ -1,9 +1,10 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_BANNER
+.macro TARGET_HOOK_BANNER() {
-	.byte "  OPEN ROMS, ", $00
+	.text "  OPEN ROMS, "
 	.byte $00
-.macend
+}
@@ -1,10 +1,10 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_BANNER
+.macro TARGET_HOOK_BANNER() {
-	;; New banner from Retrofan
+	// New banner from Retrofan
 	.byte $9a, $12, $20, $20, $7f, $a9, $20, $20, $1f, $20, $9a, $20, $20, $20
 	.byte $20, $1f, $20, $9a, $a9, $20, $20, $20, $92, $a1, $1f, $12, $20, $9a, $a9, $20
 	.byte $20, $20, $7f, $1f, $20, $20, $9a, $a3, $a3, $a3, $a3, $a3, $a3, $a3, $1f, $20
@@ -21,21 +21,21 @@
 	.byte $20, $20, $1f, $20, $20, $96, $a3, $a3, $a3, $a3, $1f
 	.byte $92, $0D, $0D, $05, $00
-	;; Original Deft-supplied banner
+	// Original Deft-supplied banner
-	;; .byte $9A,$12,$A3,$A3,$A3,$A3,$A3,$A3,$DF,$9B,$92,$20,$05,$12,$A0,$A0
+	// .byte $9A,$12,$A3,$A3,$A3,$A3,$A3,$A3,$DF,$9B,$92,$20,$05,$12,$A0,$A0
-	;; .byte $DF,$9B,$92,$20,$05,$12,$A0,$A0,$DF,$9B,$92,$20,$05,$12,$A0,$A0
+	// .byte $DF,$9B,$92,$20,$05,$12,$A0,$A0,$DF,$9B,$92,$20,$05,$12,$A0,$A0
-	;; .byte $DF,$9B,$92,$20,$05,$12,$A0,$A0,$DF,$9A,$92,$20,$05,$20,$20,$20
+	// .byte $DF,$9B,$92,$20,$05,$12,$A0,$A0,$DF,$9A,$92,$20,$05,$20,$20,$20
-	;; .byte $4D,$20,$45,$20,$47,$20,$41,$0D,$99,$12,$A3,$A3,$A3,$A3,$A3,$A3
+	// .byte $4D,$20,$45,$20,$47,$20,$41,$0D,$99,$12,$A3,$A3,$A3,$A3,$A3,$A3
-	;; .byte $A3,$DF,$92,$7F,$12,$CD,$CD,$DF,$92,$7F,$12,$DF,$05,$92,$20,$20
+	// .byte $A3,$DF,$92,$7F,$12,$CD,$CD,$DF,$92,$7F,$12,$DF,$05,$92,$20,$20
-	;; .byte $99,$7F,$12,$DF,$05,$92,$20,$20,$99,$7F,$12,$DF,$92,$7F,$12,$DF
+	// .byte $99,$7F,$12,$DF,$05,$92,$20,$20,$99,$7F,$12,$DF,$92,$7F,$12,$DF
-	;; .byte $05,$92,$20,$20,$99,$42,$20,$41,$20,$53,$20,$49,$20,$43,$0D,$9E
+	// .byte $05,$92,$20,$20,$99,$42,$20,$41,$20,$53,$20,$49,$20,$43,$0D,$9E
-	;; .byte $12,$A3,$A3,$A3,$A3,$A3,$A3,$A3,$A3,$DF,$9B,$92,$7F,$12,$DF,$92
+	// .byte $12,$A3,$A3,$A3,$A3,$A3,$A3,$A3,$A3,$DF,$9B,$92,$7F,$12,$DF,$92
-	;; .byte $7F,$12,$DF,$92,$7F,$12,$CD,$05,$92,$20,$20,$9B,$7F,$12,$CD,$92
+	// .byte $7F,$12,$DF,$92,$7F,$12,$CD,$05,$92,$20,$20,$9B,$7F,$12,$CD,$92
-	;; .byte $7F,$12,$DF,$92,$7F,$12,$CD,$92,$7F,$12,$DF,$9A,$92,$20,$05,$20
+	// .byte $7F,$12,$DF,$92,$7F,$12,$CD,$92,$7F,$12,$DF,$9A,$92,$20,$05,$20
-	;; .byte $9A,$2D,$2D,$2D,$2D,$2D,$2D,$2D,$0D,$96,$12,$A3,$A3,$A3,$A3,$A3
+	// .byte $9A,$2D,$2D,$2D,$2D,$2D,$2D,$2D,$0D,$96,$12,$A3,$A3,$A3,$A3,$A3
-	;; .byte $A3,$A3,$A3,$A3,$DF,$9A,$92,$7F,$12,$DF,$92,$7F,$9B,$20,$9A,$7F
+	// .byte $A3,$A3,$A3,$A3,$DF,$9A,$92,$7F,$12,$DF,$92,$7F,$9B,$20,$9A,$7F
-	;; .byte $12,$A0,$A0,$9B,$92,$20,$9A,$7F,$12,$A0,$A0,$9B,$92,$20,$9A,$7F
+	// .byte $12,$A0,$A0,$9B,$92,$20,$9A,$7F,$12,$A0,$A0,$9B,$92,$20,$9A,$7F
-	;; .byte $12,$DF,$92,$7F,$9B,$20,$9A,$20,$9B,"0.2.0.0",$0D
+	// .byte $12,$DF,$92,$7F,$9B,$20,$9A,$20,$9B,"0.2.0.0",$0D
-	;; .byte $0D,$05,$92,$00
+	// .byte $0D,$05,$92,$00
-.macend
+}
@@ -1,9 +1,12 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_BANNER
+.macro TARGET_HOOK_BANNER() {
-	.byte "  OPEN ROMS FOR ULTIMATE 64", $0D, $0D, "  ", $00
+	.text "  OPEN ROMS FOR ULTIMATE 64"
 	.byte $0D, $0D
 	.text "  "
 	.byte $00
-.macend
+}
@@ -1,3 +1,4 @@
-	;; Compute's Mapping the C64 p88
+// Compute's Mapping the C64 p88
 	.word basic_cold_start
@@ -1,2 +1,3 @@
-	;; Compute's Mapping the C64 p88
+// Compute's Mapping the C64 p88
 	.word basic_warm_start
@@ -1,6 +1,6 @@
-	;; Compute's Mapping the 64, p89
+// Compute's Mapping the 64, p89
-	;; 8 character name
+// 8 character name
-	;; MEGABAS2 = "MEGA BASIC 2"
+// MEGABAS2 = "MEGA BASIC 2"
 	.byte $4D,$45,$47,$41,$42,$41,$53,$32
@@ -1,19 +1,19 @@
-	;; Print string at $YYAA
+// Print string at $YYAA
-	;; Compute's Mapping the 64 p101
+// Compute's Mapping the 64 p101
 print_string:
-	;; Setup pointer	
+	// Setup pointer
 	sty temp_string_ptr+1
 	sta temp_string_ptr+0
 	txa	
 	pha
-	;; Get offset ready
+	// Get offset ready
 	ldy #$00
 print_string_loop:	
-	;; Save Y in X, since X is preserved by chrout, but Y is not
+	// Save Y in X, since X is preserved by chrout, but Y is not
 	tya
 	tax
@@ -28,7 +28,6 @@ print_string_loop:
 	iny
 	bne print_string_loop
 print_string_end:
 	pla
@@ -1,31 +1,31 @@
-	;; BASIC Cold start entry point
+// BASIC Cold start entry point
-	;; Compute's Mapping the 64 p211
+// Compute's Mapping the 64 p211
 basic_cold_start:	
-	;; Setup BASIC vectors at $0300
+	// Setup BASIC vectors at $0300
-	;; Initialise interpretor
+	// Initialise interpretor
-	;; Print start up message
+	// Print start up message
-	;; Print coloured part of the message
+	// Print coloured part of the message
-	;; ldy #>startup_message
+	// ldy #>startup_message
-	;; lda #<startup_message
+	// lda #<startup_message
-	;; jsr print_string
+	// jsr print_string
 	jsr printf // XXX don't use printf, keep it for debug purposes only
 	jsr printf
 ; Used 217 bytes
 startup_banner:
-	`TARGET_HOOK_BANNER
+	TARGET_HOOK_BANNER()
-	;; Print PAL/NTSC
+	// Print PAL/NTSC
-	ldx #30 ; NTSC
+	ldx #30 // NTSC
 	lda PALNTSC
-	beq +
+	beq !+
-	ldx #31 ; PAL
+	ldx #31 // PAL
-*
+!:
 	jsr print_packed_message
-	;; Work out free bytes, and display
+	// Work out free bytes, and display
 	jsr basic_do_new
 	lda basic_top_of_memory_ptr+0
 	sec
@@ -39,22 +39,21 @@ startup_banner:
 	lda #$20
 	jsr JCHROUT
-	;; Print the rest of the start up message
+	// Print the rest of the start up message
 	ldx #34
 	jsr print_packed_message
-	;; jump into warm start loop
+	// jump into warm start loop
 	jmp basic_warm_start
-
+startup_message: // XXX this is probably not needed anymore
-startup_message:
+	// Clear the screen
 	;; Clear the screen
 	.byte $93
-	;; Vertical bars in different colours
+	// Vertical bars in different colours
 	.byte $1C,$B4
 	.byte $9E,$B5
 	.byte $1E,$A1
-	;; <RVS><WHITE>MEGA<NORMAL>BASIC\r\r
+	// <RVS><WHITE>MEGA<NORMAL>BASIC\r\r
 	.byte $12,$05,$4D,$45,$47,$41,$92
 	.byte $42,$41,$53,$49,$43
 	.byte $20,$56,$32,$2e,$30,$2e,$30
@@ -1,18 +1,19 @@
-	;; Delete the current BASIC line, which is assumed to have already
+// Delete the current BASIC line, which is assumed to have already
-	;; been found with basic_find_line.
+// been found with basic_find_line.
-	;; Really only consists of copying memory down.
+// Really only consists of copying memory down.
-	;; The only complication is that we have to do the copy with ROMs
+// The only complication is that we have to do the copy with ROMs
-	;; banked out. Oh, yes, and we have to update all the links in
+// banked out. Oh, yes, and we have to update all the links in
-	;; the following basic lines.
+// the following basic lines.
 basic_delete_line:
-	;; jsr printf
+	// jsr printf
-	;; .byte "DELETING LINE AT $"
+	// .text "DELETING LINE AT $"
-	;; .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte $0d,0
+	// .byte $0d,0
-	;; Get address of next line
+	// Get address of next line
 	ldx #<basic_current_line_ptr
 	ldy #0
 	jsr peek_under_roms
@@ -21,7 +22,7 @@ basic_delete_line:
 	jsr peek_under_roms
 	sta tokenise_work4
-	;; Work out length of this line by looking at the pointer
+	// Work out length of this line by looking at the pointer
 	lda tokenise_work3
 	sec
 	sbc basic_current_line_ptr+0
@@ -30,31 +31,31 @@ basic_delete_line:
 	sbc basic_current_line_ptr+1
 	sta tokenise_work4
-	;; jsr printf
+	// jsr printf
-	;; .byte "LINE LENGTH IS $"
+	// .text "LINE LENGTH IS $"
-	;; .byte $f0,<tokenise_work4,>tokenise_work4
+	// .byte $f0,<tokenise_work4,>tokenise_work4
-	;; .byte $f0,<tokenise_work3,>tokenise_work3
+	// .byte $f0,<tokenise_work3,>tokenise_work3
-	;; .byte $0d,0
+	// .byte $0d,0
 	lda tokenise_work4
 	sbc #0
 	cmp #$00
-	beq +
+	beq !+
-	;; Line length is <0 or >255 bytes.
+	// Line length is <0 or >255 bytes.
-	;; Either way, things are bad, so abort.
+	// Either way, things are bad, so abort.
 	jmp do_MEMORY_CORRUPT_error
-*
+!:
-	;; Length can now be safely assumed to be in the low
+	// Length can now be safely assumed to be in the low
-	;; byte only, i.e., stored in tokenise_work3
+	// byte only, i.e., stored in tokenise_work3
 	lda tokenise_work3
 	pha
 	tax
-	;; Shuffle everything down
+	// Shuffle everything down
 	jsr basic_shift_mem_down_and_relink
-	;; Now decrease top of BASIC mem
+	// Now decrease top of BASIC mem
 	pla
 	sta tokenise_work3
 	lda basic_end_of_text_ptr+0
@@ -1,40 +1,37 @@
-	;; Compute's Mapping the 64 p93
+// Compute's Mapping the 64 p93
 basic_do_error:
-	;; Save error number
+	// Save error number
 	txa
 	pha
-	;; Print ? at start
+	// Print ? at start
-	lda #$0d
+	lda #$0D
 	jsr JCHROUT
-	lda #$3f
+	lda #$3F
 	jsr JCHROUT
-	;; Print main part of error message
+	// Print main part of error message
 	pla
 	tax
 	jsr print_packed_message
-	;; Print ERROR at end
+	// Print ERROR at end
 	lda #$20
 	jsr JCHROUT
 	ldx #33
 	jsr print_packed_message
-	;; XXX print IN if not in direct mode
+	// XXX print IN if not in direct mode
-	;; XXX print line number if not in direct mode
+	// XXX print line number if not in direct mode
-	lda #$0d
+	lda #$0D
 	jsr JCHROUT
-	lda #$0d
+	lda #$0D // XXX do we need this?
 	jsr JCHROUT
-	;; Reset stack, and go back to main loop
+	// Reset stack, and go back to main loop
-	ldx #$fe
+	ldx #$FE
 	txs
 	jmp basic_main_loop
@@ -1,13 +1,13 @@
-	;; Jump back into the BASIC execute line loop
+// Jump back into the BASIC execute line loop
-	;; after first checking that we have a colon
+// after first checking that we have a colon
-	;; or $00 char
+// or $00 char
 basic_end_of_statement_check:	
 	ldx #<basic_current_statement_ptr
 	ldy #0
 	jsr peek_under_roms
-	;; Consume any spaces
+	// Consume any spaces
 	cmp #$20
 	bne no_space_to_skip
 	jsr basic_consume_character
@@ -15,62 +15,62 @@ basic_end_of_statement_check:
 no_space_to_skip:
 	cmp #$00
-	beq +
+	beq !+
 	cmp #$3a
-	beq +
+	beq !+
-	;; not end of statement
+	// not end of statement
 	clc
 	rts
-*
+!:
 	sec
 	rts
 basic_execute_statement:
-	;; Check for RUN/STOP
+	// Check for RUN/STOP
 	lda STKEY
-	bmi +
+	bmi !+
 	jmp basic_do_break
-*
+!:
-	;; Skip over any white space and :
+	// Skip over any white space and :
 	ldy #0
 	ldx #<basic_current_statement_ptr
 	jsr peek_under_roms
 	jsr basic_end_of_statement_check
 	bcs basic_end_of_line
-	;; jsr printf
+	// jsr printf
-	;; .byte "LINE PTR = $"
+	// .text "LINE PTR = $"
-	;; .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte ", STATEMENT PTR = $"
+	// .text ", STATEMENT PTR = $"
-	;; .byte $f1,<basic_current_statement_ptr,>basic_current_statement_ptr
+	// .byte $f1,<basic_current_statement_ptr,>basic_current_statement_ptr
-	;; .byte $f0,<basic_current_statement_ptr,>basic_current_statement_ptr
+	// .byte $f0,<basic_current_statement_ptr,>basic_current_statement_ptr
-	;; .byte $d,0
+	// .byte $d,0
-	;; Go through the line until its end is reached.
+	// Go through the line until its end is reached.
-	;; If we reach the end are in direct mode, then
+	// If we reach the end are in direct mode, then
-	;; go back to reading input, else look for the
+	// go back to reading input, else look for the
-	;; next line, and advance to that, or else
+	// next line, and advance to that, or else
-	;; return to READY prompt because we have run out
+	// return to READY prompt because we have run out
-	;; of program.
+	// of program.
-	;; Get next char of program text, even if it is hiding under a ROM or the
+	// Get next char of program text, even if it is hiding under a ROM or the
-	;; IO area.
+	// IO area.
 	ldx #<basic_current_statement_ptr
 	ldy #0
 	jsr peek_under_roms
 	cmp #$00
 	beq basic_end_of_line
-	;; The checks should be done in order of frequency, so that we are as
+	// The checks should be done in order of frequency, so that we are as
-	;; fast as possible.
+	// fast as possible.
 	cmp #$7f
 	bcc not_a_token
-	;; It's a token: So get the jump table entry for it, push it on the stack
+	// It's a token: So get the jump table entry for it, push it on the stack
-	;; and then RTS to start it.
+	// and then RTS to start it.
 	asl
 	tax
 	lda basic_command_jump_table+1,x
@@ -78,42 +78,42 @@ basic_execute_statement:
 	lda basic_command_jump_table+0,x
 	pha
-	;; Now consume the character
+	// Now consume the character
 	jsr basic_consume_character
 	rts
 not_a_token:
-	;; Space, which we can also just ignore
+	// Space, which we can also just ignore
 	cmp #$20
 	beq basic_skip_char
-	;; End of line?
+	// End of line?
 	cmp #$00
 	beq basic_end_of_line
-	;; :, i.e., statement separator, which we can simply ignore
+	// :, i.e., statement separator, which we can simply ignore
 	cmp #$3a
 	beq basic_skip_char
-;; START wedge support
+// START wedge support
-	;; Are we in direct mode?
+	// Are we in direct mode?
-	;; DOS Wedge is a hacky solution (inelegant, but convenient),
+	// DOS Wedge is a hacky solution (inelegant, but convenient),
-	;; BASIC programmers should implement communication with drives
+	// BASIC programmers should implement communication with drives
-	;; the standard way, handling channels properly. Besides,
+	// the standard way, handling channels properly. Besides,
-	;; current implementation does not support characters under ROM
+	// current implementation does not support characters under ROM
 	ldx basic_current_line_number+1
 	cpx #$ff
-	bne +
+	bne !+
-	;; We are in direct mode, allow wedge to handle '@' sign
+	// We are in direct mode, allow wedge to handle '@' sign
-	;; XXX Maybe it should be allowed only as the first command?
+	// XXX Maybe it should be allowed only as the first command?
 	cmp #$40
-	bne +
+	bne !+
 	jsr basic_consume_character
 	jmp wedge_dos
-*
+!:
-;; END wedge support
+// END wedge support
-	;; If all else fails, it's a syntax error
+	// If all else fails, it's a syntax error
 	jmp do_SYNTAX_error
 basic_skip_char:
@@ -124,14 +124,14 @@ basic_fetch_and_consume_character:
 	ldy #0
 	ldx #<basic_current_statement_ptr
 	jsr peek_under_roms
-	;; FALL THROUGH
+	// FALL THROUGH
 basic_consume_character:
-	;; Advance basic text pointer
+	// Advance basic text pointer
 	inc basic_current_statement_ptr+0
-	bne +
+	bne !+
 	inc basic_current_statement_ptr+1
-*
+!:
 	rts
 basic_unconsume_character:
@@ -146,46 +146,46 @@ basic_unconsume_character:
 basic_end_of_line:
-	;; XXX - If not in direct mode, then advance to next line, if there is
+	// XXX - If not in direct mode, then advance to next line, if there is
-	;; one.
+	// one.
-	;; Are we in direct mode
+	// Are we in direct mode
 	lda basic_current_line_number+1
 	cmp #$ff
 	bne basic_not_direct_mode
-	;; Yes, we were in direct mode, so stop now
+	// Yes, we were in direct mode, so stop now
 	jmp basic_main_loop
 basic_not_direct_mode:
-	;; Copy line number to previous line number
+	// Copy line number to previous line number
 	lda basic_current_line_number+0
 	sta basic_previous_line_number+0
 	lda basic_current_line_number+1
 	sta basic_previous_line_number+1
-	;; Advance the basic line pointer to the next line
+	// Advance the basic line pointer to the next line
 	jsr basic_follow_link_to_next_line
-	;; Are we at the end of the program?
+	// Are we at the end of the program?
 	lda basic_current_line_ptr+0
 	ora basic_current_line_ptr+1
 	bne basic_execute_from_current_line
-	;; End of program found
+	// End of program found
 	jmp basic_main_loop
 basic_execute_from_current_line:
-	;; Check if pointer is null, if so, we are at the end of
+	// Check if pointer is null, if so, we are at the end of
-	;; the program.
+	// the program.
 	ldy #0
 	ldx #<basic_current_line_ptr
 	jsr peek_pointer_null_check
-	bcs +
+	bcs !+
-	;; End of program reached
+	// End of program reached
 	jmp basic_main_loop
-*
+!:
-	;; Skip pointer and line number to get address of first statement
+	// Skip pointer and line number to get address of first statement
 	lda basic_current_line_ptr+0
 	clc
 	adc #4
@@ -194,7 +194,7 @@ basic_execute_from_current_line:
 	adc #0
 	sta basic_current_statement_ptr+1
-	;; Store line number
+	// Store line number
 	ldx #<basic_current_line_ptr
 	ldy #2
 	jsr peek_under_roms
@@ -206,7 +206,7 @@ basic_execute_from_current_line:
 	jmp basic_execute_statement
 basic_command_jump_table:
-	;; $80 - $8F
+	// $80 - $8F
 	.word cmd_end-1
 	.word cmd_for-1
 	.word cmd_next-1
@@ -221,10 +221,10 @@ basic_command_jump_table:
 	.word cmd_if-1
 	.word cmd_restore-1
 	.word cmd_gosub-1
-	.word cmd_return	-1
+	.word cmd_return-1
 	.word cmd_rem-1
-	;; $90-$9F
+	// $90-$9F
 	.word cmd_stop-1
 	.word cmd_on-1
 	.word cmd_wait-1
@@ -242,7 +242,7 @@ basic_command_jump_table:
 	.word cmd_sys-1
 	.word cmd_open-1
-	;; $A0-$AF
+	// $A0-$AF
 	.word cmd_close-1
 	.word cmd_get-1
 	.word cmd_new-1
@@ -260,7 +260,7 @@ basic_command_jump_table:
 	.word cmd_exponent-1
 	.word cmd_and-1
-	;; $B0-$BF
+	// $B0-$BF
 	.word cmd_or-1
 	.word cmd_greater-1
 	.word cmd_equal-1
@@ -278,7 +278,7 @@ basic_command_jump_table:
 	.word cmd_cos-1
 	.word cmd_sin-1
-	;; $C0-$CF
+	// $C0-$CF
 	.word cmd_tan-1
 	.word cmd_atn-1
 	.word cmd_peek-1
@@ -291,13 +291,13 @@ basic_command_jump_table:
 	.word cmd_right-1
 	.word cmd_mid-1
 	.word cmd_go-1 	
-	;; Undefined tokens
+	// Undefined tokens
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
-	;; $D0-$DF
+	// $D0-$DF
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
@@ -315,7 +315,7 @@ basic_command_jump_table:
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
-	;; $E0-$EF
+	// $E0-$EF
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
@@ -333,7 +333,7 @@ basic_command_jump_table:
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
-	;; $F0-$FF
+	// $F0-$FF
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
@@ -350,4 +350,3 @@ basic_command_jump_table:
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
 	.word cmd_unimplemented-1
@@ -1,50 +1,50 @@
-	;; Find the BASIC line with number basic_line_number
+// Find the BASIC line with number basic_line_number
 basic_find_line:
-	;; Get pointer to start of BASIC text
+	// Get pointer to start of BASIC text
 	lda basic_start_of_text_ptr+0
 	sta basic_current_line_ptr+0
 	lda basic_start_of_text_ptr+1
 	sta basic_current_line_ptr+1
 basic_find_line_loop:	
-	;; Then search for line number
+	// Then search for line number
-	;; Line number
+	// Line number
 	ldy #3
 	ldx #<basic_current_line_ptr
 	jsr peek_under_roms
 	cmp basic_line_number+1
-	beq +
+	beq !+
 	bcs line_num_too_high
 	bne not_this_line
-*
+!:
 	dey
 	jsr peek_under_roms
 	cmp basic_line_number+0
-	beq +
+	beq !+
 	bcs line_num_too_high
 	bne not_this_line
-*
+!:
 	clc
 	rts
 not_this_line:
-	;; Not this line, so advance to next line
+	// Not this line, so advance to next line
 	ldx #<basic_current_line_ptr
 	jsr peek_pointer_null_check
 	bcs more_lines_exist
-	;; no more lines exist, return failure
+	// no more lines exist, return failure
 line_num_too_high:
 	sec
 	rts
 more_lines_exist:	
-	;; XXX - Add program mangled check here to be triggered
+	// XXX - Add program mangled check here to be triggered
-	;; if the link goes backwards.
+	// if the link goes backwards.
-	;; Follow link to next line
+	// Follow link to next line
 	ldy #0
 	ldx #<basic_current_line_ptr
 	jsr peek_under_roms
@@ -1,5 +1,5 @@
-	;; Advance basic_current_line_ptr by following the
+// Advance basic_current_line_ptr by following the
-	;; link to the next line
+// link to the next line
 basic_find_next_line:
@@ -1,25 +1,26 @@
-	;; Insert the tokenised line stored at $0200.
+// Insert the tokenised line stored at $0200.
-	;; First work out where in the list to put it
+// First work out where in the list to put it
-	;; (basic_find_line with the line number can be used to work
+// (basic_find_line with the line number can be used to work
-	;; out the insertion point, as it should abort once it finds a
+// out the insertion point, as it should abort once it finds a
-	;; line number too high).
+// line number too high).
-	;; Then all we have to do is push the rest of the BASIC text up,
+// Then all we have to do is push the rest of the BASIC text up,
-	;; and update the pointers in all following basic lines.
+// and update the pointers in all following basic lines.
 basic_insert_line:
-	;; ASSUMES basic_find_line has been called to set the insert point.
+	// ASSUMES basic_find_line has been called to set the insert point.
-	;; We need to insert space for the link link token, the line number,
+	// We need to insert space for the link link token, the line number,
-	;; and the zero-terminated line itself.  This means 2+2+1 plus length
+	// and the zero-terminated line itself.  This means 2+2+1 plus length
-	;; of tokenised string after the line number
+	// of tokenised string after the line number
-	;; But first, remember where the pointer will be, so that we can
+	// But first, remember where the pointer will be, so that we can
-	;; put the line in there after.
+	// put the line in there after.
-	;; jsr printf
+	// jsr printf
-	;; .byte "INSERTING LINE AT $"
+	// .text "INSERTING LINE AT $"
-	;; .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f1,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
+	// .byte $f0,<basic_current_line_ptr,>basic_current_line_ptr
-	;; .byte $0d,0
+	// .byte $0d,0
 	lda basic_current_line_ptr+0
 	pha
@@ -27,20 +28,20 @@ basic_insert_line:
 	pha
-	;; Get number of bytes in tokenised line after line number
+	// Get number of bytes in tokenised line after line number
 	lda tokenise_work2
 	sec
 	sbc tokenise_work1
-	;; Add on the four bytes space we need
+	// Add on the four bytes space we need
 	clc
 	adc #5
 	pha
 	tax
-	;; Make the space
+	// Make the space
 	jsr basic_shift_mem_up_and_relink
-	;; Now increase top of BASIC mem
+	// Now increase top of BASIC mem
 	pla
 	clc
 	adc basic_end_of_text_ptr+0
@@ -49,13 +50,13 @@ basic_insert_line:
 	adc #0
 	sta basic_end_of_text_ptr+1
-	;; Get pointer back
+	// Get pointer back
 	pla
 	sta basic_current_line_ptr+1
 	pla
 	sta basic_current_line_ptr+0
-	;; Write the line number
+	// Write the line number
 	ldy #2
 	ldx #<basic_current_line_ptr
 	lda basic_line_number+0
@@ -64,7 +65,7 @@ basic_insert_line:
 	lda basic_line_number+1
 	jsr poke_under_roms
-	;; Now store the line body itself
+	// Now store the line body itself
 	inc tokenise_work2
 line_store_loop:
 	ldx tokenise_work1
@@ -1,43 +1,43 @@
 basic_main_loop:
-	;; XXX - Check if direct or program mode, and get next line of input
+	// XXX - Check if direct or program mode, and get next line of input
-	;; the appropriate way.
+	// the appropriate way.
-	;; XXX - For now, it is hard coded to direct mode
+	// XXX - For now, it is hard coded to direct mode
-	;; Tell user we are ready
+	// Tell user we are ready
 	jsr ready_message
 basic_read_next_line:	
-	;; Read a line of input
+	// Read a line of input
 	ldx #$00
 read_line_loop:
-	jsr $ffcf 		; KERNAL CHRIN
+	jsr JCHRIN
 	bcs read_line_loop
 	cmp #$0d
 	beq got_line_of_input
-	;; Not carriage return, so try to append to line so far
+	// Not carriage return, so try to append to line so far
 	cpx #80
-	bcc +
+	bcc !+
-	;; Report STRING TOO LONG error (Compute's Mapping the 64 p93)
+	// Report STRING TOO LONG error (Compute's Mapping the 64 p93)
 	ldx #22
 	jmp basic_do_error
-*
+!:
 	sta basic_input_buffer,x
 	inx
 	jmp read_line_loop
 got_line_of_input:
-	;; Store length of input buffer ready for tokenising
+	// Store length of input buffer ready for tokenising
 	stx tokenise_work1
-	;; Strip leading spaces from the line
+	// Strip leading spaces from the line
 remove_leading_spaces:	
 	lda $0200
 	cmp #$20
-	bne +
+	bne !+
 	ldx #1
 rsl_l1:	lda $0200,x
 	sta $01ff,x
@@ -45,40 +45,40 @@ rsl_l1:	lda $0200,x
 	cpx tokenise_work1
 	bne rsl_l1
-	;; Reduce length of input by one
+	// Reduce length of input by one
 	dec tokenise_work1
-	;; Stop trying to rim if we run out of input
+	// Stop trying to rim if we run out of input
 	bne remove_leading_spaces
-*	
+!:
-	;; Do printing of the new line
+	// Do printing of the new line
 	lda #$0d
 	jsr JCHROUT
-	;; Ignore empty lines
+	// Ignore empty lines
 	lda tokenise_work1
 	beq basic_read_next_line
-	;; Else, tokenise the line
+	// Else, tokenise the line
 	jsr tokenise_line	
-	;; Has the user entered a line of BASIC beginning with a number?
+	// Has the user entered a line of BASIC beginning with a number?
 	lda $0200
 	cmp #$30
 	bcc not_a_line
 	cmp #$39
 	bcs not_a_line
-	;; Yes, the line begins with a number.
+	// Yes, the line begins with a number.
-	;; Parse the line number and check validity
+	// Parse the line number and check validity
-	;; injest_number follows tokenise_work1 as the offset into the line,
+	// injest_number follows tokenise_work1 as the offset into the line,
-	;; so remember the line length somewhere else for now.
+	// so remember the line length somewhere else for now.
 	lda tokenise_work1
 	sta tokenise_work2
 	lda #$00
 	sta tokenise_work1
-	;; Try to read line number
+	// Try to read line number
 	lda #<$0200
 	sta basic_current_statement_ptr+0
 	lda #>$0200
@@ -86,67 +86,66 @@ rsl_l1:	lda $0200,x
 	jsr basic_parse_line_number
-	;; Get pointer to next char
+	// Get pointer to next char
 	lda basic_current_statement_ptr+0
 	sta tokenise_work1
-	;; Got a valid line number -- so do add/del line
+	// Got a valid line number -- so do add/del line
-	;; Skip any spaces after the line number
+	// Skip any spaces after the line number
 	ldx tokenise_work1
 skip_spaces:	
 	lda $0200,x
 	cmp #$20
-	bne +
+	bne !+
 	inx
 	bne skip_spaces
-*	stx tokenise_work1
+!:	stx tokenise_work1
-	;; First, clear all variables, so that we only have to shove BASIC text around.
+	// First, clear all variables, so that we only have to shove BASIC text around.
-	;; (We could later remove this requirement, and the only effect should be
+	// (We could later remove this requirement, and the only effect should be
-	;; to slow things down, and that you might have to either CLR if there is no
+	// to slow things down, and that you might have to either CLR if there is no
-	;; memory free, or else it would auto CLR when you ran out of program space).
+	// memory free, or else it would auto CLR when you ran out of program space).
 	jsr basic_do_clr
-	;; Delete line if present
+	// Delete line if present
 	jsr basic_find_line
-	bcs +
+	bcs !+
-	;; Delete the line, whether we are deleting or
+	// Delete the line, whether we are deleting or
-	;; replacing the line
+	// replacing the line
 	jsr basic_delete_line
-*
+!:
-	;; Insert new line if non-zero length, i.e., that
+	// Insert new line if non-zero length, i.e., that
-	;; we are not just deleting the line.
+	// we are not just deleting the line.
 	lda tokenise_work1
 	cmp tokenise_work2
-	beq +
+	beq !+
 	jsr basic_insert_line
-*
+!:
-	;; No READY message after entering or deleting a line of BASIC
+	// No READY message after entering or deleting a line of BASIC
 	jmp basic_read_next_line
 not_a_line:	
-	;;  Actually interpret the line
+	//  Actually interpret the line
-	;; Setup pointer to the statement
+	// Setup pointer to the statement
 	lda #<$0200
 	sta basic_current_statement_ptr+0
 	lda #>$0200
 	sta basic_current_statement_ptr+1
-	;; There is no stored line, so zero that pointer out
+	// There is no stored line, so zero that pointer out
 	lda #$00
 	sta basic_current_line_ptr+0
 	sta basic_current_line_ptr+1
-	;; Put invalid line number in current line number value,
+	// Put invalid line number in current line number value,
-	;; so that we know we are in direct mode
+	// so that we know we are in direct mode
-	;; (Compute's Mapping the 64 p19)
+	// (Compute's Mapping the 64 p19)
 	lda #$ff
 	sta basic_current_line_number+1
 	jmp basic_execute_statement
@@ -3,22 +3,22 @@ basic_parse_line_number:
 	jsr injest_number
-	;; Check if the number is a valid line number
+	// Check if the number is a valid line number
-	;; i.e., 16 bits, no exponent, no decimal
+	// i.e., 16 bits, no exponent, no decimal
 	lda basic_fac1_mantissa+2
 	ora basic_fac1_mantissa+3
 	ora basic_fac1_exponent
-	beq +
+	beq !+
 ml_bad_line_number:
-	;; Invalid line number
+	// Invalid line number
 	jmp do_ILLEGAL_QUANTITY_error
-*	
+!:
-	;; Line number are not allowed to have decimal points in them
+	// Line number are not allowed to have decimal points in them
 	lda tokenise_work4
-	cmp #$ff
+	cmp #$FF
 	bne ml_bad_line_number
-	;; Got a valid line number.
+	// Got a valid line number.
 	lda basic_fac1_mantissa+0
 	sta basic_line_number+0
 	lda basic_fac1_mantissa+1
@@ -1,16 +1,16 @@
 basic_shift_mem_down_and_relink:
-	;; Shift memory down to basic_current_line_pointer
+	// Shift memory down to basic_current_line_pointer
-	;; from X bytes further along.
+	// from X bytes further along.
-	;; Destination is basic_current_line_ptr
+	// Destination is basic_current_line_ptr
 	lda basic_current_line_ptr+0
 	sta memmove_dst+0
 	lda basic_current_line_ptr+1
 	sta memmove_dst+1	
-	;; Source is that plus X
+	// Source is that plus X
 	txa
-	pha 			; also keep for later
+	pha 			// also keep for later
 	clc
 	adc basic_current_line_ptr+0
 	sta memmove_src+0
@@ -18,7 +18,7 @@ basic_shift_mem_down_and_relink:
 	adc #0
 	sta memmove_src+1
-	;; Size is distance from source to end of BASIC text.
+	// Size is distance from source to end of BASIC text.
 	lda basic_end_of_text_ptr+0
 	sec
 	sbc memmove_src+0
@@ -27,32 +27,32 @@ basic_shift_mem_down_and_relink:
 	sbc memmove_src+1
 	sta memmove_size+1
-	;; jsr printf
+	// jsr printf
-	;; .byte "TOP OF BASIC = $"
+	// .text "TOP OF BASIC = $"
-	;; .byte $f1,<basic_end_of_text_ptr,>basic_end_of_text_ptr
+	// .byte $f1,<basic_end_of_text_ptr,>basic_end_of_text_ptr
-	;; .byte $f0,<basic_end_of_text_ptr,>basic_end_of_text_ptr
+	// .byte $f0,<basic_end_of_text_ptr,>basic_end_of_text_ptr
-	;; .byte $0d
+	// .byte $0d
-	;; .byte "SHIFTING DOWN $"
+	// .text "SHIFTING DOWN $"
-	;; .byte $f1,<memmove_size,>memmove_size
+	// .byte $f1,<memmove_size,>memmove_size
-	;; .byte $f0,<memmove_size,>memmove_size
+	// .byte $f0,<memmove_size,>memmove_size
-	;; .byte " BYTES FROM $"
+	// .text " BYTES FROM $"
-	;; .byte $f1,<memmove_src,>memmove_src
+	// .byte $f1,<memmove_src,>memmove_src
-	;; .byte $f0,<memmove_src,>memmove_src
+	// .byte $f0,<memmove_src,>memmove_src
-	;; .byte " TO $"
+	// .text " TO $"
-	;; .byte $f1,<memmove_dst,>memmove_dst
+	// .byte $f1,<memmove_dst,>memmove_dst
-	;; .byte $f0,<memmove_dst,>memmove_dst
+	// .byte $f0,<memmove_dst,>memmove_dst
-	;; .byte $0d,0
+	// .byte $0d,0
-	;; The copy routine that copies under the ROMs is as simple
+	// The copy routine that copies under the ROMs is as simple
-	;; as possible to be as small as possible, so we have
+	// as possible to be as small as possible, so we have
-	;; to adjust the pointers and counts so that the simple
+	// to adjust the pointers and counts so that the simple
-	;; increment and decrement bounds checks work.
+	// increment and decrement bounds checks work.
-	;; Specifically we want Y pre-set so that the end of the
+	// Specifically we want Y pre-set so that the end of the
-	;; copy ends when Y = $00.
+	// copy ends when Y = $00.
-	;; So if copying 1 byte, we want Y=$FF
+	// So if copying 1 byte, we want Y=$FF
-	;; This means we have to then reduce the source and
+	// This means we have to then reduce the source and
-	;; target pointers by the same amount
+	// target pointers by the same amount
 	lda memmove_size+0
 	eor #$ff
@@ -75,50 +75,50 @@ basic_shift_mem_down_and_relink:
 	sbc #0
 	sta memmove_dst+1
-	;; Increase copy page count so we can post-decrement compare with $00
+	// Increase copy page count so we can post-decrement compare with $00
 	inc memmove_size+1
-	;; jsr printf
+	// jsr printf
-	;; .byte "REVISED BOUNDS $"
+	// .text "REVISED BOUNDS $"
-	;; .byte $f1,<memmove_size,>memmove_size
+	// .byte $f1,<memmove_size,>memmove_size
-	;; .byte $f0,<memmove_size,>memmove_size
+	// .byte $f0,<memmove_size,>memmove_size
-	;; .byte " BYTES FROM $"
+	// .text " BYTES FROM $"
-	;; .byte $f1,<memmove_src,>memmove_src
+	// .byte $f1,<memmove_src,>memmove_src
-	;; .byte $f0,<memmove_src,>memmove_src
+	// .byte $f0,<memmove_src,>memmove_src
-	;; .byte " TO $"
+	// .text " TO $"
-	;; .byte $f1,<memmove_dst,>memmove_dst
+	// .byte $f1,<memmove_dst,>memmove_dst
-	;; .byte $f0,<memmove_dst,>memmove_dst
+	// .byte $f0,<memmove_dst,>memmove_dst
-	;; .byte $0d,0
+	// .byte $0d,0
-	;; Get Y value ready for the copy
+	// Get Y value ready for the copy
 	ldy memmove_size+0
 	jsr shift_mem_down
-	;; Get length of deletion back
+	// Get length of deletion back
 	pla
 	sta tokenise_work3
-	;; Check if we still have any lines left
+	// Check if we still have any lines left
 	ldy #0
 	ldx #<basic_current_line_ptr
 	jsr peek_pointer_null_check
 	bcs relink_down_next_line
-	;; Nope, so just return
+	// Nope, so just return
 	clc
 	rts
 relink_down_next_line:
-	;; inc $d020
+	// inc $d020
-	;; jmp relink_down_next_line
+	// jmp relink_down_next_line
-	;; Subtract tokenise_work3 from the pointer
+	// Subtract tokenise_work3 from the pointer
 	ldy #0
 	ldx #<basic_current_line_ptr+0
 	jsr peek_under_roms
 	sec
-	sbc tokenise_Work3
+	sbc tokenise_work3
 	sta memmove_src+0
 	iny
 	jsr peek_under_roms
@@ -134,13 +134,13 @@ relink_down_next_line:
 	jsr poke_under_roms
 relink_down_loop:	
-	;; Now advance pointer to the next line,
+	// Now advance pointer to the next line,
 	lda memmove_src+0
 	sta basic_current_line_ptr+0
 	lda memmove_src+1
 	sta basic_current_line_ptr+1
-	;; Have we run out of lines to patch?
+	// Have we run out of lines to patch?
 	ldx #<basic_current_line_ptr
 	jsr peek_pointer_null_check
 	bcs relink_down_next_line
@@ -1,12 +1,12 @@
 basic_shift_mem_up_and_relink:
-	;; Shift memory up from basic_current_line_ptr
+	// Shift memory up from basic_current_line_ptr
-	;; X bytes.
+	// X bytes.
-	;; NOTE: Pointers need to be reduced by one, due to the way
+	// NOTE: Pointers need to be reduced by one, due to the way
-	;; the copyroutine works, so we do that here.
+	// the copyroutine works, so we do that here.
-	;; Work out end point of destination
+	// Work out end point of destination
 	txa
 	clc
 	adc basic_end_of_text_ptr+0
@@ -22,7 +22,7 @@ basic_shift_mem_up_and_relink:
 	sbc #0
 	sta memmove_dst+1
-	;; End point of source is just current end of BASIC text
+	// End point of source is just current end of BASIC text
 	lda basic_end_of_text_ptr+0
 	sec
 	sbc #1
@@ -31,7 +31,7 @@ basic_shift_mem_up_and_relink:
 	sbc #0
 	sta memmove_src+1
-	;; Work out size of region to copy
+	// Work out size of region to copy
 	lda basic_end_of_text_ptr+0
 	sec
 	sbc basic_current_line_ptr+0
@@ -40,25 +40,25 @@ basic_shift_mem_up_and_relink:
 	sbc basic_current_line_ptr+1
 	sta memmove_size+1
-	;; jsr printf
+	// jsr printf
-	;; .byte "TOP OF BASIC = $"
+	// .text "TOP OF BASIC = $"
-	;; .byte $f1,<basic_end_of_text_ptr,>basic_end_of_text_ptr
+	// .byte $f1,<basic_end_of_text_ptr,>basic_end_of_text_ptr
-	;; .byte $f0,<basic_end_of_text_ptr,>basic_end_of_text_ptr
+	// .byte $f0,<basic_end_of_text_ptr,>basic_end_of_text_ptr
-	;; .byte $0d
+	// .byte $0d
-	;; .byte "SHIFTING UP $"
+	// .text "SHIFTING UP $"
-	;; .byte $f1,<memmove_size,>memmove_size
+	// .byte $f1,<memmove_size,>memmove_size
-	;; .byte $f0,<memmove_size,>memmove_size
+	// .byte $f0,<memmove_size,>memmove_size
-	;; .byte " BYTES FROM $"
+	// .text " BYTES FROM $"
-	;; .byte $f1,<memmove_src,>memmove_src
+	// .byte $f1,<memmove_src,>memmove_src
-	;; .byte $f0,<memmove_src,>memmove_src
+	// .byte $f0,<memmove_src,>memmove_src
-	;; .byte " TO $"
+	// .text " TO $"
-	;; .byte $f1,<memmove_dst,>memmove_dst
+	// .byte $f1,<memmove_dst,>memmove_dst
-	;; .byte $f0,<memmove_dst,>memmove_dst
+	// .byte $f0,<memmove_dst,>memmove_dst
-	;; .byte $0d,0
+	// .byte $0d,0
-	;; To make life simple for the copy routine that lives in RAM,
+	// To make life simple for the copy routine that lives in RAM,
-	;; we have to adjust the end pointers down one page and set Y to the low
+	// we have to adjust the end pointers down one page and set Y to the low
-	;; byte of the copy size.
+	// byte of the copy size.
 	lda memmove_src+0
 	sec
 	sbc memmove_size+0
@@ -75,35 +75,35 @@ basic_shift_mem_up_and_relink:
 	sbc #0
 	sta memmove_dst+1
-	;; Now make exit easy, by being able to check for zero on size high byte when done
+	// Now make exit easy, by being able to check for zero on size high byte when done
 	inc memmove_size+1	
-	;; Then set Y to the number offset required
+	// Then set Y to the number offset required
 	ldy memmove_size+0
 	iny
 	stx tokenise_work3
-	;; jsr printf
+	// jsr printf
-	;; .byte "REVISED BOUNDS $"
+	// .text "REVISED BOUNDS $"
-	;; .byte $f1,<memmove_size,>memmove_size
+	// .byte $f1,<memmove_size,>memmove_size
-	;; .byte $f0,<memmove_size,>memmove_size
+	// .byte $f0,<memmove_size,>memmove_size
-	;; .byte " BYTES FROM $"
+	// .text " BYTES FROM $"
-	;; .byte $f1,<memmove_src,>memmove_src
+	// .byte $f1,<memmove_src,>memmove_src
-	;; .byte $f0,<memmove_src,>memmove_src
+	// .byte $f0,<memmove_src,>memmove_src
-	;; .byte " TO $"
+	// .text " TO $"
-	;; .byte $f1,<memmove_dst,>memmove_dst
+	// .byte $f1,<memmove_dst,>memmove_dst
-	;; .byte $f0,<memmove_dst,>memmove_dst
+	// .byte $f0,<memmove_dst,>memmove_dst
-	;; .byte $0d,0
+	// .byte $0d,0
-	;; Do the copy
+	// Do the copy
 	jsr shift_mem_up
-	;; Now fix the pointer to the next line
+	// Now fix the pointer to the next line
-	;; First, we need to point the current BASIC line
+	// First, we need to point the current BASIC line
-	;; pointer to itself, so that we can add the shift
+	// pointer to itself, so that we can add the shift
-	;; to make it end up pointing to the next line
+	// to make it end up pointing to the next line
 	ldy #0
 	ldx #<basic_current_line_ptr+0
 	lda basic_current_line_ptr+0
@@ -113,10 +113,10 @@ basic_shift_mem_up_and_relink:
 	jsr poke_under_roms
 relink_up_next_line:
-	;; inc $d020
+	// inc $d020
-	;; jmp relink_up_next_line
+	// jmp relink_up_next_line
-	;; Advance pointer by tokenise_word3 bytes
+	// Advance pointer by tokenise_word3 bytes
 	ldy #0
 	ldx #<basic_current_line_ptr+0
 	jsr peek_under_roms
@@ -132,20 +132,20 @@ relink_up_next_line:
 	adc #0
 	sta memmove_src+1
-	;; jsr printf
+	// jsr printf
-	;; .byte "LINE ADDR = $"
+	// .text "LINE ADDR = $"
-	;; .byte $f1,<basic_current_line_ptr,>basic_end_of_text_ptr
+	// .byte $f1,<basic_current_line_ptr,>basic_end_of_text_ptr
-	;; .byte $f0,<basic_current_line_ptr,>basic_end_of_text_ptr
+	// .byte $f0,<basic_current_line_ptr,>basic_end_of_text_ptr
-	;; .byte $d,"  BEFORE = $"
+	// .text $d,"  BEFORE = $"
-	;; .byte $f1,<memmove_dst,>memmove_dst
+	// .byte $f1,<memmove_dst,>memmove_dst
-	;; .byte $f0,<memmove_dst,>memmove_dst	
+	// .byte $f0,<memmove_dst,>memmove_dst	
-	;; .byte ",  AFTER = $"
+	// .text ",  AFTER = $"
-	;; .byte $f1,<memmove_src,>memmove_src
+	// .byte $f1,<memmove_src,>memmove_src
-	;; .byte $f0,<memmove_src,>memmove_src
+	// .byte $f0,<memmove_src,>memmove_src
-	;; .byte $d
+	// .byte $d
-	;; .byte 0
+	// .byte 0
-	;; Write memmove_src back to current line pointer
+	// Write memmove_src back to current line pointer
 	ldy #0
 	ldx #<basic_current_line_ptr
 	lda memmove_src+0
@@ -156,13 +156,13 @@ relink_up_next_line:
 relink_up_loop:	
-	;; Now advance pointer to the next line,
+	// Now advance pointer to the next line,
 	lda memmove_src+0
 	sta basic_current_line_ptr+0
 	lda memmove_src+1
 	sta basic_current_line_ptr+1
-	;; Have we run out of lines to patch?
+	// Have we run out of lines to patch?
 	ldx #<basic_current_line_ptr
 	jsr peek_pointer_null_check
 	bcs relink_up_next_line
@@ -1,12 +1,12 @@
-	;; Clear screen etc, show READY prompt.
+// Clear screen etc, show READY prompt.
 basic_warm_start:
 	jsr install_ram_routines
-	;; If warm start caused by BRK, print it address
+	// If warm start caused by BRK, print it address
 	lda CMP0
 	ora CMP0+1
-	beq +
+	beq !+
 	ldx #32
 	jsr print_packed_message
@@ -18,6 +18,6 @@ basic_warm_start:
 	lda #$0D
 	jsr JCHROUT
-*
+!:
 	jmp basic_main_loop
@@ -1,4 +1,3 @@
-	;; Skip the gap between $C000-$DFFF
+// Skip the gap between $C000-$DFFF
-	.checkpc $C000
+
-	.advance $DFFF,$00
+	.fill $2000, $00
 	.checkpc $E000
@@ -1,23 +1,24 @@
 cmd_stop:	
 basic_do_break:
-	jsr printf
+	jsr printf // XXX don't use printf, use packed messages!
-	.byte "BREAK",0
+	.text "BREAK"
 	.byte 0
-	;; Check for direct mode
+	// Check for direct mode
-	;; Are we in direct mode
+	// Are we in direct mode
 	lda basic_current_line_number+1
-	cmp #$ff
+	cmp #$FF
-	beq +
+	beq !+
-	;; Not direct mode
+	// Not direct mode
-	jsr printf
+	jsr printf // XXX don't use printf, use packed messages!
-	.byte " IN ",0
+	.text " IN "
 	.byte 0
 	lda basic_current_line_number+1
 	ldx basic_current_line_number+0
 	jsr print_integer
-*
+!:
-	lda #$0d
+	lda #$0D
 	jsr JCHROUT
 cmd_end:
 	jmp basic_main_loop
@@ -1,9 +1,9 @@
-	;; LIST basic text.
+// LIST basic text.
-	;; XXX - Doesn't currently support line number ranges
+// XXX - Doesn't currently support line number ranges
 cmd_list:
-	;; Set current line pointer to start of memory
+	// Set current line pointer to start of memory
 	lda basic_start_of_text_ptr+0
 	sta basic_current_line_ptr+0
 	lda basic_start_of_text_ptr+1
@@ -16,23 +16,23 @@ list_loop:
 	cmp #$00
 	bne list_more_lines
-	;; LIST terminates any running program,
+	// LIST terminates any running program,
-	;; because it has fiddled with the current line pointer.
+	// because it has fiddled with the current line pointer.
-	;; (Confirmed by testing on a C64)
+	// (Confirmed by testing on a C64)
 	jmp basic_main_loop
 list_more_lines:
 	lda STKEY
-	bmi +
+	bmi !+
 	jmp basic_do_break
-*
+!:
 	jsr list_single_line
-	;; Now link to the next line
+	// Now link to the next line
 	jsr basic_find_next_line
 	jmp list_loop
-list_single_line: ; entry point needed by DOS wedge
+list_single_line: // entry point needed by DOS wedge
-	;; Print line number
+	// Print line number
 	ldy #3
 	jsr peek_under_roms
 	pha
@@ -44,8 +44,8 @@ list_single_line: ; entry point needed by DOS wedge
 	lda #$20
 	jsr JCHROUT
-	;; Iterate through printing out the line
+	// Iterate through printing out the line
-	;; contents
+	// contents
 	lda #0
 	sta quote_mode_flag
@@ -63,34 +63,34 @@ list_print_loop:
 	lda #$22
 	jmp list_is_literal
 list_not_quote:	
-	;; Check quote mode, and display as literal if required
+	// Check quote mode, and display as literal if required
 	ldx quote_mode_flag
 	bne list_is_literal
 	cmp #$7f
 	bcc list_is_literal
-	;; Display a token
+	// Display a token
-	;; Save registers
+	// Save registers
 	tax
 	pha
 	tya
 	pha
-	;; Get pointer to compressed keyword list
+	// Get pointer to compressed keyword list
 	lda #<packed_keywords
 	sta temp_string_ptr+0
 	lda #>packed_keywords
 	sta temp_string_ptr+1
-	;; Subtract $80 from token to get offset in word
+	// Subtract $80 from token to get offset in word
-	;; list
+	// list
 	txa
 	and #$7f
 	tax
-	;; Now ask for it to be printed
+	// Now ask for it to be printed
 	ldy #$ff
 	jsr packed_word_search
@@ -100,11 +100,11 @@ list_not_quote:
 	cmp #$8f
 	bne list_not_rem
-	;; REM command locks quote flag on until the end of the line, allowing
+	// REM command locks quote flag on until the end of the line, allowing
-	;; funny characters in REM statements without problem.
+	// funny characters in REM statements without problem.
 	inc $0427
-	sta quote_mode_flag 	; Any value other than $00 or $FF will lock quote mode on, so the token value of REM is fine here
+	sta quote_mode_flag 	// Any value other than $00 or $FF will lock quote mode on, so the token value of REM is fine here
-	;; FALL THROUGH
+	// FALL THROUGH
 list_not_rem:		
 	iny
@@ -116,10 +116,10 @@ list_is_literal:
 	bne list_print_loop
 list_end_of_line:
-	;; Clear reverse flag
+	// Clear reverse flag
 	lda #$92
 	jsr JCHROUT
-	;; Print end of line
+	// Print end of line
 	lda #$0d
 	jsr JCHROUT
 	rts
@@ -1,64 +1,64 @@
 cmd_load:
-	;; Parse filename
+	// Parse filename
-	;; (we can tell the KERNAL where it is in memory directly, since the
+	// (we can tell the KERNAL where it is in memory directly, since the
-	;; KERNAL will be able to peek under ROMs to read it, since it will have
+	// KERNAL will be able to peek under ROMs to read it, since it will have
-	;; to be able to peek under the ROMs for SAVE and VERIFY).
+	// to be able to peek under the ROMs for SAVE and VERIFY).
-	;; Parse optional device #
+	// Parse optional device #
-	;; Parse optional secondary address
+	// Parse optional secondary address
-	;; XXX - C64 BASIC apparently doesn't clear variables after a LOAD in the
+	// XXX - C64 BASIC apparently doesn't clear variables after a LOAD in the
-	;; middle of a program. For safety, we do.
+	// middle of a program. For safety, we do.
 	jsr basic_do_clr
-	;; Setup Kernal to print control messages or not
+	// Setup Kernal to print control messages or not
-	lda #$80 ; display control messages and omit error messages
+	lda #$80 // display control messages and omit error messages
 	ldx basic_current_line_number+1
 	cpx #$FF
-	beq +
+	beq !+
-	lda #$00 ; direct mode - don't display anything
+	lda #$00 // direct mode - don't display anything
-*
+!:
 	jsr JSETMSG
-	;; Set filename and length
+	// Set filename and length
 	lda #$00
 	sta FNLEN
-	;; Without tape support, LOAD must have a filename
+	// Without tape support, LOAD must have a filename
-	;; (This also skips any leading spaces)
+	// (This also skips any leading spaces)
 	jsr basic_end_of_statement_check
-	bcc +
+	bcc !+
 	jmp do_MISSING_FILENAME_error
-*
+!:
 	jsr basic_fetch_and_consume_character
 	cmp #$22
-	beq +
+	beq !+
-	jmp do_SYNTAX_ERROR
+	jmp do_SYNTAX_error
-*
+!:
-	;; Filename starts here so set pointer
+	// Filename starts here so set pointer
 	lda basic_current_statement_ptr+0
 	sta current_filename_ptr+0
 	lda basic_current_statement_ptr+1
 	sta current_filename_ptr+1
-	;; Now search for end of line or closing quote
+	// Now search for end of line or closing quote
-	;; so that we know the length of the filename
+	// so that we know the length of the filename
 getting_filename:
 	jsr basic_fetch_and_consume_character
 	cmp #$22
 	beq got_filename
 	cmp #$00
-	bne +
+	bne !+
 	jsr basic_unconsume_character
 	jmp got_filename
-*
+!:
 	inc FNLEN
 	jmp getting_filename
 got_filename:
-	;; Now fetch the file number, start from the default one
+	// Now fetch the file number, start from the default one
 	jsr select_device
 	stx current_device_number
 	jsr injest_comma
@@ -66,116 +66,116 @@ got_filename:
 	jsr basic_parse_line_number
 	lda basic_line_number+1
-	beq +
+	beq !+
 	jmp do_ILLEGAL_QUANTITY_error
-*
+!:
 	lda basic_line_number+0
 	sta current_device_number
 got_devicenumber:
-	;; Now fetch the secondary address
+	// Now fetch the secondary address
 	lda #$00
 	sta current_secondary_address
 	jsr injest_comma
 	bcs got_secondaryaddress
 	jsr basic_parse_line_number
 	lda basic_line_number+1
-	bne +
+	bne !+
 	lda basic_line_number+0
 	sta current_secondary_address
 	jmp got_secondaryaddress
-*
+!:
-	;; Second parameter is above 255, this can't be a secondary address
+	// Second parameter is above 255, this can't be a secondary address
-	;; Use it as load address instead
+	// Use it as load address instead
-	;; XXX temporary syntax, it would be better to use something
+	// XXX temporary syntax, it would be better to use something
-	;; XXX like 'LOAD"FILE",8 TO 49152'
+	// XXX like 'LOAD"FILE",8 TO 49152'
 	ldx basic_line_number+0
 	ldy basic_line_number+1
 	bne got_loadaddress
 got_secondaryaddress:
-	ldx #<$0801
+	ldx #<$0801 // XXX use start text vector
 	ldy #>$0801
 got_loadaddress:
-	lda #$00 		; LOAD not verify
+	lda #$00 		// LOAD not verify
 	jsr via_ILOAD
-	bcc +
+	bcc !+
-	;; A = KERNAL error code, which also almost match
+	// A = KERNAL error code, which also almost match
-	;; basic ERROR codes, so we can just copy the
+	// basic ERROR codes, so we can just copy the
-	;; error code to X, decrement, and handle normally
+	// error code to X, decrement, and handle normally
 	tax
 	dex
 	jmp do_basic_error
-*
+!:
-	;; $YYXX is the last loaded address, so store it
+	// $YYXX is the last loaded address, so store it
 	stx basic_end_of_text_ptr+0
 	sty basic_end_of_text_ptr+1
-	;; Now relink the loaded program, as we cannot trust the line
+	// Now relink the loaded program, as we cannot trust the line
-	;; links supplied. For example, the VICE virtual drive emulation
+	// links supplied. For example, the VICE virtual drive emulation
-	;; always supplies $0101 as the address of the next line.
+	// always supplies $0101 as the address of the next line.
 	jsr basic_relink_program
-	;; After LOADing, we either start the program from the beginning,
+	// After LOADing, we either start the program from the beginning,
-	;; or go back to the READY prompt if LOAD was called from direct mode.
+	// or go back to the READY prompt if LOAD was called from direct mode.
-	;; Reset to start of program
+	// Reset to start of program
 	lda basic_start_of_text_ptr+0
 	sta basic_current_line_ptr+0
 	lda basic_start_of_text_ptr+1
 	sta basic_current_line_ptr+1
-	;; XXX - should run program if LOAD was used in program mode
+	// XXX - should run program if LOAD was used in program mode
 	jmp basic_main_loop
 basic_relink_program:
-	;; Start by getting pointer to the first line
+	// Start by getting pointer to the first line
 	lda basic_start_of_text_ptr+0
 	sta basic_current_line_ptr+0
 	lda basic_start_of_text_ptr+1
 	sta basic_current_line_ptr+1
 basic_relink_loop:	
-	;; Is the pointer to the end of the program
+	// Is the pointer to the end of the program
 	ldy #1
 	ldx #<basic_current_line_ptr+0
 	jsr peek_under_roms
 	cmp #$00
-	bne +
+	bne !+
-	;; End of program
+	// End of program
 	rts
-*
+!:
-	;; Now search forward to find the end of the line
+	// Now search forward to find the end of the line
-	;; Skip forward pointer and line number
+	// Skip forward pointer and line number
 	ldy #4
 end_of_line_search:
 	ldx #<basic_current_line_ptr+0
 	jsr peek_under_roms
 	cmp #$00
-	beq +
+	beq !+
-	;; Not yet end of line
+	// Not yet end of line
 	iny
 	bne end_of_line_search
-	;; line too long
+	// line too long
 	jmp do_STRING_TOO_LONG_error
-	*
+!:
-	;; Found end of line, so update pointer
+	// Found end of line, so update pointer
-	;; First, skip over the $00 char
+	// First, skip over the $00 char
 	iny
-	;; Now overwrite the pointer (carefully)
+	// Now overwrite the pointer (carefully)
-	;; 
+	// 
 	tya
 	clc
 	adc basic_current_line_ptr+0
@@ -2,18 +2,18 @@
 cmd_new:
 	jsr basic_do_new
-	;; NEW command terminates execution
+	// NEW command terminates execution
-	;; (Confirmed on a C64)
+	// (Confirmed on a C64)
 	jmp basic_main_loop
 cmd_clr:
 	jsr basic_do_clr
-	;; CLR command does not stop execution
+	// CLR command does not stop execution
-	;; (Cconfirmed on a c64)
+	// (Cconfirmed on a c64)
 	jmp basic_execute_statement
 basic_do_new:	
-	;; Setup pointers to memory storage
+	// Setup pointers to memory storage  XXX should depend on text start vector
 	lda #<$0801
 	sta basic_start_of_text_ptr+0
 	lda #>$0801
@@ -22,8 +22,8 @@ basic_do_new:
 	lda #<$0803
 	sta basic_start_of_vars_ptr+0
-	;; Zero line pointer
+	// Zero line pointer
-	;; XXX - We should also zero $0800, i.e., basic_start_of_text_ptr - 1
+	// XXX - We should also zero $0800, i.e., basic_start_of_text_ptr - 1
 	ldy #$00
 	tya
 	sta (basic_start_of_text_ptr),y
@@ -31,32 +31,32 @@ basic_do_new:
 	sta (basic_start_of_text_ptr),y
-	;; Get top of memory.
+	// Get top of memory.
-	;; If a cart is present, then it is $7FFF,
+	// If a cart is present, then it is $7FFF,
-	;; if not, then it is $F7FF, since we support having
+	// if not, then it is $F7FF, since we support having
-	;; programs and variables under ROM.
+	// programs and variables under ROM.
-	;; i.e., we support 56KB RAM for BASIC, keeping some space
+	// i.e., we support 56KB RAM for BASIC, keeping some space
-	;; free for some optimisation structures, e.g., FOR/NEXT loop
+	// free for some optimisation structures, e.g., FOR/NEXT loop
-	;; records (without them going on the stack), GOSUB stack
+	// records (without them going on the stack), GOSUB stack
-	;; (same story), expression value cache?
+	// (same story), expression value cache?
-	sec			; Read, not write value
+	sec			// Read, not write value
 	jsr JMEMTOP
 	cpx #$80
-	beq +
+	beq !+
 	lda #>$f7ff
-	.byte $2c
+	.byte $2C
-*	lda #>$7FFF
+!:	lda #>$7FFF
 	sta basic_top_of_memory_ptr+1
 	sta basic_start_of_strings_ptr+1
 	lda #<$f7ff
 	sta basic_top_of_memory_ptr+0
 	sta basic_start_of_strings_ptr+0	
-	;; FALL THROUGH
+	// FALL THROUGH
 basic_do_clr:
-	;; Clear variables, arrays and strings
+	// Clear variables, arrays and strings
 	lda basic_start_of_vars_ptr+0
 	sta basic_start_of_arrays_ptr+0
 	sta basic_start_of_free_space_ptr+0
@@ -65,5 +65,3 @@ basic_do_clr:
 	sta basic_start_of_free_space_ptr+1
 	rts
@@ -1,4 +1,4 @@
-	;; REM statement just skips to the next line
+// REM statement just skips to the next line
 cmd_rem:
 	jmp basic_end_of_line
@@ -1,21 +1,21 @@
 cmd_run:
-	;; RUN clears all variables
+	// RUN clears all variables
 	jsr basic_do_clr
 cmd_goto:	
-	;; Reset line pointer to first line of program.
+	// Reset line pointer to first line of program.
 	lda basic_start_of_text_ptr+0
 	sta basic_current_line_ptr+0
 	lda basic_start_of_text_ptr+1
 	sta basic_current_line_ptr+1
 	jsr basic_end_of_statement_check
-	bcs +
+	bcs !+
 	jsr basic_parse_line_number
 	jsr basic_find_line
-	bcc +
+	bcc !+
-	;; Line doesn't exist, so report error
+	// Line doesn't exist, so report error
 	jmp do_UNDEFD_STATEMENT_error
-*
+!:
-	;; Run it!
+	// Run it!
 	jmp basic_execute_from_current_line
@@ -1,23 +1,23 @@
 cmd_sys:
 	jsr basic_end_of_statement_check
-	bcc +
+	bcc !+
-	;; SYS requires an argument
+	// SYS requires an argument
-	jmp do_SYNTAX_ERROR
+	jmp do_SYNTAX_error
-*
+!:
 	jsr basic_parse_line_number
-	;; setup call
+	// setup call
-	lda #$4C ;JMP
+	lda #$4C // JMP opcode
 	sta USRPOK
 	lda basic_line_number+0
 	sta USRADD+0
 	lda basic_line_number+1
 	sta USRADD+1
-	;; Setup the register values
+	// Setup the register values
 	lda SPREG
 	pha
 	ldy SYREG
@@ -25,7 +25,7 @@ cmd_sys:
 	lda SAREG
 	plp
-	;; Call the routine.
+	// Call the routine.
 	jsr USRPOK
 	jmp basic_execute_statement
@@ -1,4 +1,4 @@
-	;; Default handler for all not-yet-implemented commands
+// Default handler for all not-yet-implemented commands
 cmd_for:
 cmd_next:
@@ -13,7 +13,7 @@ cmd_restore:
 cmd_gosub:
 cmd_return:
-	;; $90-$9F
+	// $90-$9F
 cmd_on:
 cmd_wait:
 cmd_save:
@@ -26,7 +26,7 @@ cmd_cont:
 cmd_cmd:
 cmd_open:
-	;; $A0-$AF
+	// $A0-$AF
 cmd_close:
 cmd_get:
 cmd_tab:
@@ -43,7 +43,7 @@ cmd_div:
 cmd_exponent:
 cmd_and:
-	;; $B0-$BF
+	// $B0-$BF
 cmd_or:
 cmd_greater:
 cmd_equal:
@@ -61,7 +61,7 @@ cmd_exp:
 cmd_cos:
 cmd_sin:
-	;; $C0-$CF
+	// $C0-$CF
 cmd_tan:
 cmd_atn:
 cmd_peek:
@@ -74,9 +74,9 @@ cmd_left:
 cmd_right:
 cmd_mid:
 cmd_go:
-	;; Undefined tokens
+ 	
 	// Undefined tokens
 cmd_unimplemented:
 	jmp do_NOT_IMPLEMENTED_error
@@ -1,48 +1,48 @@
-	;;  As many errors are triggered from many places in the BASIC
+//  As many errors are triggered from many places in the BASIC
-	;; interprettor, it is important to have an efficicent means of
+// interprettor, it is important to have an efficicent means of
-	;; calling them.
+// calling them.
-	;; LDX #$nn / jmp do_basic_error
+// LDX #$nn / jmp do_basic_error
-	;; is the simplest, but takes 5 bytes.
+// is the simplest, but takes 5 bytes.
-	;; Having a direct JMP address for each error is preferable, as
+// Having a direct JMP address for each error is preferable, as
-	;; it reduces the overhead to 3 bytes, but at the cost of having
+// it reduces the overhead to 3 bytes, but at the cost of having
-	;; a jump table of some sort. The .byte $2C method can be used
+// a jump table of some sort. The .byte $2C method can be used
-	;; to have a set of addresses that each execute a different
+// to have a set of addresses that each execute a different
-	;; LDX #$nn command, reducing the cost of the jump table to 3
+// LDX #$nn command, reducing the cost of the jump table to 3
-	;; bytes per error number.
+// bytes per error number.
-	;; But we can do better with a bit of scullduggery and carnal
+// But we can do better with a bit of scullduggery and carnal
-	;; knowledge of ZP usage.
+// knowledge of ZP usage.
-	;; The INC $nn opcode is $E6. ZP location $E6 is one of the screen
+// The INC $nn opcode is $E6. ZP location $E6 is one of the screen
-	;; link addresses.  In the original KERNAL, the lower bits of those
+// link addresses.  In the original KERNAL, the lower bits of those
-	;; addresses have meaning, but in our KERNAL, we ignore them, and just
+// addresses have meaning, but in our KERNAL, we ignore them, and just
-	;; have them all zeroes.  So.... We can have a sequence of $E6 bytes,
+// have them all zeroes.  So.... We can have a sequence of $E6 bytes,
-	;; and know exactly how many of them have been executed, by checking
+// and know exactly how many of them have been executed, by checking
-	;; the value of $E6.  Then all we need to worry about is if an odd
+// the value of $E6.  Then all we need to worry about is if an odd
-	;; number is required, then we have to have an exit that has a $E6
+// number is required, then we have to have an exit that has a $E6
-	;; opcode with some other address as target, but where the byte value
+// opcode with some other address as target, but where the byte value
-	;; of that argument can be safely executed as a CPU instruction.
+// of that argument can be safely executed as a CPU instruction.
-	;; NOP = $EA is the obvious choice, as if used as an argument to
+// NOP = $EA is the obvious choice, as if used as an argument to
-	;; $E6 will increment location $EA, which is another of the screen
+// $E6 will increment location $EA, which is another of the screen
-	;; link addresses.
+// link addresses.
-	;; This gives a total overhead of 18 bytes + 1 byte per error
+// This gives a total overhead of 18 bytes + 1 byte per error
-	;; message.  This compares favourably to the 3 bytes per error
+// message.  This compares favourably to the 3 bytes per error
-	;; message that the $2C method would result in.
+// message that the $2C method would result in.
 do_NOT_IMPLEMENTED_error:
 	.byte $E6
 do_MEMORY_CORRUPT_error:
 	.byte $E6
-	;; the message "BYTES FREE"
+	// the message "BYTES FREE"
 	.byte $E6
-	;; the word ERROR
+	// the word ERROR
 	.byte $E6
-	;; The word "SAVING"
+	// The word "SAVING"
 	.byte $E6
-	;; The word "VERIFYING"
+	// The word "VERIFYING"
 	.byte $E6
-	;; The word "LOADING"
+	// The word "LOADING"
 	.byte $E6
-	;; The word "READY."
+	// The word "READY."
 	.byte $E6	
 do_LOAD_error:
 	.byte $E6
@@ -103,69 +103,70 @@ do_FILE_OPEN_error:
 do_TO_MANY_FILES_error:
 	.byte $EA
-	;; Now get the error # and restore $E6 to its correct value
+	// Now get the error # and restore $E6 to its correct value
 	lda $E6
 	pha
 	and #$80
 	sta $E6
 	pla
-	;; $E6 has even part
+	// $E6 has even part
 	asl
 	ora $EA
 	and #$7f
 	tax
-	;; Restore $EA to correct value in case the NOP above is used
+	// Restore $EA to correct value in case the NOP above is used
-	;; as an argument to the preceeding INC $nn (opcode $E6).
+	// as an argument to the preceeding INC $nn (opcode $E6).
-	LDA $EA
+	lda $EA
 	and #$80
 	sta $EA
-	;; FALL THROUGH
+	// FALL THROUGH
-	;; Error # in X
+	// Error # in X
 do_basic_error:			
-	;; "?"
+	// "?"
 	txa
 	pha
 	lda #$0d
-	jsr $ffd2
+	jsr JCHROUT
 	lda #$3f
-	jsr $ffd2
+	jsr JCHROUT
 	pla
 	tax
-	;; Error message text
+	// Error message text
 	jsr print_packed_message
-	;; A space between error name and word error
+	// A space between error name and word error
 	lda #$20
 	jsr $ffd2
-	;; "ERROR"
+	// "ERROR"
 	ldx #33
 	jsr print_packed_message
 	lda basic_current_line_number+1
 	cmp #$ff
-	beq +
+	beq !+
-	;; We were in a program, so show IN <line>
+	// We were in a program, so show IN <line>
-	jsr printf
+	jsr printf // XXX don't use printf, use packed messages
-	.byte " IN ",0
+	.text " IN "
 	.byte 0
 	lda basic_current_line_number+1
 	ldx basic_current_line_number+0
 	jsr print_integer
-*
+!:
-	;; New lines
+	// New lines
 	lda #$0d
 	jsr $ffd2
 	lda #$00
 	jsr $ffd2
-	;; XXX - Restore stack depth first?
+	// XXX - Restore stack depth first?
 	jmp basic_main_loop
@@ -1,23 +1,23 @@
-	;; Multiply Floating Point Accumulator by 10
+// Multiply Floating Point Accumulator by 10
-	;; = 8x + 2x
+// = 8x + 2x
-	;; Implement by shifting MAC left one bit,
+// Implement by shifting MAC left one bit,
-	;; and then keeping that value to add on after
+// and then keeping that value to add on after
-	;; shifting two more bits left.
+// shifting two more bits left.
-	;; This should be done using basic_fac1_overflow to
+// This should be done using basic_fac1_overflow to
-	;; hold the overflow bits, so that the result can
+// hold the overflow bits, so that the result can
-	;; be exponent adjusted after, if required.
+// be exponent adjusted after, if required.
 fac1_mul10:
 	lda #$00
 	sta basic_fac1_overflow
-	;; Multiply mantissa by 2
+	// Multiply mantissa by 2
 	jsr fac1_mantissa_mul2
-	;; copy down to BASIC numeric work area at $57
+	// copy down to BASIC numeric work area at $57
-	;; (basic_numeric_work_area)
+	// (basic_numeric_work_area)
-	;; (We copy all 7 bytes off the FAC1, so that we have
+	// (We copy all 7 bytes off the FAC1, so that we have
-	;; the overflow bits, and the copy is as small as possible)
+	// the overflow bits, and the copy is as small as possible)
 	ldx #7
 f1m10_l1:	
 	lda basic_fac1_mantissa,x
@@ -25,11 +25,11 @@ f1m10_l1:
 	dex
 	bpl f1m10_l1
-	;; Multiply mantissa by 4, so it is now 8x original
+	// Multiply mantissa by 4, so it is now 8x original
 	jsr fac1_mantissa_mul2
 	jsr fac1_mantissa_mul2
-	;; Now add stored value of 2x to it, to get the total x10
+	// Now add stored value of 2x to it, to get the total x10
 	ldy #3
 	ldx #0
 	clc
@@ -44,22 +44,22 @@ f1m10_l2:
 	adc basic_numeric_work_area+7
 	sta basic_fac1_overflow
-	;; Now shift right and increase exponent until overflow
+	// Now shift right and increase exponent until overflow
-	;; bits = $00
+	// bits = $00
 f1m10_l3:
 	lda basic_fac1_overflow
-	bne +
+	bne !+
-	;; All done, return
+	// All done, return
 	clc
 	rts
-*
+!:
-	;; Divide mantissa by two, and increment exponent
+	// Divide mantissa by two, and increment exponent
 	jsr fac1_mantissa_div2
 	inc basic_fac1_exponent
 	lda basic_fac1_exponent
 	bpl f1m10_l3
-	;; Exponent has bit 7 set, so has wrapped.
+	// Exponent has bit 7 set, so has wrapped.
-	;; = OVERFLOW ERROR
+	// = OVERFLOW ERROR
 	jmp do_OVERFLOW_error
 fac1_mantissa_mul2:	
@@ -67,8 +67,8 @@ fac1_mantissa_mul2:
 	ldx #0
 	clc
 f1m1_l1:
-	;; Multiply mantissa by 2, and store overflow
+	// Multiply mantissa by 2, and store overflow
-	;; in basic_fac1_bits
+	// in basic_fac1_bits
 	lda basic_fac1_mantissa,x
 	rol
 	sta basic_fac1_mantissa,x
@@ -82,7 +82,7 @@ f1m1_l1:
 	rts
 fac1_mantissa_div2:
-	;; Divide mantissa by 2, including using overflow bits
+	// Divide mantissa by 2, including using overflow bits
 	clc
 	lda basic_fac1_overflow
 	ror
@@ -1,15 +1,15 @@
-;; Consummes a comma in a BASIC code, C set for no coma found
+// Consummes a comma in a BASIC code, C set for no coma found
 injest_comma:
 	jsr basic_fetch_and_consume_character
-	cmp #$2C ; comma character
+	cmp #$2C // comma character
 	beq injest_comma_found
-	cmp #$20
+	cmp #$20 // space, can always be skipped
-	beq injest_comma ; space, can always be skipped
+	beq injest_comma
-	;; not found
+	// not found
 	jsr basic_unconsume_character
 	sec
 	rts
@@ -17,4 +17,3 @@ injest_comma:
 injest_comma_found:
 	clc
 	rts
@@ -1,37 +1,37 @@
-	;; Parse a number from the input buffer at (basic_current_statement_ptr)
+// Parse a number from the input buffer at (basic_current_statement_ptr)
-	;; Result is put into FAC1.
+// Result is put into FAC1.
-	;; basic_current_statement_ptr is updated with first position after the number.
+// basic_current_statement_ptr is updated with first position after the number.
-	;; XXX - Remember decimal position and exponent, and apply them
+// XXX - Remember decimal position and exponent, and apply them
-	;; after to produce normalised floating point number.
+// after to produce normalised floating point number.
-	;; XXX - Doesn't use routines to access memory under ROMs etc.
+// XXX - Doesn't use routines to access memory under ROMs etc.
-	;; This is important, because this routine operates on numbers in BASIC text.
+// This is important, because this routine operates on numbers in BASIC text.
 ij_not_a_digit:
-	;; XXX check for "." or "E"
+	// XXX check for "." or "E"
-	;; Other chars terminate the accumulation.
+	// Other chars terminate the accumulation.
-	;; Look for exponentiation marker
+	// Look for exponentiation marker
-	;; XXX - Implement me!
+	// XXX - Implement me!
-	;; Probably should have a flag so that we know if we are accumulating
+	// Probably should have a flag so that we know if we are accumulating
-	;; exponent or mantissa digits
+	// exponent or mantissa digits
-	;; Look for decimal point
+	// Look for decimal point
 	cmp #$2e
 	bne ij_not_decimal
 	lda tokenise_work4
 	cmp #$ff
 	beq ij_found_decimal
-	;; More than one decimal point in a number means we have reached the end of the number
+	// More than one decimal point in a number means we have reached the end of the number
 	clc
 	rts
 ij_found_decimal:
-	;; Found decimal.
+	// Found decimal.
-	;; Thus start counting digits after the decimal, so that we
+	// Thus start counting digits after the decimal, so that we
-	;; can do the necessary number of divide by 10s on the final
+	// can do the necessary number of divide by 10s on the final
-	;; number.
+	// number.
 	lda #$00
 	sta tokenise_work4
@@ -39,31 +39,30 @@ ij_found_decimal:
 ij_not_decimal:
-	
+	clc
-	CLC
+	rts
 	RTS
 injest_number:
-	;; Clear FAC1
+	// Clear FAC1
 	jsr erase_fac1
-	;; Clear decimal position flag
+	// Clear decimal position flag
 	lda #$ff
 	sta tokenise_work4
-	;; Check if leading char is a - sign
+	// Check if leading char is a - sign
-	;; Note: the - will have been tokenised to $AB
+	// Note: the - will have been tokenised to $AB
-	;; XXX - implement
+	// XXX - implement
 	ldy #$00
 	lda (basic_current_statement_ptr),y
 	cmp #$AB
 	bne ij_not_minus
-	;; Set sign to negative
+	// Set sign to negative
 	lda #$ff
 	sta basic_fac1_sign
-	;; Skip over the minus sign
+	// Skip over the minus sign
 	jsr basic_consume_character
 ij_not_minus:	
@@ -77,43 +76,43 @@ ij_loop1:
 	cmp #$3a
 	bcs ij_not_a_digit
-	;; It is a digit
+	// It is a digit
-	;; Only add digit if we have not overflowed the accuracy of
+	// Only add digit if we have not overflowed the accuracy of
-	;; the mantissa
+	// the mantissa
 	lda basic_fac1_exponent
 	beq ij_accept_precision
-	;; We have an extra digit after saturating our precision.
+	// We have an extra digit after saturating our precision.
-	;; Thus we should ignore the digit, and just multiply the FAC
+	// Thus we should ignore the digit, and just multiply the FAC
-	;; by 10, but only if we have not seen a decimal point.
+	// by 10, but only if we have not seen a decimal point.
-	;; If we have seen a decimal point, then we can completely ignore
+	// If we have seen a decimal point, then we can completely ignore
-	;; the digit, as it is contributing not recordable information
+	// the digit, as it is contributing not recordable information
 	lda tokenise_work4
 	cmp #$ff
 	bne ij_seen_decimal_point
 	jsr fac1_mul10
-	;; Fall through
+	// Fall through
 ij_seen_decimal_point:
 	jmp ij_consider_next_digit
 ij_accept_precision:
-	;; We can accept more precision, so multiply the mantissa by 10, so that
+	// We can accept more precision, so multiply the mantissa by 10, so that
-	;; we can add the new digit in
+	// we can add the new digit in
 	jsr fac1_mul10
 	lda basic_fac1_exponent
 	bne ij_consider_next_digit
-	;; Get digit
+	// Get digit
 	ldy #$00
 	lda (basic_current_statement_ptr),y
 	sec
 	sbc #$30
-	;; Add to FAC1 mantissa
+	// Add to FAC1 mantissa
 	clc
 	adc basic_fac1_mantissa+0
 	sta basic_fac1_mantissa+0
@@ -127,16 +126,16 @@ ij_loop2:
 	dey
 	bne ij_loop2
-	bcc +
+	bcc !+
-	;; Carry set, so we have overflowed.
+	// Carry set, so we have overflowed.
-	;; We should shift everything right one digit, and increase
+	// We should shift everything right one digit, and increase
-	;; the exponent by one.  The non-zero exponent tells us that we
+	// the exponent by one.  The non-zero exponent tells us that we
-	;; can't fit any more precision in.
+	// can't fit any more precision in.
 	jsr fac1_mantissa_div2
-*
+!:
 ij_consider_next_digit:	
-	;; Consider next digit
+	// Consider next digit
 	jsr basic_consume_character
 	jmp ij_loop1
@@ -146,10 +145,10 @@ ij_consider_next_digit:
 erase_fac1:	
 	lda #$00
 	ldx #8
-*
+!:
 	sta basic_fac1_exponent,x
 	dex
-	bpl -
+	bpl !-
 	sta basic_fac1_mantissa_lob
 	rts
@@ -1,76 +1,77 @@
-	;; Pack a word using the simple compression scheme.
+// Pack a word using the simple compression scheme.
-	;; This has to be the same implementation as in compress_text.c
+// This has to be the same implementation as in compress_text.c
-	;; because we compress input lines of BASIC to do the tokenisation.
+// because we compress input lines of BASIC to do the tokenisation.
-	;; This allows us to search through the compressed tokens directly
+// This allows us to search through the compressed tokens directly
-	;; using the compressed fragment of BASIC, and thus work out the
+// using the compressed fragment of BASIC, and thus work out the
-	;; token for a given piece of string.
+// token for a given piece of string.
-	;; This also helps ensure that we have an implementation that is totally
+// This also helps ensure that we have an implementation that is totally
-	;; different to that of the original C64 BASIC, as well as likely
+// different to that of the original C64 BASIC, as well as likely
-	;; saving a bit of space in the ROM, especially once we start implementing
+// saving a bit of space in the ROM, especially once we start implementing
-	;; larger keyword vocabs for BASIC 7 or BASIC 10 compatibility, since the
+// larger keyword vocabs for BASIC 7 or BASIC 10 compatibility, since the
-	;; compression and decompression machinery is of fixed size.
+// compression and decompression machinery is of fixed size.
 pack_word:
-	;; Inputs:
+	// Inputs:
-	;; X = offset of string to pack. Address is $0200 + X
+	// X = offset of string to pack. Address is $0200 + X
-	;; tokenise_work1 = number of bytes to pack
+	// tokenise_work1 = number of bytes to pack
-	;; tokenise_work2 = packed length of string
+	// tokenise_work2 = packed length of string
-	;; Outputs:
+	// Outputs:
-	;; Output is written to $0100 (bottom of stack).
+	// Output is written to $0100 (bottom of stack).
-	;; Memory modified:
+	// Memory modified:
-	;; tokenise_work4 = temporary storage
+	// tokenise_work4 = temporary storage
-	;; tokenise_work3 = flag for whether we have a nybl prepared or not.
+	// tokenise_work3 = flag for whether we have a nybl prepared or not.
-	;; (This can also be checked on exit, to know whether the last byte
+	// (This can also be checked on exit, to know whether the last byte
-	;; is incomplete, which is important for searching for abbreviated
+	// is incomplete, which is important for searching for abbreviated
-	;; key words.)
+	// key words.)
-	;; Make sure we have a sane request
+	// Make sure we have a sane request
 	lda tokenise_work1
-	bne +
+	bne !+
 	sec
 	rts
-*	
+!:
-	;; Initialise internal variables
+	// Initialise internal variables
 	lda #$00
 	sta tokenise_work2
 	sta tokenise_work3
 pack_char_loop:
-	;; Get the next char
+	// Get the next char
 	lda $0200,x
-	;; Work out what type of character we have, and thus
+	// Work out what type of character we have, and thus
-	;; how we need to pack it.
+	// how we need to pack it.
 	jsr get_packed_char_index
 	cmp #$00
 	bne not_exception_char
-	;; Char is an exception char.
+	// Char is an exception char.
-	;; We need to either finish the previous byte with $xF,
+	// We need to either finish the previous byte with $xF,
-	;; Or if there is no existing nybl, then we need to output
+	// Or if there is no existing nybl, then we need to output
-	;; either $FE or $FF, depending on whether this is the last
+	// either $FE or $FF, depending on whether this is the last
-	;; byte or not
+	// byte or not
 	lda tokenise_work3
 	bne have_nybl_before_exception_char
-	;; No nybl exists before the exception char, so prefix with $FE or $FF
+	// No nybl exists before the exception char, so prefix with $FE or $FF
-	;; based on whether we are at the end of the input string or not
+	// based on whether we are at the end of the input string or not
 	inx
 	lda tokenise_work1
 	cmp #$01
 	beq at_end
 	lda #$FF
 	.byte $2C
-at_end:	LDA #$FE
+at_end:
 	lda #$FE
 	dex
 	jsr write_unpacked_char
-	;; Fall through
+	// Fall through
 output_exception_byte:	
 	lda $0200,x
@@ -78,18 +79,18 @@ output_exception_byte:
 	jmp consider_next_char
 have_nybl_before_exception_char:
-	;; Or existing byte with #$0F, and clear nybl flag
+	// Or existing byte with #$0F, and clear nybl flag
 	ldy tokenise_work2
 	lda $0100,y
 	ora #$0f
 	sta $0100,y
 	inc tokenise_work2
-	;; FALL THROUGH
+	// FALL THROUGH
 write_literal_and_terminate_if_required:	
-	;; Clear have nybl flag
+	// Clear have nybl flag
 	lda #$00
 	sta tokenise_work3
@@ -99,19 +100,19 @@ write_literal_and_terminate_if_required:
 	jmp end_string_if_required
 end_string_if_required:
-	;; Check if X points to last char of string to be packed
+	// Check if X points to last char of string to be packed
 	inx
 	lda tokenise_work1
 	cmp #$01
-	beq +
+	beq !+
 	dex
 	jmp consider_next_char
-*
+!:
 	dex
-	;;  Fall through
+	//  Fall through
 end_string:
-	;; Write end of string sequence if required
+	// Write end of string sequence if required
 	lda #$00
 	jsr write_unpacked_char
 	rts
@@ -124,53 +125,53 @@ write_unpacked_char:
 	rts
 not_exception_char:
-	;; It wasn't an exception char, so write the symbol out
+	// It wasn't an exception char, so write the symbol out
 	cmp #$10
 	bcs whole_byte_symbol
-	;; Nybl encoded value: Put in upper half or lower half of a byte?
+	// Nybl encoded value: Put in upper half or lower half of a byte?
 	ldy tokenise_work3
 	bne store_low_nybl
-	;; Store in high nybl -- so shift it into the hi nybl
+	// Store in high nybl -- so shift it into the hi nybl
 	asl
 	asl
 	asl
 	asl
 	ldy tokenise_work2
 	sta $0100,y
-	bne stored_nybl 	; Must be taken, as A cannot be $00
+	bne stored_nybl 	// Must be taken, as A cannot be $00
 store_low_nybl:
-	;; Low nybl gets added to high nybl already stored in the byte
+	// Low nybl gets added to high nybl already stored in the byte
 	ldy tokenise_work2
 	ora $0100,y
 	sta $0100,y
 stored_nybl:	
-	;; Now toggle the nybl flag
+	// Now toggle the nybl flag
 	lda tokenise_work3
 	eor #$ff
 	sta tokenise_work3
-	;; And advance the offset if we filled this byte up
+	// And advance the offset if we filled this byte up
-	bne consider_next_char 	; Taken if byte has a nybl free, i.e., don't advance pointer while half byte remains free
+	bne consider_next_char 	// Taken if byte has a nybl free, i.e., don't advance pointer while half byte remains free
-	;; Count the filled up byte
+	// Count the filled up byte
 	inc tokenise_work2
-	;; Add termination byte if required
+	// Add termination byte if required
-	;; (This re-writes the same byte again, which we don't care about)
+	// (This re-writes the same byte again, which we don't care about)
 	jmp end_string_if_required
 whole_byte_symbol:
-	;; It's a $Fx symbol.
+	// It's a $Fx symbol.
-	;; But if we have a nybl to flush, then we handle it like
+	// But if we have a nybl to flush, then we handle it like
-	;; a full exception character
+	// a full exception character
 	ldy tokenise_work3
 	beq nothing_to_flush
-	;; Set low nybl to $F to mark next byte as literal
+	// Set low nybl to $F to mark next byte as literal
 	ldy tokenise_work2
 	lda $0100,y
 	ora #$0f
@@ -180,30 +181,30 @@ whole_byte_symbol:
 	jmp write_literal_and_terminate_if_required
 nothing_to_flush:
-	;; Write the symbol as it is, or the literal
+	// Write the symbol as it is, or the literal
-	;; if it has been passed to us via fall-through
+	// if it has been passed to us via fall-through
 	jsr write_unpacked_char
 	jmp end_string_if_required
 consider_next_char:	
-	;; Pack next char
+	// Pack next char
 	inx 
 	dec tokenise_work1
-	beq +
+	beq !+
 	jmp pack_char_loop
-*
+!:
-	;; Add 1 to length if nybl waiting to be flushed
+	// Add 1 to length if nybl waiting to be flushed
-	;; (but leave flag set so the caller knows if the
+	// (but leave flag set so the caller knows if the
-	;; bottom nybl might be different if the string were
+	// bottom nybl might be different if the string were
-	;; longer).
+	// longer).
 	lda tokenise_work3
-	beq +
+	beq !+
 	inc tokenise_work2
 	rts
-*	
+!:
-	;; Last byte was full, so we need at $00 on the end
+	// Last byte was full, so we need at $00 on the end
-	;; (unless a $FE token was written 2 bytes ago)
+	// (unless a $FE token was written 2 bytes ago)
 	ldy tokenise_work2
 	iny
 	lda #$00
@@ -213,21 +214,21 @@ consider_next_char:
 	rts
 get_packed_char_index:
-	;; Find char in A in the packed char list, and return
+	// Find char in A in the packed char list, and return
-	;; $1 - $E, $F1 - $FD if the charactar is abbreviable,
+	// $1 - $E, $F1 - $FD if the charactar is abbreviable,
-	;; or else return $00 if the character has to be stored literally.
+	// or else return $00 if the character has to be stored literally.
-	;; Y register and A are modified, as are processor flags.
+	// Y register and A are modified, as are processor flags.
 	ldy #$00
 find_char_loop:	
 	cmp packed_message_chars,y
 	bne not_a_match
 enumerate:	
-	;; Is it a nybl abbreviable char?
+	// Is it a nybl abbreviable char?
 	cpy #14
 	bcs not_nybl_char
-	;; Yes, so add 1 and return it
+	// Yes, so add 1 and return it
 	iny
 	tya
 	rts
@@ -235,9 +236,9 @@ enumerate:
 not_nybl_char:
 	cpy #27
 	bcs not_a_match
-	;; It's a $Fx character.
+	// It's a $Fx character.
-	;; Since the lowest index is $E, and it should be encoded as $F1
+	// Since the lowest index is $E, and it should be encoded as $F1
-	;; we need to add $E3
+	// we need to add $E3
 	tya
 	clc
 	adc #$E3
@@ -245,10 +246,10 @@ not_nybl_char:
 not_a_match:
 	iny
-	;; Loop until we find it, or we discover it isn't
+	// Loop until we find it, or we discover it isn't
-	;; a character with a special encoding
+	// a character with a special encoding
 	cpy #27
 	bne find_char_loop
-	;; Not a char that we can pack, so return 0
+	// Not a char that we can pack, so return 0
 	lda #$00
 	rts
@@ -1,5 +1,5 @@
-	;; Return C=1 if a pointer in BASIC memory space is NULL, else C=0
+// Return C=1 if a pointer in BASIC memory space is NULL, else C=0
-	;; X = ZP pointer to check
+// X = ZP pointer to check
 peek_pointer_null_check:
 	ldy #$00
@@ -11,7 +11,7 @@ peek_pointer_null_check:
 	cmp #$00
 	bne ptr_not_null
-	;; Pointer is NULL
+	// Pointer is NULL
 	clc
 	rts
 ptr_not_null:
@@ -1,26 +1,27 @@
-	;; Works similar to $BDCD in original C64 BASIC
+// Works similar to $BDCD in original C64 BASIC
-	;; XXX Should eventually get replaced by a more flexible and optimal routine.
+// XXX Should eventually get replaced by a more flexible and optimal routine.
-	;; Temp result gets written to $0100-$0104
+// Temp result gets written to $0100-$0104
 print_integer:
 	pha
 	txa
 	pha
-	;; Clear temporary output
+	// Clear temporary output
 	lda #$00
 	ldy #5
-*	sta $0100,y
+!:	sta $0100,y
 	dey
-	bpl -
+	bpl !-
 	pla
-	ldy #23 		; 8 x 3 - 1 = offset of last digit of 128
+	ldy #23 		// 8 x 3 - 1 = offset of last digit of 128
 lo_loop:	
 	cmp #$7f
 	bcc bit_clear
-	;; Bit set, so add the digits
+	// Bit set, so add the digits
 	pha
 	ldx #2
 	clc
@@ -45,16 +46,16 @@ next_lo_bit:
 	bcc lo_loop	
-	;; Now do the same for upper byte
+	// Now do the same for upper byte
 	pla
-	ldy #39 		; 8 x 5 - 1 = offset of last digit of 32768
+	ldy #39 		// 8 x 5 - 1 = offset of last digit of 32768
 hi_loop:	
 	cmp #$7f
 	bcc bit_clear_hi
-	;; Bit set, so add the digits
+	// Bit set, so add the digits
 	pha
 	ldx #4
 	clc
@@ -82,12 +83,12 @@ next_hi_bit:
 fix_carry:
-	;; Deal with any carries
+	// Deal with any carries
 	ldx #3
 carry_fix_loop:
 	lda $0101,x
 	cmp #10
-	bcc +
+	bcc !+
 	inc $0100,x
 	sec
 	sbc #10
@@ -95,30 +96,30 @@ carry_fix_loop:
 	jmp carry_fix_loop	
-*	dex	
+!:	dex	
 	bpl carry_fix_loop
 post_carry:
-	;; Got digits.
+	// Got digits.
-	;; Skip leading zeros, and print the resulting number
+	// Skip leading zeros, and print the resulting number
-	;; Skip leading zeros
+	// Skip leading zeros
 	ldy #0
-*	lda $0100,y
+!:	lda $0100,y
 	bne found_start_of_number
 	iny
 	cpy #4
-	bne -
+	bne !-
 found_start_of_number:
-	;; Print digits
+	// Print digits
-*	lda $0100,y
+!:	lda $0100,y
 	ora #$30
 	jsr JCHROUT
 	iny
 	cpy #5
-	bne -
+	bne !-
 	rts
@@ -1,16 +1,17 @@
-	;; This routine prints messages that have been packed
+// This routine prints messages that have been packed
-	;; using the make_error_tables program.
+// using the make_error_tables program.
-	;; The general idea is to save space in the ROM.
+// The general idea is to save space in the ROM.
 // The output of make_error_tables is written to packed_messages.s, and
 // contains the following:
 // 
 // packed_message_words - List of nybl packed words.
 // packed_message_tokens - List of tokens that get joined to make messages
 // packed_message_chars - List of characters in messages sorted by frequency.
 	;; The output of make_error_tables is written to packed_messages.s, and
 	;; contains the following:
 	;; 
 	;; packed_message_words - List of nybl packed words.
 	;; packed_message_tokens - List of tokens that get joined to make messages
 	;; packed_message_chars - List of characters in messages sorted by frequency.
 print_packed_message:
-	;; X = message number
+	// .X = message number
 	lda #$ff
 	ldy #$ff
@@ -20,22 +21,22 @@ packed_message_search:
 	beq found_message_in_token_stream
 	lda packed_message_tokens,y
 	cmp #$ff
-	bne +
+	bne !+
 	dex
-*
+!:
 	cpy #$ff
 	bne packed_message_search
-	;; Could not find message
+	// Could not find message
 	sec
 	rts
 found_message_in_token_stream:
-	;; Now print each word in the message
+	// Now print each word in the message
 	tya
 	pha
 	lda packed_message_tokens,y
 	cmp #$ff
-	beq +
+	beq !+
 	jsr print_packed_word
 	lda #$20
 	jsr JCHROUT
@@ -43,50 +44,50 @@ found_message_in_token_stream:
 	tay
 	iny
 	bne found_message_in_token_stream
-*
+!:
 	pla
-	;; Rub out space at the end
+	// Rub out space at the end
 	lda #$14
 	jsr JCHROUT
 	rts
 print_packed_word:
-	;; A = the word to print
+	// A = the word to print
 	tax
-	;; Setup pointer to packed words
+	// Setup pointer to packed words
 	lda #<packed_message_words
 	sta temp_string_ptr+0
 	lda #>packed_message_words
 	sta temp_string_ptr+1
-	;; Find the word in the list
+	// Find the word in the list
 	ldy #$ff
 packed_word_search:
 	iny
 	cpx #$00
 	beq found_packed_word
-	;;  $x0 is an end of work marker
+	//  $x0 is an end of work marker
 	lda (temp_string_ptr),y
 	and #$0f
 	cmp #$00
-	bne +
+	bne !+
 	dex
-*
+!:
-	;; $FE $xx is an end of work marker
+	// $FE $xx is an end of work marker
 	lda (temp_string_ptr),y
 	cmp #$fe
-	bne +
+	bne !+
 	dex 
-	iny 			; skip next byte
+	iny 			// skip next byte
-*
+!:
 	cmp #$ff
-	bne +
+	bne !+
-	iny			; skip next byte
+	iny			// skip next byte
-*
+!:
-	;; Advance to next page if required
+	// Advance to next page if required
 	cpy #$ff
 	bne packed_word_search
 	inc temp_string_ptr+1
@@ -94,8 +95,8 @@ packed_word_search:
 found_packed_word:
-	;; Get pointer to start of packed word
+	// Get pointer to start of packed word
-	;; Make sure we don't wrap on a page boundary
+	// Make sure we don't wrap on a page boundary
 	tya
 	clc
 	adc temp_string_ptr+0
@@ -108,10 +109,10 @@ print_packed_string:
 	ldy #$ff
 next_packed_word_char:
-	;; Y = offset into packed word data - 1
+	// .Y = offset into packed word data - 1
 	iny
-	;; Check for end of word
+	// Check for end of word
 	lda (temp_string_ptr),y
 	cmp #$00
 	beq end_of_packed_word
@@ -122,31 +123,31 @@ next_packed_word_char:
 	and #$f0
 	beq end_of_packed_word	
-	;; Check if it is an uncommon char
+	// Check if it is an uncommon char
 	lda (temp_string_ptr),y
 	and #$f0
 	cmp #$f0
 	beq is_uncommon_char
-	;; Is not an uncommon char, so get char of upper nybl
+	// Is not an uncommon char, so get char of upper nybl
 	lda (temp_string_ptr),y
-	;; Put high nybl into low bits of X
+	// Put high nybl into low bits of X
 	lsr
 	lsr
 	lsr
 	lsr
 	tax
-	;; Save Y so it doesn't get clobbered by CHROUT
+	// Save Y so it doesn't get clobbered by CHROUT
 	tya
 	pha
-	;; X=1-14 = first 14 chars, so subtract one
+	// X=1-14 = first 14 chars, so subtract one
 	lda packed_message_chars-1,x
 	jsr JCHROUT
-	;; See if there is a char in the low nybl to print
+	// See if there is a char in the low nybl to print
 	pla
 	tay
 	lda (temp_string_ptr),y
@@ -156,31 +157,31 @@ next_packed_word_char:
 	beq no_lo_nybl_char
 has_lo_nybl_char:
-	;; We need to print the low nybl char as well
+	// We need to print the low nybl char as well
 	tax
 	tya
 	pha
-	;; Skip lower nybls of $F or $0 in nybl packed
+	// Skip lower nybls of $F or $0 in nybl packed
-	;; bytes, as these do not encode characters
+	// bytes, as these do not encode characters
 	cpx #$f
-	beq +
+	beq !+
 has_nybl:
 	cpx #0
-	beq +
+	beq !+
-	;; X=1-14 = first 14 chars, so subtract one
+	// X=1-14 = first 14 chars, so subtract one
 	lda packed_message_chars-1,x
 	jsr JCHROUT
-*
+!:
 	pla
 	tay
-	;; FALL THROUGH
+	// FALLTHROUGH
 no_lo_nybl_char:
-	;; If current byte has $0F in low nybl, then the next
+	// If current byte has $0F in low nybl, then the next
-	;; byte is a whole byte.
+	// byte is a whole byte.
 	lda (temp_string_ptr),y
 	and #$0f
 	cmp #$0f
@@ -190,7 +191,7 @@ ready_for_next_char:
 	cpy #$ff
 	bne next_packed_word_char
 end_of_packed_word:
-	;; Hit end of packed data
+	// Hit end of packed data
 	rts
 last_literal:
@@ -202,7 +203,7 @@ next_is_literal_char:
 	jmp ready_for_next_char
 unpack_literal_char:
-	;; Output the literal char, and ready for next char
+	// Output the literal char, and ready for next char
 	iny
 	tya
 	pha
@@ -213,14 +214,14 @@ unpack_literal_char:
 	rts
 is_uncommon_char:
-	;; Lower nybl has offset into low-frequency part of the table
+	// Lower nybl has offset into low-frequency part of the table
 	lda (temp_string_ptr),y
 	and #$0f
 	clc
 	adc #14
-	;; We need to print the low nybl char as well
+	// We need to print the low nybl char as well
 	tax
 	tya
 	pha
@@ -1,17 +1,17 @@
-	;; printf()-like routine for simplifying debugging
+// printf()-like routine for simplifying debugging
-	;; Prints the literal zero-terminated string that follows,
+// Prints the literal zero-terminated string that follows,
-	;; which may also include special tokens that allow
+// which may also include special tokens that allow
-	;; printing of hex byte and word values stored at the indicated
+// printing of hex byte and word values stored at the indicated
-	;; addresses.
+// addresses.
-	;; .byte 1,$byte = display byte as hex
+// .byte 1,$byte = display byte as hex
-	;; .byte 2,$low,$hi = display word as hex
+// .byte 2,$low,$hi = display word as hex
-	;; .byte $f0+n,$low,$hi = display byte at $hi$lo+n as hex
+// .byte $f0+n,$low,$hi = display byte at $hi$lo+n as hex
 printf:
-	;; Temporary storage is between end of screen at $0400
+	// Temporary storage is between end of screen at $0400
-	;; and the sprite pointers at $7f8
+	// and the sprite pointers at $7f8
 	sta $7f0
 	stx $7f1
 	sty $7f2
@@ -19,14 +19,14 @@ printf:
 	pla
 	sta $7f3
-	;; Set up read routine
+	// Set up read routine
-	lda #$ad 		; LDA $nnnn
+	lda #$ad 		// LDA $nnnn
 	sta $7f4
 	lda #$60
-	sta $7f7		; RTS
+	sta $7f7		// RTS
-	;; Get PC of caller from the stack, so that
+	// Get PC of caller from the stack, so that
-	;; we can parse through it
+	// we can parse through it
 	pla
 	clc
 	adc #$01
@@ -39,8 +39,8 @@ printf_loop:
 	jsr $7f4
 	cmp #$00
 	bne printf_continues
-	;; Put return address on stack and restore
+	// Put return address on stack and restore
-	;; registers
+	// registers
 	lda $7f6
 	pha
 	lda $7f5
@@ -56,33 +56,33 @@ printf_loop:
 printf_continues:
 	cmp #$01
 	bne not_hexbyte
-	;; Print a hex byte
+	// Print a hex byte
-	;; Skip the token
+	// Skip the token
 	jsr printf_advance
-	;; Read the low byte
+	// Read the low byte
 	jsr $7f4
-	;; Print as hex
+	// Print as hex
 	jsr printf_printhexbyte
 	jmp printf_nextchar
 not_hexbyte:
 	cmp #$02
 	bne not_hexword
-	;; Print a hex word
+	// Print a hex word
-	;; Skip the token
+	// Skip the token
 	jsr printf_advance
 	jsr printf_advance
-	;; Read the high byte
+	// Read the high byte
 	jsr $7f4
-	;; Print as hex
+	// Print as hex
 	jsr printf_printhexbyte
-	;; Skip the token
+	// Skip the token
 	jsr printf_retreat
-	;; Read the low byte
+	// Read the low byte
 	jsr $7f4
-	;; Print as hex
+	// Print as hex
 	jsr printf_printhexbyte
 	jsr printf_advance
 	jmp printf_nextchar
@@ -91,11 +91,11 @@ not_hexword:
 	cmp #$f0
 	bcc not_pointer
-	;; Treat two-byte arg as base address
+	// Treat two-byte arg as base address
-	;; and lower 4 bits of token as offset from
+	// and lower 4 bits of token as offset from
-	;; that location.
+	// that location.
-	;; Get offset
+	// Get offset
 	and #$0f
 	tay
@@ -111,7 +111,7 @@ not_hexword:
 	jmp printf_nextchar
 not_pointer:	
-	;; Print character
+	// Print character
 	jsr JCHROUT
 printf_nextchar:
@@ -120,15 +120,15 @@ printf_nextchar:
 	jmp printf_loop
 printf_advance:
-	;; Advance pointer to next character
+	// Advance pointer to next character
 	inc $7f5
-	bne +
+	bne !+
 	inc $7f6
-	*
+!:
 	rts
 printf_retreat:
-	;; Retreat pointer to previous char
+	// Retreat pointer to previous char
 	lda $7f5
 	sec
 	sbc #1
@@ -139,7 +139,7 @@ printf_retreat:
 	rts
 printf_printhexbyte:
-	;; Print the hex value in .A as two digits, idea by Haubitze
+	// Print the hex value in .A as two digits, idea by Haubitze
 	sed
 	pha
 	lsr
@@ -1,6 +1,6 @@
 ready_message:
-	;; See src/make_error_tables.c for packed message handling
+	// See src/make_error_tables.c for packed message handling
-	;; information.
+	// information.
 	ldx #29
 	jmp print_packed_message
@@ -1,19 +1,19 @@
 select_device:
-	;; Take last device number, make sure it's a drive - 8 or above. Above 30,
+	// Take last device number, make sure it's a drive - 8 or above. Above 30,
-	;; although illegal for IEC we also consider a drive, as they exists
+	// although illegal for IEC we also consider a drive, as they exists
-	;; drivers assigning these numbers to CBM-DOS capable devices - like some
+	// drivers assigning these numbers to CBM-DOS capable devices - like some
-	;; IEEE-488 carts.
+	// IEEE-488 carts.
-	;;
+	//
-	;; If current device is not a drive, set device to 8 (first drive number)
+	// If current device is not a drive, set device to 8 (first drive number)
-	;; Device number is left in X, for SETFLS Kernal routine
+	// Device number is left in X, for SETFLS Kernal routine
-	;; Note: if tape support is introduced here, make sure DOS wedge won't get broken
+	// Note: if tape support is introduced here, make sure DOS wedge won't get broken
 	ldx current_device_number
 	cpx #$08
-	bcs +
+	bcs !+
 	ldx #$08
-*
+!:
 	rts
@@ -1,18 +1,18 @@
-	;; Tokenise a line of BASIC
+// Tokenise a line of BASIC
-	;; Stored at $0200
+// Stored at $0200
-	;; Length in tokenise_work1
+// Length in tokenise_work1
 tokenise_line:
-	;; We need to consider each offset in the string to see if it matches
+	// We need to consider each offset in the string to see if it matches
-	;; a token.  No BASIC keyword is > 7 bytes, so we need to start with that
+	// a token.  No BASIC keyword is > 7 bytes, so we need to start with that
-	;; length (or remaining length of string) and count our way back down.
+	// length (or remaining length of string) and count our way back down.
-	;; This means we need separate start and end points to keep track of.
+	// This means we need separate start and end points to keep track of.
-	;; $0110 = offset into string
+	// $0110 = offset into string
-	;; $0111 = number of bytes to pack
+	// $0111 = number of bytes to pack
-	;; $0112 = offset into tokenised output
+	// $0112 = offset into tokenised output
-	;; $0113 = length of raw string
+	// $0113 = length of raw string
 	lda #$00
 	sta $0110
@@ -24,56 +24,56 @@ tokenise_line:
 tokenise_char:
-	;; Check if we have reached end of the line?
+	// Check if we have reached end of the line?
 	lda $0110
 	cmp $0113
-	bne +
+	bne !+
-	;; End of line reached
+	// End of line reached
-	;; Finished tokenising line
+	// Finished tokenising line
-	;; Update tokenise_work1 and terminate with null
+	// Update tokenise_work1 and terminate with null
 	ldx $0112
 	lda #$00
 	sta $0200,x
 	stx tokenise_work1
-	;; Clear quote mode flag that is also used by KERNAL for screen display
+	// Clear quote mode flag that is also used by KERNAL for screen display
 	lda #$00
 	sta quote_mode_flag
 	rts
-*
+!:
-	;; More to do
+	// More to do
-	;; Maximum keyword length
+	// Maximum keyword length
 	lda #7
 	sta $0111
 tokenise_char_loop:	
-	;; Pack the word from the start (start = X, raw len = tokenise_work1)
+	// Pack the word from the start (start = X, raw len = tokenise_work1)
-	;; Returns packed length in tokenise_work2 and writes the packed
+	// Returns packed length in tokenise_work2 and writes the packed
-	;; word at $0100+
+	// word at $0100+
 	ldx $0110
 	lda $0200,x
 	cmp #$22
 	bne tk_not_quote
-	;; Quote
+	// Quote
 	lda quote_mode_flag
 	eor #$ff
 	sta quote_mode_flag
 	jmp tk_literal_char
 tk_not_quote:
-	;; Check for literal characters in various ranges
+	// Check for literal characters in various ranges
-	;; (This just speeds the tokeniser up, by avoiding the packed token search
+	// (This just speeds the tokeniser up, by avoiding the packed token search
-	;;  for such characters).
+	//  for such characters).
-	;; SPACE and punctuation before +,- and *
+	// SPACE and punctuation before +,- and *
 	cmp #$2a
 	bcc tk_literal_char
-	;; Don't try to tokenise digits
+	// Don't try to tokenise digits
 	cmp #$30
 	bcc tk_might_be_keyword
 	cmp #$3a
@@ -81,41 +81,41 @@ tk_not_quote:
 	jmp tk_literal_char
 tk_might_be_keyword:	
-	;; Don't tokenise in quote mode
+	// Don't tokenise in quote mode
 	lda quote_mode_flag
 	bne tk_literal_char
-	;; Pack string
+	// Pack string
 	ldx $0110
 	lda $0111
 	sta tokenise_work1
-	;; XXX - We should implement an optimisation where we
+	// XXX - We should implement an optimisation where we
-	;; trim the last symbol of successively, instead of re-packing the word
+	// trim the last symbol of successively, instead of re-packing the word
-	;; again with one less char each time.
+	// again with one less char each time.
-	;; XXX - We should limit the word length to the length of interesting chars
+	// XXX - We should limit the word length to the length of interesting chars
-	;; that are available.
+	// that are available.
 	jsr pack_word
 	lda tokenise_work2
 	cmp #$10
-	bcc +
+	bcc !+
-	;; Packed string too long
+	// Packed string too long
 	jmp do_STRING_TOO_LONG_error
-	*
+!:
-	;; Search for it in keywords
+	// Search for it in keywords
 	jsr keyword_search
-	;; Did we find a keyword?
+	// Did we find a keyword?
 	bcc found_token_in_line
-	;; Nope, so try shorter
+	// Nope, so try shorter
 	dec $0111
 	bne tokenise_char_loop
 tk_literal_char:
-	;; Is not a token, so copy to output verbatim
+	// Is not a token, so copy to output verbatim
 	ldx $0110
 	ldy $0112
 	lda $0200,x
@@ -123,68 +123,68 @@ tk_literal_char:
 	inc $0112
 	inc $0110
-	;; Tokenise next char
+	// Tokenise next char
 	jmp tokenise_char
 found_token_in_line:
-	;; Got a token, so write it out
+	// Got a token, so write it out
 	ldx $0112
 	sta $0200,x
 	inx
 	stx $0112
-	;; If it is REM, then lock us in quote mode to the end of the line
+	// If it is REM, then lock us in quote mode to the end of the line
 	cmp #$8f
 	bne not_rem
 	sta quote_mode_flag
 not_rem:	
-	;; Now skip over the length of the token
+	// Now skip over the length of the token
 	lda $0110
 	clc
 	adc $0111
 	sta $0110
-	;; See if there is more of the line left to process
+	// See if there is more of the line left to process
 	jmp tokenise_char
-	;; Search for word in keyword list
+	// Search for word in keyword list
-	;; The packed form is canonical, so we can search for the keyword while
+	// The packed form is canonical, so we can search for the keyword while
-	;; it remains compressed. This also saves a little time.
+	// it remains compressed. This also saves a little time.
-	;; Algorithm is simply to find matching first bytes, and then look for
+	// Algorithm is simply to find matching first bytes, and then look for
-	;; the rest being a match.
+	// the rest being a match.
 keyword_search:
-	;; Search for the compressed keyword stored at $0100 in the list
+	// Search for the compressed keyword stored at $0100 in the list
-	;; of compressed keywords
+	// of compressed keywords
-	;; tokenise_work1 = offset in line of input
+	// tokenise_work1 = offset in line of input
-	;; tokenise_work2 = length of token we are matching
+	// tokenise_work2 = length of token we are matching
-	;; tokenise_work3 = offset in token list
+	// tokenise_work3 = offset in token list
-	;; load_or_verify_or_tokenise_work5 = temporary work space
+	// load_or_verify_or_tokenise_work5 = temporary work space
-	;; X and Y registers used as temporary space.
+	// X and Y registers used as temporary space.
-	;; returns C=1 if no matching token, else C=0 and A=token
+	// returns C=1 if no matching token, else C=0 and A=token
 	lda #$00
 	sta tokenise_work1
 	sta tokenise_work3
 next_kw_offset:	
-	;; Advance offset in compressed keyword list, to see if a match
+	// Advance offset in compressed keyword list, to see if a match
-	;; BEGINS here
+	// BEGINS here
-	;;  Get count of bytes to compare
+	//  Get count of bytes to compare
 	lda tokenise_work2
 	sta load_or_verify_or_tokenise_work5
-	;; Load current position
+	// Load current position
 	ldy tokenise_work3
 	ldx tokenise_work1
-	;; Advance offset in compressed token list, and stop at the end
+	// Advance offset in compressed token list, and stop at the end
 	inc tokenise_work3
 	lda tokenise_work3
 	cmp #packed_keyword_table_len
@@ -194,75 +194,75 @@ next_in_match:
 	lda $0100,x
 	cmp packed_keywords,y
 	bne next_kw_offset
-	;; Advance to next chars in source and target
+	// Advance to next chars in source and target
 	inx
 	iny
-	dec load_or_verify_or_tokenise_work5 	; Have we compared all bytes yet?
+	dec load_or_verify_or_tokenise_work5 	// Have we compared all bytes yet?
 	bne next_in_match
-	;; Keyword matches!
+	// Keyword matches!
-	;; Now make sure we started on a keyword boundary
+	// Now make sure we started on a keyword boundary
-	;; (we know we finished on one, because of the structure of the compressed
+	// (we know we finished on one, because of the structure of the compressed
-	;; keyword data).
+	// keyword data).
-	;; Offset 0
+	// Offset 0
-	;; previous byte is $x0
+	// previous byte is $x0
-	;; two byte prior is $FE
+	// two byte prior is $FE
-	;; Get offset of first byte of this token
+	// Get offset of first byte of this token
 	ldx tokenise_work3
-	dex 			; pointer points one late, so rewind it
+	dex 			// pointer points one late, so rewind it
-	;; At start of list?
+	// At start of list?
 	cpx #$00
 	beq word_boundary
 	dex
-	;; Previous byte is $x0 end token?
+	// Previous byte is $x0 end token?
 	lda packed_keywords,x
 	and #$0f
 	beq word_boundary
 	dex
-	;; Uber-previouss byte is $FE final literal token?
+	// Uber-previouss byte is $FE final literal token?
 	lda packed_keywords,x
 	cmp #$fe
 	beq word_boundary
-	;; Not a word boundary, so ignore
+	// Not a word boundary, so ignore
 	jmp next_kw_offset
 word_boundary:	
-	;; Found a token whose offset is in tokenise_work3
+	// Found a token whose offset is in tokenise_work3
-	;; Now trace back to the start of the compressed keyword list
+	// Now trace back to the start of the compressed keyword list
-	;; to work out what keyword number we are, so that we can return
+	// to work out what keyword number we are, so that we can return
-	;; the token number.
+	// the token number.
 	ldy #$80
 token_count_loop:
 	lda packed_keywords,x
 	cmp #$fe
-	bne +
+	bne !+
 	iny
-*
+!:
 	and #$0f
 	cmp #$00
-	bne +
+	bne !+
 	iny
-*
+!:
 	cpx #$00
-	beq +
+	beq !+
 	dex
 	jmp token_count_loop
-*
+!:
 	tya
 	clc
 	rts
 done_searching_for_token:	
-	;;  No token found
+	//  No token found
 	sec
 	lda #$00
 	rts
@@ -1,19 +1,19 @@
-	;; IMPORTANT:
+// IMPORTANT:
-	;; These routines lengths cannot be changed without changing
+// These routines lengths cannot be changed without changing
-	;; the aliases for peek_under_roms, poke_under_roms etc
+// the aliases for peek_under_roms, poke_under_roms etc
-	;; in ,aliases.s.
+// in ,aliases.s.
-	;; Thus those addresses are expressed using formulae.
+// Thus those addresses are expressed using formulae.
 install_ram_routines:
-	;; Copy routines into place
+	// Copy routines into place
-	ldx #ram_routines_len-1
+	ldx #ram_routines_end-ram_routines_start-1
-*
+!:
 	lda ram_routines_start,x
 	sta tiny_nmi_handler,x
 	dex
-	bpl -
+	bpl !-
-	;; Point NMI handler to tiny_nmi_handler
+	// Point NMI handler to tiny_nmi_handler
 	lda #<tiny_nmi_handler
 	sta $FFFE
 	lda #>tiny_nmi_handler
@@ -23,14 +23,14 @@ install_ram_routines:
 ram_routines_start:	
-	;; XXX - Routine order must match that of the KERNAL version of the file.
+	// XXX - Routine order must match that of the KERNAL version of the file.
-	;; (since it has fewer routines)
+	// (since it has fewer routines)
 tiny_nmi_handler_routine:
 	inc missed_nmi_flag
 	rti
 peek_under_roms_routine:
 	php
-	; Offset of arg of lda ($00),y	
+	// Offset of arg of lda ($00),y	
 	stx peek_under_roms+pa-peek_under_roms_routine+1
 	jsr memmap_allram
 pa:	lda ($00),y
@@ -40,7 +40,7 @@ pa:	lda ($00),y
 poke_under_roms_routine:
 	php
-	; Offset of arg of lda ($00),y	
+	// Offset of arg of lda ($00),y	
 	stx poke_under_roms+pb-poke_under_roms_routine+1
 	jsr memmap_allram
 pb:	sta ($00),y
@@ -64,12 +64,12 @@ memmap_allram_routine:
 	rts
 shift_mem_up_routine:
-	;; Move memmove_size bytes from memmove_src to memmove_dst,
+	// Move memmove_size bytes from memmove_src to memmove_dst,
-	;; where memmove_dst > memmove_src
+	// where memmove_dst > memmove_src
-	;; This means we have to copy from the back end down.
+	// This means we have to copy from the back end down.
-	;; This routine assumes the pointers are already pointed
+	// This routine assumes the pointers are already pointed
-	;; to the end of the areas, and that Y is correctly initialised
+	// to the end of the areas, and that Y is correctly initialised
-	;; to allow the copy to begin.
+	// to allow the copy to begin.
 	php
 	jsr memmap_allram
 smu1:	
@@ -85,12 +85,12 @@ smu1:
 	jmp memmap_normal
 shift_mem_down_routine:
-	;; Move memmove_size bytes from memmove_src to memmove_dst,
+	// Move memmove_size bytes from memmove_src to memmove_dst,
-	;; where memmove_dst > memmove_src
+	// where memmove_dst > memmove_src
-	;; This means we have to copy from the back end down.
+	// This means we have to copy from the back end down.
-	;; This routine assumes the pointers are already pointed
+	// This routine assumes the pointers are already pointed
-	;; to the end of the areas, and that Y is correctly initialised
+	// to the end of the areas, and that Y is correctly initialised
-	;; to allow the copy to begin.
+	// to allow the copy to begin.
 	php
 	jsr memmap_allram
 smd1:
@@ -105,7 +105,4 @@ smd1:
 	plp
 	jmp memmap_normal
 ram_routines_end:
 	.alias ram_routines_len ram_routines_end-ram_routines_start
@@ -1,161 +1,161 @@
-;; START wedge support
+// START wedge support
 wedge_dos:
-	;; Close all the channels, so that wedge has full control
+	// Close all the channels, so that wedge has full control
 	jsr JCLALL
-	;; Set file parameters,  channel 15 is a typical one for commands
+	// Set file parameters,  channel 15 is a typical one for commands
-	jsr select_device ; sets X register
+	jsr select_device // sets .X register
 	lda #$0F
 	ldy #$0F
 	jsr JSETFLS
-	;; Now we have to check what the user wants us to do
+	// Now we have to check what the user wants us to do
-	;; Check if user asked for a status
+	// Check if user asked for a status
 	ldy #$00
 	lda (basic_current_statement_ptr), y
-	bne +
+	bne !+
-	jmp wedge_dos_status ; XXX try to optimize this, perhaps move 'wedge_dos_status' above?
+	jmp wedge_dos_status // XXX try to optimize this, perhaps move 'wedge_dos_status' above?
-*
+!:
-	;; Check if asked for a directory
+	// Check if asked for a directory
 	cmp #$24
-	bne +
+	bne !+
 	jmp wedge_dos_directory
-*
+!:
-	;; Check if asked to change drive number, or if it is a regular command
+	// Check if asked to change drive number, or if it is a regular command
 	cmp #$30
-	bcc wedge_dos_command ; char code before 0
+	bcc wedge_dos_command // char code before 0
 	cmp #$3A
-	bcs wedge_dos_command ; char code after 9
+	bcs wedge_dos_command // char code after 9
 	iny
 	lda (basic_current_statement_ptr), y
-	beq wedge_dos_change_drive ; end of buffer
+	beq wedge_dos_change_drive // end of buffer
 	cmp #$20
 	beq wedge_dos_change_drive
-	jmp -
+	jmp !-
 wedge_dos_command:
-	;; Provide command name
+	// Provide command name
 	jsr wedge_dos_setnam
 	jsr JSETNAM
 	jsr JOPEN
-	bcc +
+	bcc !+
-	jmp wedge_dos_basic_error ; XXX combine with other such jumps
+	jmp wedge_dos_basic_error // XXX combine with other such jumps
-*
+!:
-	;; Retrieve status, print it if not OK
+	// Retrieve status, print it if not OK
 	jsr JCLALL
 	jsr wedge_dos_status_get
 	lda BUF+0
-	cmp #$30 ; '0'
+	cmp #$30 // '0'
 	bne wedge_dos_status_print
 	lda BUF+1
-	cmp #$30 ; '0'
+	cmp #$30 // '0'
 	bne wedge_dos_status_print
-	;; Clean-up and exit
+	// Clean-up and exit
 	jmp wedge_dos_clean_exit
 wedge_dos_change_drive:
-	;; Reuse the line number parser for device number retrieval
+	// Reuse the line number parser for device number retrieval
 	jsr basic_parse_line_number
 	lda basic_line_number+1
-	beq +
+	beq !+
 	jmp do_ILLEGAL_QUANTITY_error
-*
+!:
 	lda basic_line_number+0
 	cmp #$08
-	bpl +
+	bpl !+
-	bcs +
+	bcs !+
 	jmp do_ILLEGAL_DEVICE_NUMBER_error
-*
+!:
 	sta current_device_number
 	jmp basic_end_of_line
 wedge_dos_status_get:
-	;; Here the flow is mostly the same as in the example from
+	// Here the flow is mostly the same as in the example from
-	;; https://codebase64.org/doku.php?id=base:reading_the_error_channel_of_a_disk_drive
+	// https://codebase64.org/doku.php?id=base:reading_the_error_channel_of_a_disk_drive
-	;; Set remaining file parameters, open the channel
+	// Set remaining file parameters, open the channel
-	lda #$00  ; empty file name
+	lda #$00  // empty file name
 	jsr JSETNAM
 	jsr JOPEN
-	bcc +
+	bcc !+
-	jmp wedge_dos_basic_error ; XXX combine with other such jumps
+	jmp wedge_dos_basic_error // XXX combine with other such jumps
-*
+!:
-	;; Set channel for input
+	// Set channel for input
 	ldx #$0F
 	jsr JCHKIN
-	bcc +
+	bcc !+
-	jmp wedge_dos_basic_error ; XXX combine with other such jumps
+	jmp wedge_dos_basic_error // XXX combine with other such jumps
-*
+!:
 	ldy #$00
-*
+!:
-	cpy #$50 ; buffer overflow protection
+	cpy #$50 // buffer overflow protection
-	beq +
+	beq !+
-	jsr JREADST ; retrieve errors
+	jsr JREADST // retrieve errors
-	;; XXX error in case of status != EOF
+	// XXX error in case of status != EOF
-	;; Print out everything retrieved from the drive
+	// Print out everything retrieved from the drive
-	bne +
+	bne !+
 	jsr JCHRIN
 	bcc wedge_dos_x1
-	jmp wedge_dos_basic_error ; XXX try to optimize this
+	jmp wedge_dos_basic_error // XXX try to optimize this
 wedge_dos_x1:
 	sta BUF, y
 	iny
-	jmp -
+	jmp !-
-*
+!:
 	rts
 wedge_dos_status:
 	jsr wedge_dos_status_get
-	;; FALLTROUGH
+	// FALLTROUGH
 wedge_dos_status_print:
-	;; Print buffered status
+	// Print buffered status
 	ldx #$00
-*
+!:
 	dey
-	bmi +
+	bmi !+
 	lda BUF, x
 	jsr JCHROUT
 	inx
-	bne -
+	bne !-
-*
+!:
-	;; Clean-up and exit
+	// Clean-up and exit
 	jmp wedge_dos_clean_exit
 wedge_dos_directory:
-	;; First change the secondary address to the one suitable for
+	// First change the secondary address to the one suitable for
-	;; directory loading
+	// directory loading
-	lda #$00 ; logical device number
+	lda #$00 // logical device number
 	ldx current_device_number
 	ldy #$60
 	jsr JSETFLS
-	;; Provide file name
+	// Provide file name
 	jsr wedge_dos_setnam
-	;; Open the file
+	// Open the file
 	jsr JOPEN
 	bcs wedge_dos_basic_error
-	;; Set channel for file reading
+	// Set channel for file reading
 	ldx #$00
 	jsr JCHKIN
 	bcs wedge_dos_basic_error
-	;; Ignore start address (2 first bytes) - XXX check for errors
+	// Ignore start address (2 first bytes) - XXX check for errors
 	jsr JCHRIN
 	bcs wedge_dos_basic_error
 	jsr JCHRIN
@@ -163,37 +163,37 @@ wedge_dos_directory:
 wedge_dos_directory_line:
-	;; Load a single line, reuse BASIC input buffer
+	// Load a single line, reuse BASIC input buffer
 	ldy #$FF
-*
+!:
 	iny
 	jsr JCHRIN
 	bcs wedge_dos_basic_error
 	sta BUF, y
 	cpy #$50
-	beq + ; line too long, terminate loading file
+	beq !+ // line too long, terminate loading file
 	jsr JREADST
-	bne + ; end of file
+	bne !+ // end of file
-	cpy #$04 ; 2 bytes (pointer to next line) + 2 bytes (line number) 
+	cpy #$04 // 2 bytes (pointer to next line) + 2 bytes (line number) 
-	bcc -
+	bcc !-
 	lda BUF, y
-	bne -
+	bne !-
-	;; End of line, but not end of file
+	// End of line, but not end of file
 	beq wedge_dos_directory_display
-*
+!:
 	lda #K_STS_END_OF_FILE
-	sta IOSTATUS ; make sure end of file is marked
+	sta IOSTATUS // make sure end of file is marked
-	;; FALLTROUGH
+	// FALLTROUGH
 wedge_dos_directory_display:
-	cpy #$05 ; protection against malformed directory
+	cpy #$05 // protection against malformed directory
 	bcc wedge_dos_clean_exit
-	lda #$00 ; extra protection agains buffer overflow
+	lda #$00 // extra protection agains buffer overflow
 	sta BUF, y
-	;; Display line
+	// Display line
 	ldx #<BUF
 	stx basic_current_line_ptr+0
 	ldx #>BUF
@@ -201,14 +201,14 @@ wedge_dos_directory_display:
 	ldx #basic_current_line_ptr
 	jsr list_single_line
-	;; Read & display next line or quit
+	// Read & display next line or quit
 	lda IOSTATUS
 	beq wedge_dos_directory_line
-	;; FALLTROUGH
+	// FALLTROUGH
 wedge_dos_clean_exit:
 	jsr JCLALL
-	;; Print new line
+	// Print new line
 	lda #$0D
 	jsr JCHROUT
 	jmp basic_end_of_line
@@ -222,17 +222,17 @@ wedge_dos_basic_error:
 	jmp do_basic_error
 wedge_dos_setnam:
-	;; Now determine the length of the 'file' name
+	// Now determine the length of the 'file' name
 	ldy #$FF
-*
+!:
 	iny
 	lda (basic_current_statement_ptr), y
-	bne -
+	bne !-
-	;; Set the name to open
+	// Set the name to open
 	tya
 	ldx basic_current_statement_ptr+0
 	ldy basic_current_statement_ptr+1
 	jmp JSETNAM
-;; END wedge support
+// END wedge support
@@ -1,73 +1,75 @@
-;	Names of ZP and low memory locations
+// Names of ZP and low memory locations
-;	(Only those of relevance for the KERNAL)
+// (Only those of relevance for the KERNAL)
-;	(And only those for now that we feel the need to implement initially)
+// (And only those for now that we feel the need to implement initially)
-;	(https://www.c64-wiki.com/wiki/Zeropage)
+// (https://www.c64-wiki.com/wiki/Zeropage)
-	.alias kernal_load_or_verify_flag $93
+// XXX get rid of this file, use ,aliases_ram_lowmem.s instead
 	.alias current_file_num $98
 	.alias input_device_number DFLTN
 	.alias cassette_buffer_bytes_used $A6
 	.alias load_or_scroll_temp_pointer $AC
 	;; We also use the following for temp colour pointer when scrolling
 	.alias load_save_verify_end_address $AE
 	.alias cassette_buffer_ptr $B2
 	.alias current_logical_filenum $B8
 	.alias current_secondary_address $B9
 	.alias current_device_number $BA
 	.alias current_filename_ptr $BB
 	.alias load_save_end_ptr $C3
 	.alias last_key_matrix_position $C5
 	.alias keys_in_key_buffer $C6
 	.alias reverse_video_flag $C7
 	.alias end_of_input_line $C8
 	.alias start_of_keyboard_input $C9
 	.alias current_key_index_entry $CB
 	.alias cursor_blink_disable $CC
 	.alias cursor_blink_countdown $CD
 	.alias cursor_saved_character $CE
 	.alias cursor_is_visible $CF
 	.alias keyboard_input_ready $D0
 	.alias current_screen_line_ptr $D1
 	.alias current_screen_x $D3
 	.alias quote_mode_flag $D4
 	.alias logical_line_length $D5
 	.alias current_screen_y $D6
 	.alias last_printed_character_ascii $D7
 	.alias insert_mode $D8
 	; Bits 0 -3 = bits 8-11 of screen line address
 	; Bit 7 = line spans multiple physical lines
 	.alias screen_line_link_table $D9
 	.alias current_screen_line_colour_ptr $F3
 	.alias keyboard_decoding_table_ptr $F5
 	.alias rs232_rx_buffer_ptr $F7
 	.alias rs232_tx_buffer_ptr $F9
-	; "Compute's Mapping the 64" book
+	.label kernal_load_or_verify_flag = $93
-	.alias keyboard_buffer $0277
+	.label current_file_num = $98
-	.alias text_colour $0286 ; p55
+	.label input_device_number = DFLTN
-	.alias colour_under_cursor $0287 ; p56
+	.label cassette_buffer_bytes_used = $A6
-	.alias key_buffer_size $0289 ; p57
+	.label load_or_scroll_temp_pointer = $AC
 	// We also use the following for temp colour pointer when scrolling
 	.label load_save_verify_end_address = $AE
 	.label cassette_buffer_ptr = $B2
 	.label current_logical_filenum = $B8
 	.label current_secondary_address = $B9
 	.label current_device_number = $BA
 	.label current_filename_ptr = $BB
 	.label load_save_end_ptr = $C3
 	.label last_key_matrix_position = $C5
 	.label keys_in_key_buffer = $C6
 	.label reverse_video_flag = $C7
 	.label end_of_input_line = $C8
 	.label start_of_keyboard_input = $C9
 	.label current_key_index_entry = $CB
 	.label cursor_blink_disable = $CC
 	.label cursor_blink_countdown = $CD
 	.label cursor_saved_character = $CE
 	.label cursor_is_visible = $CF
 	.label keyboard_input_ready = $D0
 	.label current_screen_line_ptr = $D1
 	.label current_screen_x = $D3
 	.label quote_mode_flag = $D4
 	.label logical_line_length = $D5
 	.label current_screen_y = $D6
 	.label last_printed_character_ascii = $D7
 	.label insert_mode = $D8
 	// Bits 0 -3 = bits 8-11 of screen line address
 	// Bit 7 = line spans multiple physical lines
 	.label screen_line_link_table = $D9
 	.label current_screen_line_colour_ptr = $F3
 	.label keyboard_decoding_table_ptr = $F5
 	.label rs232_rx_buffer_ptr = $F7
 	.label rs232_tx_buffer_ptr = $F9
-	;; 0 = cursor keys, insert, delete and space repeat, but nothing else
+	// "Compute's Mapping the 64" book
-	;; 128 = all keys repeat
+	.label keyboard_buffer = $0277
-	;; 64 = no keys repeat
+	.label text_colour = $0286 // p55
-	.alias key_repeat_flags $028A ; p58
+	.label colour_under_cursor = $0287 // p56
-	;; https://www.c64-wiki.com/wiki/Page_2
+	.label key_buffer_size = $0289 // p57
 	.alias key_repeat_counter $028B
 	.alias key_first_repeat_delay $028C
 	;; bit 0 = shift, 1 = Vendor Key, 2 = Control
 	.alias key_bucky_state $028D
 	.alias key_last_bucky_state $028E
 	.alias keyboard_decoding_ptr $028F
 	.alias enable_case_switch $0291
 	.alias screen_scroll_disable $0292
-	;; Under-ROM routines
+	// 0 = cursor keys, insert, delete and space repeat, but nothing else
-	;; (BASIC also includes them. XXX - We should de-duplicate them in a safe manner)
+	// 128 = all keys repeat
-	.alias missed_nmi_flag         $2A7
+	// 64 = no keys repeat
-	.alias tiny_nmi_handler		$2A8	
+	.label key_repeat_flags = $028A // p58
-	.alias peek_under_roms tiny_nmi_handler+peek_under_roms_routine-tiny_nmi_handler_routine
+	// https://www.c64-wiki.com/wiki/Page_2
-	.alias poke_under_roms tiny_nmi_handler+poke_under_roms_routine-tiny_nmi_handler_routine
+	.label key_repeat_counter = $028B
-	.alias memmap_allram tiny_nmi_handler+memmap_allram_routine-tiny_nmi_handler_routine
+	.label key_first_repeat_delay = $028C
-	.alias memmap_normal tiny_nmi_handler+memmap_normal_routine-tiny_nmi_handler_routine
+	// bit 0 = shift, 1 = Vendor Key, 2 = Control
 	.label key_bucky_state = $028D
 	.label key_last_bucky_state = $028E
 	.label keyboard_decoding_ptr = $028F
 	.label enable_case_switch = $0291
 	.label screen_scroll_disable = $0292
 	// Under-ROM routines
 	// (BASIC also includes them. XXX - We should de-duplicate them in a safe manner)
 	.label missed_nmi_flag = $2A7
 	.label tiny_nmi_handler = $2A8	
 	.label peek_under_roms = tiny_nmi_handler+peek_under_roms_routine-tiny_nmi_handler_routine
 	.label poke_under_roms = tiny_nmi_handler+poke_under_roms_routine-tiny_nmi_handler_routine
 	.label memmap_allram = tiny_nmi_handler+memmap_allram_routine-tiny_nmi_handler_routine
 	.label memmap_normal = tiny_nmi_handler+memmap_normal_routine-tiny_nmi_handler_routine
@@ -1,6 +1,6 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_LOAD
+.macro TARGET_HOOK_LOAD() {
-.macend
+}
@@ -1,6 +1,6 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_LOAD
+.macro TARGET_HOOK_LOAD() {
-.macend
+}
@@ -1,57 +1,57 @@
-;; Registers according to Ultimate 64 Command Interface description,
+// Registers according to Ultimate 64 Command Interface description,
-;; https://1541u-documentation.readthedocs.io/en/latest/command%20interface.html
+// https://1541u-documentation.readthedocs.io/en/latest/command%20interface.html
-;; and ultimate_dos_v1.0.pdf and command_interface_v1.0.pdf by Gideon Zweijtzer
+// and ultimate_dos_v1.0.pdf and command_interface_v1.0.pdf by Gideon Zweijtzer
-	;; Command interface registers
+	// Command interface registers
-	.alias U64_CONTROL                 $DF1C ; write
+	.label U64_CONTROL                 = $DF1C // write
-	.alias U64_STATUS                  $DF1C ; read
+	.label U64_STATUS                  = $DF1C // read
-	.alias U64_COMMAND_DATA            $DF1D ; write
+	.label U64_COMMAND_DATA            = $DF1D // write
-	.alias U64_IDENTIFICATION          $DF1D ; read
+	.label U64_IDENTIFICATION          = $DF1D // read
-	.alias U64_RESPONSE_DATA           $DF1E ; read only
+	.label U64_RESPONSE_DATA           = $DF1E // read only
-	.alias U64_STATUS_DATA             $DF1F ; read only
+	.label U64_STATUS_DATA             = $DF1F // read only
-	;; Constant for U64_IDENTIFICATION register
+	// Constant for U64_IDENTIFICATION register
-	.alias U64_MAGIC_ID                $C9
+	.const U64_MAGIC_ID                = $C9
-	;; Constants for U64_CONTROL register
+	// Constants for U64_CONTROL register
-	.alias U64_CTRL_BIT_PUSH_CMD       $01
+	.const U64_CTRL_BIT_PUSH_CMD       = $01
-	.alias U64_CTRL_BIT_DATA_ACC       $02
+	.const U64_CTRL_BIT_DATA_ACC       = $02
-	.alias U64_CTRL_BIT_ABORT          $04
+	.const U64_CTRL_BIT_ABORT          = $04
-	.alias U64_CTRL_BIT_CLR_ERR        $08
+	.const U64_CTRL_BIT_CLR_ERR        = $08
-	;; Constants for U64_STATUS register
+	// Constants for U64_STATUS register
-	.alias U64_STAT_BIT_CMD_BUSY       $01
+	.const U64_STAT_BIT_CMD_BUSY       = $01
-	.alias U64_STAT_BIT_DATA_ACC       $02
+	.const U64_STAT_BIT_DATA_ACC       = $02
-	.alias U64_STAT_BIT_ABORT_P        $04
+	.const U64_STAT_BIT_ABORT_P        = $04
-	.alias U64_STAT_BIT_ERROR          $08
+	.const U64_STAT_BIT_ERROR          = $08
-	.alias U64_STAT_MASK_STATE         $30 ; two bits!
+	.const U64_STAT_MASK_STATE         = $30 // two bits!
-	.alias U64_STAT_BIT_STAT_AV        $40
+	.const U64_STAT_BIT_STAT_AV        = $40
-	.alias U64_STAT_BIT_DATA_AV        $80
+	.const U64_STAT_BIT_DATA_AV        = $80
-	;; Interface targets
+	// Interface targets
-	.alias U64_TARGET_DOS1             $01
+	.const U64_TARGET_DOS1             = $01
-	.alias U64_TARGET_DOS2             $02
+	.const U64_TARGET_DOS2             = $02
-	;; DOS command codes
+	// DOS command codes
-	.alias U64_DOS_CMD_IDENTIFY        $01
+	.const U64_DOS_CMD_IDENTIFY        = $01
-	.alias U64_DOS_CMD_OPEN_FILE       $02
+	.const U64_DOS_CMD_OPEN_FILE       = $02
-	.alias U64_DOS_CMD_CLOSE_FILE      $03
+	.const U64_DOS_CMD_CLOSE_FILE      = $03
-	.alias U64_DOS_CMD_READ_DATA       $04
+	.const U64_DOS_CMD_READ_DATA       = $04
-	.alias U64_DOS_CMD_WRITE_DATA      $05
+	.const U64_DOS_CMD_WRITE_DATA      = $05
-	.alias U64_DOS_CMD_FILE_SEEK       $06
+	.const U64_DOS_CMD_FILE_SEEK       = $06
-	.alias U64_DOS_CMD_FILE_INFO       $07
+	.const U64_DOS_CMD_FILE_INFO       = $07
-	.alias U64_DOS_CMD_CHANGE_DIR      $11
+	.const U64_DOS_CMD_CHANGE_DIR      = $11
-	.alias U64_DOS_CMD_GET_PATH        $12
+	.const U64_DOS_CMD_GET_PATH        = $12
-	.alias U64_DOS_CMD_OPEN_DIR        $13
+	.const U64_DOS_CMD_OPEN_DIR        = $13
-	.alias U64_DOS_CMD_READ_DIR        $14
+	.const U64_DOS_CMD_READ_DIR        = $14
-	.alias U64_DOS_CMD_COPY_UI_PATH    $15
+	.const U64_DOS_CMD_COPY_UI_PATH    = $15
-	.alias U64_DOS_CMD_LOAD_REU        $21
+	.const U64_DOS_CMD_LOAD_REU        = $21
-	.alias U64_DOS_CMD_SAVE_REU        $22
+	.const U64_DOS_CMD_SAVE_REU        = $22
-	.alias U64_DOS_CMD_ECHO            $F0
+	.const U64_DOS_CMD_ECHO            = $F0
-	;; DOS file opening constants 
+	// DOS file opening constants 
-	.alias U64_FA_READ                 $01
+	.const U64_FA_READ                 = $01
-	.alias U64_FA_WRITE                $02
+	.const U64_FA_WRITE                = $02
-	.alias U64_FA_CREATE_NEW           $03
+	.const U64_FA_CREATE_NEW           = $03
-	.alias U64_FA_CREATE_ALWAYS        $04
+	.const U64_FA_CREATE_ALWAYS        = $04
@@ -1,9 +1,9 @@
-;; Target-specific hooks
+// Target-specific hooks
-.macro TARGET_HOOK_LOAD
+.macro TARGET_HOOK_LOAD() {
-	;; XXX disabled for now - the current file opening API is not
+	// XXX disabled for now - the current file opening API is not
-	;;     really suitable for easy usage from Kernal
+	//     really suitable for easy usage from Kernal
-	;; jsr u64_load
+	// jsr u64_load
-.macend
+}
@@ -1,35 +1,35 @@
-;;
+//
-;; LOAD routine hook for fast loading via UltiDOS
+// LOAD routine hook for fast loading via UltiDOS
-;;
+//
 u64_load:
-	;; First check whether the command interface is enabled
+	// First check whether the command interface is enabled
 	lda U64_IDENTIFICATION
 	cmp #U64_MAGIC_ID
-	beq +
+	beq !+
 u64_load_skip:
 	rts
-*
+!:
-	;; XXX find out which device number softIEC is mapped to
+	// XXX find out which device number softIEC is mapped to
 	lda current_device_number
-	cmp #$20 ; for now use device number 32
+	cmp #$20 // for now use device number 32
 	bne u64_load_skip
-	;; Takeover the flow completely
+	// Takeover the flow completely
 	pla
 	pla
-	;; Display SEARCHING FOR + filename
+	// Display SEARCHING FOR + filename
 	jsr lvs_display_searching_for
-	;; Whatever the interface was doing - ask to abort it
+	// Whatever the interface was doing - ask to abort it
 	jsr u64_load_abort
-	;; Send a command to open the file
+	// Send a command to open the file
 	lda #U64_DOS_CMD_OPEN_FILE
 	jsr u64_load_send_cmd
 	lda #U64_FA_READ
@@ -37,16 +37,17 @@ u64_load_skip:
 	jsr u64_load_send_filename
 	jsr u64_load_finalize_cmd
-	;; Check status
+	// Check status
 	jsr u64_load_check_status
 	bcs lvs_file_not_found_error
-	;; Load first two bytes to determine start address
+	// Load first two bytes to determine start address
-	;; XXX
+	// XXX
 	jsr printf
-	.byte "DBG: NOT IMPLEMENTED",$0D,0
+	.text "DBG: NOT IMPLEMENTED"
 	.byte $0D,0
 	jmp lvs_wrap_around_error
 	rts
@@ -54,25 +55,25 @@ u64_load_skip:
 u64_load_abort:
 	lda #U64_CTRL_BIT_ABORT
 	sta U64_CONTROL
-*
+!:
 	lda U64_STATUS
-	bne -
+	bne !-
 	rts
 u64_load_send_cmd:
 	ldx #U64_TARGET_DOS2
-	stx U64_COMMAND_DATA ; target
+	stx U64_COMMAND_DATA // target
-	sta U64_COMMAND_DATA ; command code
+	sta U64_COMMAND_DATA // command code
 	rts
 u64_load_send_filename:
 	ldy #0
 u64_load_send_filename_loop:
 	cpy FNLEN
-	bne+
+	bne !+
 	rts
-*
+!:
 	ldx #<current_filename_ptr
 	jsr peek_under_roms
 	iny
@@ -81,50 +82,50 @@ u64_load_send_filename_loop:
 	jmp u64_load_send_filename_loop
 u64_load_finalize_cmd:
-	;; Push the command for execution
+	// Push the command for execution
 	lda #U64_CTRL_BIT_PUSH_CMD
 	sta U64_CONTROL
-	;; Wait till it is complete
+	// Wait till it is complete
-*
+!:
 	lda U64_STATUS
 	and #U64_STAT_BIT_CMD_BUSY
-	bne -
+	bne !-
 	rts
 u64_load_check_status:
-	;; Wait till status is available
+	// Wait till status is available
 	lda U64_STATUS
 	and #U64_STAT_BIT_STAT_AV
 	beq u64_load_check_status
-	;; Status is ready - check the first character
+	// Status is ready - check the first character
 	lda U64_STATUS_DATA
-	jsr JCHROUT ; XXX for test only
+	jsr JCHROUT // XXX for test only
-	cmp #$30 ; '0'
+	cmp #$30 // '0'
 	bne u64_load_check_status_wrong
-	;; Check the second status character
+	// Check the second status character
 	lda U64_STATUS
 	and #U64_STAT_BIT_STAT_AV
 	beq u64_load_check_status_ok
 	lda U64_STATUS_DATA
-	jsr JCHROUT ; XXX for test only
+	jsr JCHROUT // XXX for test only
-	cmp #$30 ; '0'
+	cmp #$30 // '0'
 	beq u64_load_check_status_ok
-	;; FALLTROUGH
+	// FALLTROUGH
 u64_load_check_status_wrong:
 	sec
-	bcs +
+	bcs !+
 u64_load_check_status_ok:
 	clc
-*
+!:
-	;; Now empty the status queue
+	// Now empty the status queue
 	lda U64_STATUS
 	and #U64_STAT_BIT_STAT_AV
-	beq +
+	beq !+
 	lda U64_STATUS_DATA
-	jsr JCHROUT ; XXX for test only
+	jsr JCHROUT // XXX for test only
-	jmp -
+	jmp !-
-*
+!:
 	rts
@@ -1,15 +1,14 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 274
+// - [RG64] C64 Programmer's Reference Guide   - page 274
-;; - [CM64] Compute's Mapping the Commodore 64 - page 224/225
+// - [CM64] Compute's Mapping the Commodore 64 - page 224/225
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
-acptr:
+ACPTR:
 	jsr kernalstatus_reset
 	jmp iec_rx_byte
@@ -1,41 +1,41 @@
-	;; We have the following variables:
+// We have the following variables:
-	;; cursor_blink_disable
+// cursor_blink_disable
-	;; cursor_blink_countdown
+// cursor_blink_countdown
-	;; cursor_saved_character
+// cursor_saved_character
-	;; cursor_is_visible
+// cursor_is_visible
-	;; colour_under_cursor
+// colour_under_cursor
 show_cursor_if_enabled:
 	lda cursor_blink_disable
-	beq +
+	beq !+
 	rts
-*	lda cursor_is_visible
+!:	lda cursor_is_visible
 	beq show_cursor
 	rts
 show_cursor:
-	;; Set cursor as though it had just finished the off phase,
+	// Set cursor as though it had just finished the off phase,
-	;; so that the call to blink_cursor paints it
+	// so that the call to blink_cursor paints it
 	lda #$00
 	sta cursor_blink_countdown
 	sta cursor_is_visible
 	jsr blink_cursor
-	;; Then set the timeout to 1 frame, so that the cursor
+	// Then set the timeout to 1 frame, so that the cursor
-	;; blinks under key repeat conditions, like on the original KERNAL
+	// blinks under key repeat conditions, like on the original KERNAL
 	lda #$01
 	sta cursor_blink_countdown
 	rts
 blink_cursor:
-	;; Is the cursor enabled?
+	// Is the cursor enabled?
 	lda cursor_blink_disable
 	bne no_blink_cursor
-	;; Do we need to redraw things?
+	// Do we need to redraw things?
 	dec cursor_blink_countdown
 	bpl no_blink_cursor
-	;; Check if cursor was visible or not, and toggle
+	// Check if cursor was visible or not, and toggle
 	lda cursor_is_visible
 	bne undraw_cursor
 draw_cursor:
@@ -46,7 +46,7 @@ draw_cursor:
 	sta cursor_saved_character	
 	eor #$80
 	sta (current_screen_line_ptr),y
-	;; Also set cursor colour
+	// Also set cursor colour
 	lda (current_screen_line_colour_ptr),y
 	sta colour_under_cursor
 	lda text_colour
@@ -68,10 +68,10 @@ undraw_cursor:
 	lda #0
 	sta cursor_is_visible
-	;; Fall through
+	// Fall through
 reset_blink_timer:	
-	;; Rest blink counter
+	// Rest blink counter
-	;; (Compute's Mapping the 64, p39-40)
+	// (Compute's Mapping the 64, p39-40)
 	lda #20
 	sta cursor_blink_countdown
 no_blink_cursor:
@@ -80,7 +80,7 @@ no_blink_cursor:
 disable_cursor:
 	lda #$80
 	sta cursor_blink_disable
-	;; FALL THROUGH
+	// FALL THROUGH
 hide_cursor_if_visible:
 	lda cursor_is_visible
 	bne undraw_cursor
@@ -1,4 +1,4 @@
-; c64 prg p263
+// c64 prg p263
 cartridge_check:
 	ldx #$04
@@ -1,64 +1,64 @@
-;;
+//
-;; Official Kernal routines, described in:
+// Official Kernal routines, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 275 (CHKIN) / 276 (CKOUT)
+// - [RG64] C64 Programmer's Reference Guide   - page 275 (CHKIN) / 276 (CKOUT)
-;; - [CM64] Compute's Mapping the Commodore 64 - page 229
+// - [CM64] Compute's Mapping the Commodore 64 - page 229
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
-;; CHKIN implementation
+// CHKIN implementation
 chkin_real:
-	;; Store Y for preservation
+	// Store Y for preservation
 	tya
 	pha
-	;; Reset status
+	// Reset status
 	jsr kernalstatus_reset
-	;; First retrieve the FAT/LAT/SAT table index (and check if file is open)
+	// First retrieve the FAT/LAT/SAT table index (and check if file is open)
 	txa
 	jsr find_fls
 	bcs chkinout_file_not_open
-	;; Now we have table index in Y - first filter out unsuitable devices
+	// Now we have table index in Y - first filter out unsuitable devices
 	lda FAT,Y
 	cmp #$01
-	beq chkinout_device_not_present ; tape not implemented
+	beq chkinout_device_not_present // tape not implemented
 	cmp #$02
-	beq chkinout_device_not_present ; RS-232 not implemented
+	beq chkinout_device_not_present // RS-232 not implemented
-	;; Fail if the file is open for writing (secondary address 1)
+	// Fail if the file is open for writing (secondary address 1)
 	lda LAT, Y
 	cmp #$01
 	beq chkinout_file_not_input
-	;; For IEC devices, send TALK + TKSA first
+	// For IEC devices, send TALK + TKSA first
 	lda FAT,Y
 	jsr iec_check_devnum
 	bcs chkin_set_device
-	jsr talk
+	jsr TALK
-	bcs chkinout_device_not_present ; don't set DFLTN in case of failure
+	bcs chkinout_device_not_present // don't set DFLTN in case of failure
 	lda LAT, Y
-	jsr tksa
+	jsr TKSA
 	bcs chkinout_device_not_present
 chkin_set_device:
 	lda FAT,Y
 	sta DFLTN
-	clc ; for success
+	clc // for success
-	;; FALLTROUGH
+	// FALLTROUGH
-;; Common part for booth CHKIN and CKOUT
+// Common part for booth CHKIN and CKOUT
 chkinout_end:
 	tax
@@ -88,54 +88,54 @@ chkinout_file_not_output:
 	tay
 	jmp kernalerror_FILE_NOT_OUTPUT
-;; CKOUT implementation
+// CKOUT implementation
 ckout_real:
-	;; Store Y for preservation
+	// Store Y for preservation
 	tya
 	pha
-	;; Reset status
+	// Reset status
 	jsr kernalstatus_reset
-	;; First retrieve the FAT/LAT/SAT table index (and check if file is open)
+	// First retrieve the FAT/LAT/SAT table index (and check if file is open)
 	txa
 	jsr find_fls
 	bcs chkinout_file_not_open
-	;; Now we have table index in Y - first filter out unsuitable devices
+	// Now we have table index in Y - first filter out unsuitable devices
 	lda FAT,Y
 	cmp #$01
-	beq chkinout_device_not_present ; tape not implemented
+	beq chkinout_device_not_present // tape not implemented
 	cmp #$02
-	beq chkinout_device_not_present ; RS-232 not implemented
+	beq chkinout_device_not_present // RS-232 not implemented
 	cmp #$00
-	beq chkinout_file_not_output ; cannot output to keyboard - XXX check real ROM behaviour
+	beq chkinout_file_not_output // cannot output to keyboard - XXX check real ROM behaviour
-	;; Fail if the file is open for reading (secondary address 0)
+	// Fail if the file is open for reading (secondary address 0)
 	lda LAT, Y
 	beq chkinout_file_not_output
-	;; For IEC devices, send LISTEN + SECOND first
+	// For IEC devices, send LISTEN + SECOND first
 	lda FAT,Y
 	jsr iec_check_devnum
 	bcs chkout_set_device
-	jsr listen
+	jsr LISTEN
-	bcs chkinout_device_not_present ; don't set DFLTO in case of failure
+	bcs chkinout_device_not_present // don't set DFLTO in case of failure
 	lda LAT, Y
-	jsr second
+	jsr SECOND
 	bcs chkinout_device_not_present
 chkout_set_device:
 	lda FAT,Y
 	sta DFLTO
-	clc ; for success
+	clc // for success
 	jmp chkinout_end
@@ -1,67 +1,67 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 277/278
+// - [RG64] C64 Programmer's Reference Guide   - page 277/278
-;; - [CM64] Compute's Mapping the Commodore 64 - page 228
+// - [CM64] Compute's Mapping the Commodore 64 - page 228
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
-;; XXX keyboard part currently does not preserve register Y, to be fixed!
+// XXX keyboard part currently does not preserve register Y, to be fixed!
-;; Reads a byte of input, unless from keyboard.
+// Reads a byte of input, unless from keyboard.
-;; If from keyboard, then it gets a whole line of input, and returns the first char.
+// If from keyboard, then it gets a whole line of input, and returns the first char.
-;; Repeated calls after that read out the successive bytes of the line of input.
+// Repeated calls after that read out the successive bytes of the line of input.
 chrin_real:
-	;; Determine the device number
+	// Determine the device number
 	lda DFLTN
-	beq chrin_keyboard ; #$00 - keyboard
+	beq chrin_keyboard // #$00 - keyboard
-	;; XXX add screen support
+	// XXX add screen support
 	jsr iec_check_devnum
 	bcc chrin_iec
-	jmp lvs_device_not_found_error ;  not a supported device
+	jmp lvs_device_not_found_error // not a supported device
 chrin_iec:
 	jsr JACPTR
 	bcs chrin_done_fail
-	;; FALLTROUGH
+	// FALLTROUGH
 chrin_done:
-	clc ; indicate success
+	clc // indicate success
 	rts
 chrin_done_fail:
-	sec ; indicate failure
+	sec // indicate failure
 	rts
 chrin_keyboard:
-	;; Save X
+	// Save X
 	txa
 	pha
 chrin_repeat:
-	;; Do we have a line of input we are currently returning?
+	// Do we have a line of input we are currently returning?
-	;; If so, return the next byte, and clear the flag when we reach the end.
+	// If so, return the next byte, and clear the flag when we reach the end.
-	;; Do we have a line of input waiting?
+	// Do we have a line of input waiting?
 	lda keyboard_input_ready
 	beq read_from_keyboard
-	;; Yes, we have input waiting at (start_of_keyboard_input)+keyboard_input_ready
+	// Yes, we have input waiting at (start_of_keyboard_input)+keyboard_input_ready
-	;; When keyboard_input_ready = end_of_input_line, then we return a carriage return
+	// When keyboard_input_ready = end_of_input_line, then we return a carriage return
-	;; and clear the flag
+	// and clear the flag
 	cmp end_of_input_line
 	bne not_end_of_input
-	;; Return carriage return and clear pending input flag
+	// Return carriage return and clear pending input flag
 	lda #$00
 	sta keyboard_input_ready
 	pla
@@ -71,7 +71,7 @@ chrin_repeat:
 	rts
 not_end_of_input:
-	;; Return next byte of waiting input and advance index
+	// Return next byte of waiting input and advance index
 	tay
 	pla
 	tax
@@ -86,7 +86,7 @@ read_from_keyboard:
 	jsr enable_cursor
-	;; Wait for a key
+	// Wait for a key
 	lda keys_in_key_buffer
 	beq chrin_repeat
@@ -100,31 +100,31 @@ read_from_keyboard:
 	jsr hide_cursor_if_visible
-	;; It was enter.
+	// It was enter.
-	;; Note that we have a line of input to return, and return the first byte thereof
+	// Note that we have a line of input to return, and return the first byte thereof
-	;; after computing and storing its length.
+	// after computing and storing its length.
-	;; (Compute's Mapping the 64, p96)
+	// (Compute's Mapping the 64, p96)
-	;; Set pointer to line of input
+	// Set pointer to line of input
 	lda current_screen_line_ptr+0
 	sta start_of_keyboard_input+0
 	lda current_screen_line_ptr+1
 	sta start_of_keyboard_input+1
-	;; Calculate length
+	// Calculate length
 	jsr get_current_line_logical_length
 	tay
 	iny
-*	dey
+!:	dey
 	bmi empty_line
 	lda (current_screen_line_ptr),y
 	cmp #$20
-	beq -
+	beq !-
 	iny
 	sty end_of_input_line
 	lda #$01
 	sta keyboard_input_ready
-	;; Return first char of line
+	// Return first char of line
 	ldy #$00
 	pla
 	tax
@@ -134,9 +134,9 @@ read_from_keyboard:
 	rts
 empty_line:
-	;; For an empty line, just return the carriage return
+	// For an empty line, just return the carriage return
-	;; (and don't forget to actually print the carriage return, so that
+	// (and don't forget to actually print the carriage return, so that
-	;; the cursor advances and screen scrolls as required)
+	// the cursor advances and screen scrolls as required)
 	pla
 	tax
 	clc
@@ -144,28 +144,28 @@ empty_line:
 	rts
 not_enter:
-	;; Print character
+	// Print character
 	lda keyboard_buffer
-	jsr chrout
+	jsr CHROUT
 	jsr pop_keyboard_buffer
-	;; Keep looking for input from keyboard until carriage return
+	// Keep looking for input from keyboard until carriage return
 	jmp chrin_repeat
 pop_keyboard_buffer:
-	;; Pop key out of keyboard buffer
+	// Pop key out of keyboard buffer
-	;; Disable interrupts while reading from keyboard buffer
+	// Disable interrupts while reading from keyboard buffer
-	;; so that no race conditions can occur
+	// so that no race conditions can occur
 	sei
 	ldx #$00
 	ldy #$01
-*	lda keyboard_buffer,y
+!:	lda keyboard_buffer,y
 	sta keyboard_buffer,x
 	inx
 	iny
 	cpy key_buffer_size
-	bne -
+	bne !-
 	dec keys_in_key_buffer
 	cli
@@ -199,12 +199,12 @@ not_shifted:
 	cmp #$80
 	bcs not_vendor
-	;; $60-$7F -> $A0-$BF
+	// $60-$7F -> $A0-$BF
 	clc
 	adc #$40
-	;; FALLTROUGH
+	// FALLTROUGH
 not_vendor:
 	rts
@@ -1,36 +1,36 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 278/279
+// - [RG64] C64 Programmer's Reference Guide   - page 278/279
-;; - [CM64] Compute's Mapping the Commodore 64 - page 228
+// - [CM64] Compute's Mapping the Commodore 64 - page 228
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
 chrout_real:
 	sta last_printed_character_ascii
-	;; Save X and Y values
+	// Save X and Y values
-	;; (Confirmed by writing a test program that X and Y
+	// (Confirmed by writing a test program that X and Y
-	;; don't get modified, in agreement with C64 PRG's
+	// don't get modified, in agreement with C64 PRG's
-	;; description of CHROUT)
+	// description of CHROUT)
 	txa
 	pha
 	tya
 	pha
 	php
-	;; Determine the device number
+	// Determine the device number
 	lda DFLTO
-	cmp #$03 ; screen
+	cmp #$03 // screen
 	beq chrout_screen
 	jsr iec_check_devnum
-	bcs chrout_done_unknown_device ; not a supported device
+	bcs chrout_done_unknown_device // not a supported device
 chrout_iec:
@@ -38,19 +38,19 @@ chrout_iec:
 	jsr JCIOUT
 	bcc chrout_done
-	;; FALLTROUGH
+	// FALLTROUGH
 chrout_done_fail:
 	jsr show_cursor_if_enabled
 	plp
-	;; Restore X and Y
+	// Restore X and Y
 	pla
 	tay
 	pla
 	tax
-	sec ; indicate failure
+	sec // indicate failure
 	rts
 chrout_done_unknown_device:
@@ -58,13 +58,13 @@ chrout_done_unknown_device:
 	plp
-	;; Restore X and Y
+	// Restore X and Y
 	pla
 	tay
 	pla
 	tax
-	;; End wioth error
+	// End wioth error
 	jmp lvs_device_not_found_error
 chrout_done:
@@ -72,43 +72,43 @@ chrout_done:
 	plp
-	;; Restore X and Y
+	// Restore X and Y
 	pla
 	tay
 	pla
 	tax
 	lda last_printed_character_ascii
-	clc ; indicate success
+	clc // indicate success
 	rts
 chrout_screen:
-	;; Crude implementation of character output	
+	// Crude implementation of character output	
-	sei ;; XXX why do we need to disable interrupts?
+	sei // XXX why do we need to disable interrupts?
 	jsr hide_cursor_if_visible
 	lda last_printed_character_ascii
 	tax
-	;; Check for special characters
+	// Check for special characters
 	cmp #$00
 	bne not_00
 	jmp chrout_done
 not_00:
-	;; Linefeed (simply ignored)
+	// Linefeed (simply ignored)
-	;; Trivia: BASIC does CRLF with READY. prompt
+	// Trivia: BASIC does CRLF with READY. prompt
 	cmp #$0a
 	bne not_0a
 	jmp chrout_done
 not_0a:
-	;; Carriage return
+	// Carriage return
 	cmp #$0d
 	bne not_0d
-	;; RETURN clears quote and insert modes
+	// RETURN clears quote and insert modes
 	lda #$00
 	sta quote_mode_flag
 	sta insert_mode
@@ -118,9 +118,9 @@ not_0d:
 	cmp #$94
 	bne not_94
-	;; Insert (shift-DELETE)
+	// Insert (shift-DELETE)
-	;; Abort if line already max length, ie 79th char is not a space
+	// Abort if line already max length, ie 79th char is not a space
 	jsr get_current_line_logical_length
 	cmp #79
 	bne definitely_not_too_long
@@ -129,11 +129,11 @@ not_0d:
 	cmp #$20
 	beq definitely_not_too_long
-	;; Line is too long to extend
+	// Line is too long to extend
 	jmp chrout_done
 definitely_not_too_long:
-	;; Work out if line needs to be expanded, and if so expand it
+	// Work out if line needs to be expanded, and if so expand it
 	ldy #39
 	lda (current_screen_line_ptr),y
 	cmp #$20
@@ -142,18 +142,18 @@ definitely_not_too_long:
 	jsr screen_grow_logical_line
 no_need_to_extend:	
-	;; Shuffle chars towards end of line
+	// Shuffle chars towards end of line
 	jsr get_current_line_logical_length
 	tay
-*
+!:
-	;; Note: While the following routine is obvious to any skilled
+	// Note: While the following routine is obvious to any skilled
-	;; in the art as the most obvious simple and efficient solution,
+	// in the art as the most obvious simple and efficient solution,
-	;; if the screen writes are before the colour writes, it results
+	// if the screen writes are before the colour writes, it results
-	;; in a relatively long verbatim stretch of bytes when compared to
+	// in a relatively long verbatim stretch of bytes when compared to
-	;; the C64 KERNAL.  Thus we have swapped the order, just to reduce
+	// the C64 KERNAL.  Thus we have swapped the order, just to reduce
-	;; the potential for any argument of copyright infringement, even
+	// the potential for any argument of copyright infringement, even
-	;; though we really don't believe that the routine can be copyrighted
+	// though we really don't believe that the routine can be copyrighted
-	;; due to the lack of creativity.
+	// due to the lack of creativity.
 	dey
 	lda (current_screen_line_colour_ptr),y
 	iny
@@ -165,36 +165,36 @@ no_need_to_extend:
 	dey
 	cpy current_screen_x
-	bne -
+	bne !-
-	;; Increase insert mode count (which causes quote-mode like behaviour)
+	// Increase insert mode count (which causes quote-mode like behaviour)
 	inc insert_mode
-	;; Put space in the inserted gap
+	// Put space in the inserted gap
 	lda #$20
 	sta (current_screen_line_ptr),y
 	jmp chrout_done
 not_94:	
-	;; DELETE in insert mode embeds control character
+	// DELETE in insert mode embeds control character
 	ldx insert_mode
 	bne not_14
 	cmp #$14
 	bne not_14
-	;; Delete
+	// Delete
 	ldx current_screen_x
 	bne delete_non_zero_column
 delete_at_column_0:
 	ldy current_screen_y
 	bne not_row_0
-	;; delete from row 0, col 0 does nothing
+	// delete from row 0, col 0 does nothing
 	jmp chrout_done
 not_row_0:
-	;; Column 0 delete just moves us to the end of the
+	// Column 0 delete just moves us to the end of the
-	;; previous line, without actually deleting anything
+	// previous line, without actually deleting anything
 	dec current_screen_y
 	jsr get_current_line_logical_length
 	lda logical_line_length
@@ -204,13 +204,13 @@ not_row_0:
 	jmp chrout_done
 delete_non_zero_column:
-	;; Copy rest of line down
+	// Copy rest of line down
 	jsr get_current_line_logical_length
 	ldy current_screen_x
 	cpy logical_line_length
 	beq done_delete
 	dey
-*
+!:
 	iny
 	lda (current_screen_line_ptr),y
 	dey
@@ -221,9 +221,9 @@ delete_non_zero_column:
 	sta (current_screen_line_colour_ptr),y
 	iny
 	cpy logical_line_length
-	bne -
+	bne !-
-	;; Clear char at end of line
+	// Clear char at end of line
 	jsr get_current_line_logical_length
 	tay
 	lda #$20
@@ -234,7 +234,7 @@ done_delete:
 	jmp chrout_done	
 not_14:
-	;; Check for quote mode
+	// Check for quote mode
 	ldx quote_mode_flag
 	bne is_quote_mode
 	ldx insert_mode
@@ -242,51 +242,51 @@ not_14:
 	jmp not_quote_mode
 is_quote_mode:	
-	;; Is it a control code?
+	// Is it a control code?
-	;; control codes are $00-$1f and $80-$9f
+	// control codes are $00-$1f and $80-$9f
-	;; (from reading C64 PRG p379-381)
+	// (from reading C64 PRG p379-381)
-	;; so we can just check if bits 5 or 6 are set, and if so,
+	// so we can just check if bits 5 or 6 are set, and if so,
-	;; then it isn't a control character.
+	// then it isn't a control character.
 	pha
 	and #$60
-	bne +
+	bne !+
-	;; Yes, a control code in quote mode means we display it as a reverse character
+	// Yes, a control code in quote mode means we display it as a reverse character
 	pla
-	;; Low control codes are just +$80
+	// Low control codes are just +$80
 	clc
 	adc #$80
-	;; If it overflowed, then it is a high control code,
+	// If it overflowed, then it is a high control code,
-	;; so we need to make it be $80 + $40 + char
+	// so we need to make it be $80 + $40 + char
-	;; as we will have flipped back to just $00 + char, we should
+	// as we will have flipped back to just $00 + char, we should
-	;; now add $c0 if C is set from overflow
+	// now add $c0 if C is set from overflow
 	bcc low_ctrl_char
-	adc #$bf 		; C=1, so adding $BF + C = add $C0
+	adc #$bf 		// C=1, so adding $BF + C = add $C0
 low_ctrl_char:	
 	jmp output_literal_char
-*
+!:
 	pla
 not_quote_mode:
-	;; Check for colours
+	// Check for colours
 	ldx #$f
 colour_check_loop:	
 	cmp colour_codes,x
-	bne +
+	bne !+
 	stx text_colour
 	jmp chrout_done
-	* dex
+!:	dex
 	bpl colour_check_loop
-	;; Compute's Mapping the 64 p38
+	// Compute's Mapping the 64 p38
 	cmp #$12
 	bne not_12
 	lda #$80
 	sta reverse_video_flag
 	jmp chrout_done
 not_12:
-	;; Compute's Mapping the 64 p 38	
+	// Compute's Mapping the 64 p 38	
 	cmp #$92
 	bne not_92
 	lda #$00
@@ -294,17 +294,17 @@ not_12:
 	jmp chrout_done
 not_92:
-	;; Check for cursor movement keys
+	// Check for cursor movement keys
 	cmp #$11
 	bne not_11
 	lda current_screen_x
 	clc
 	adc #40
 	sta current_screen_x
-	;; We need to advance the pointer manually, as normalising
+	// We need to advance the pointer manually, as normalising
-	;; now will break things. The pointer update is required
+	// now will break things. The pointer update is required
-	;; so that we can tell if we really are on the bottom phys
+	// so that we can tell if we really are on the bottom phys
-	;; screen line or not
+	// screen line or not
 	jsr scroll_up_if_on_last_line
 	jsr calculate_screen_line_pointer
 	jmp chrout_done
@@ -331,7 +331,7 @@ not_91:
 	jmp chrout_done
 not_9d:
-	;; Home cursor
+	// Home cursor
 	cmp #$13
 	bne not_13
 	lda #0
@@ -341,7 +341,7 @@ not_9d:
 	jmp chrout_done
 not_13:	
-	;; Clear screen
+	// Clear screen
 	cmp #$93
 	bne not_clearscreen
 	jsr clear_screen
@@ -349,41 +349,41 @@ not_13:
 not_clearscreen:
-	;;  Convert PETSCII to screen code
+	//  Convert PETSCII to screen code
-	;; Don't print other control codes
+	// Don't print other control codes
 	cmp #$1f
-	bcs +
+	bcs !+
 	jmp chrout_done
-*
+!:
-	;; Codes $C0-$DF become $40-$5F
+	// Codes $C0-$DF become $40-$5F
-	;; But 
+	// But 
 	cmp #$e0
-	bcs +
+	bcs !+
 	cmp #$c0
-	bcc +
+	bcc !+
 	and #$7f
 	jmp not_high_char
-*
+!:
-	;; Range $20-$3F is unchanged
+	// Range $20-$3F is unchanged
 	cmp #$40
 	bcc not_high_char
-	;; Unshifted letters and symbols from $40-$5F
+	// Unshifted letters and symbols from $40-$5F
-	;; all end up being -$40
+	// all end up being -$40
-	;; (C64 PRG p376)
+	// (C64 PRG p376)
-	;; But anything >= $80 needs to be -$40
+	// But anything >= $80 needs to be -$40
-	;; (C64 PRG p380-381)
+	// (C64 PRG p380-381)
-	;; And bit 7 should be cleared, only to be
+	// And bit 7 should be cleared, only to be
-	;; set by reverse video
+	// set by reverse video
 	sec
 	sbc #$40
-	;; Fix shifted chars by adding $20 again
+	// Fix shifted chars by adding $20 again
 	cmp #$20
 	bcc not_high_char
 	cmp #$40
@@ -397,45 +397,45 @@ chrout_l1:
 output_literal_char:
-	;; Write normal character on the screen
+	// Write normal character on the screen
 	pha
 	ldy current_screen_x
-	ora reverse_video_flag	; Compute's Mapping the 64  p38
+	ora reverse_video_flag	// Compute's Mapping the 64  p38
 	sta (current_screen_line_ptr),y
-	;; Decrement number of chars waiting to be inserted
+	// Decrement number of chars waiting to be inserted
 	lda insert_mode
-	beq +
+	beq !+
 	dec insert_mode
-*	
+!:	
 	pla
 	cmp #$22
 	bne not_quote
-	;;  Toggle quote flag if required
+	//  Toggle quote flag if required
 	lda quote_mode_flag
 	eor #$80
 	sta quote_mode_flag
 not_quote:
-	;; Set colour
+	// Set colour
 	lda text_colour
 	sta (current_screen_line_colour_ptr),y
-	;; Advance the column, and scroll screen down if we need
+	// Advance the column, and scroll screen down if we need
-	;; to insert a 2nd line in this logical line.
+	// to insert a 2nd line in this logical line.
-	;; (eg Compute's Mapping the 64 p41)
+	// (eg Compute's Mapping the 64 p41)
 	ldx current_screen_y
 	iny
 	sty current_screen_x
 	cpy #40
-	bne +
+	bne !+
 	jsr screen_grow_logical_line
 	ldy current_screen_x
-*
+!:
 	cpy #80
 	bcc no_screen_advance_to_next_line
 	lda #0
@@ -446,35 +446,35 @@ no_screen_advance_to_next_line:
 screen_grow_logical_line:
 	ldy current_screen_y
-	;; Don't grow line if it is already grown
+	// Don't grow line if it is already grown
 	lda screen_line_link_table,y
-	bpl +
+	bpl !+
 	jmp done_grow_line
-*
+!:
 	lda #$80
 	sta screen_line_link_table,y
-	;; Now make space for the extra line added.
+	// Now make space for the extra line added.
-	;; If we are on the last physical line of the screen,
+	// If we are on the last physical line of the screen,
-	;; Then we need to scroll the screen up
+	// Then we need to scroll the screen up
 	jsr scroll_up_if_on_last_line
-	;; Scroll screen down to make space
+	// Scroll screen down to make space
-	;; As we are scrolling down, we start from the end,
+	// As we are scrolling down, we start from the end,
-	;; and work backwards.  We can't be as simple and efficient
+	// and work backwards.  We can't be as simple and efficient
-	;; here as we are for scrolling up, because we don't know
+	// here as we are for scrolling up, because we don't know
-	;; how much must be scrolled.
+	// how much must be scrolled.
-	;; Simple solution is to work out how many physical lines
+	// Simple solution is to work out how many physical lines
-	;; need shifting down, and then move lines at a time after
+	// need shifting down, and then move lines at a time after
-	;; initialising the pointers to the end area of the screen.
+	// initialising the pointers to the end area of the screen.
 	ldx #25-2
 	ldy #0
 count_rows_loop:
 	dex
 	lda screen_line_link_table,y
-	bpl +
+	bpl !+
 	dex
-*	iny
+!:	iny
 	cpy current_screen_y
 	bne count_rows_loop
@@ -482,14 +482,14 @@ count_rows_loop:
 	beq no_copy_down
 	bmi no_copy_down
-	;; Set pointers to end of screen line, and one line
+	// Set pointers to end of screen line, and one line
-	;; above.  (It is always one physical line, because
+	// above.  (It is always one physical line, because
-	;; this can only happen when expanding a line from 40 to
+	// this can only happen when expanding a line from 40 to
-	;; 80 characters).
+	// 80 characters).
-	;; XXX - This is not very efficient, and longer than it
+	// XXX - This is not very efficient, and longer than it
-	;; needs to be. Better would be to work out size to
+	// needs to be. Better would be to work out size to
-	;; copy, and count it down in a pointer somewhere, so
+	// copy, and count it down in a pointer somewhere, so
-	;; that loop iteration logic is simpler.
+	// that loop iteration logic is simpler.
 	lda HIBASE
 	clc
 	adc #3
@@ -502,7 +502,7 @@ count_rows_loop:
 	lda #<$03C0
 	sta current_screen_line_ptr+0
 	sta current_screen_line_colour_ptr+0
-	;;  souce address is line above
+	//  souce address is line above
 	sec
 	sbc #40
 	sta load_or_scroll_temp_pointer+0
@@ -518,11 +518,11 @@ cl_inner:
 	dey
 	bpl cl_inner
-	;; Decrement all pointers by 40
+	// Decrement all pointers by 40
-	;; Low bytes are in common pairs
+	// Low bytes are in common pairs
-	;; Old source is new destination
+	// Old source is new destination
-	;; Use different registers to minimise byte similarity with C64 KERNAl
+	// Use different registers to minimise byte similarity with C64 KERNAl
 	ldy load_or_scroll_temp_pointer+1
 	sty current_screen_line_ptr+1
 	lda load_save_verify_end_address+1
@@ -531,7 +531,7 @@ cl_inner:
 	sty current_screen_line_ptr+0
 	sty current_screen_line_colour_ptr+0
-	;; Decrementing source pointers
+	// Decrementing source pointers
 	lda load_or_scroll_temp_pointer+0
 	sec
 	sbc #<40
@@ -540,7 +540,7 @@ cl_inner:
 	lda load_or_scroll_temp_pointer+1
 	sbc #>40
 	sta load_or_scroll_temp_pointer+1
-	;; convert to screen equivalent
+	// convert to screen equivalent
 	sec
 	sbc HIBASE
 	clc
@@ -553,16 +553,16 @@ cl_inner:
 no_copy_down:
 	jsr calculate_screen_line_pointer
-	;; Erase newly inserted line
+	// Erase newly inserted line
 	ldy #79
-	*
+!:
 	lda text_colour
 	sta (current_screen_line_colour_ptr),y
 	lda #$20
 	sta (current_screen_line_ptr),y
 	dey
 	cpy #40
-	bne -
+	bne !-
 	rts
@@ -572,9 +572,9 @@ not_last_line:
 scroll_up_if_on_last_line:
-	;; Colour RAM is always in fixed place, so is easiest
+	// Colour RAM is always in fixed place, so is easiest
-	;; to use to check if we are on the last line.
+	// to use to check if we are on the last line.
-	;; The last line is at $D800 + 24*40 = $DBC0
+	// The last line is at $D800 + 24*40 = $DBC0
 	lda current_screen_line_colour_ptr+1
 	cmp #>$DBC0
 	bne not_last_line
@@ -593,13 +593,13 @@ is_last_line:
 	dec current_screen_y
-	;; FALL THROUGH
+	// FALL THROUGH
 scroll_screen_up:	
-	;; Now scroll the whole screen up either one or two lines
+	// Now scroll the whole screen up either one or two lines
-	;; based on whether the first screen line is linked or not.
+	// based on whether the first screen line is linked or not.
-	;; Get pointers to start of screen + colour RAM
+	// Get pointers to start of screen + colour RAM
 	lda HIBASE
 	sta current_screen_line_ptr+1
 	sta load_or_scroll_temp_pointer+1
@@ -610,17 +610,17 @@ scroll_screen_up:
 	sta current_screen_line_ptr+0
 	sta current_screen_line_colour_ptr+0
-	;;  Get pointers to screen/colour RAM source
+	//  Get pointers to screen/colour RAM source
 	lda screen_line_link_table+0
-	bmi +
+	bmi !+
 	lda #40
-	.byte $2C 		; BIT $nnnn to skip next instruction
+	.byte $2C 		// BIT $nnnn to skip next instruction
-	*
+!:
 	lda #80
 	sta load_or_scroll_temp_pointer+0
 	sta load_save_verify_end_address+0
-	;;  Copy first three pages
+	//  Copy first three pages
 	ldy #$00
 	ldx #3
 scroll_copy_loop:
@@ -639,9 +639,9 @@ scroll_copy_loop:
 	dex
 	bne scroll_copy_loop
-	;; Copy last partial page
+	// Copy last partial page
-	;; We need to copy 1000-(3*256)-line length
+	// We need to copy 1000-(3*256)-line length
-	;; = 232 - line length
+	// = 232 - line length
 	lda load_or_scroll_temp_pointer+0
 	lda #232
 	sec
@@ -656,7 +656,7 @@ scroll_copy_loop2:
 	dex
 	bne scroll_copy_loop2
-	;; Fill in scrolled up area
+	// Fill in scrolled up area
 	ldx load_or_scroll_temp_pointer+0
 scroll_copy_loop3:
 	lda text_colour
@@ -667,7 +667,7 @@ scroll_copy_loop3:
 	dex
 	bne scroll_copy_loop3
-	;; Shift line linkage list
+	// Shift line linkage list
 	ldy #0
 	ldx #24
 link_copy:
@@ -676,10 +676,10 @@ link_copy:
 	iny
 	dex
 	bne link_copy
-	;; Clear line link flag of last line
+	// Clear line link flag of last line
 	stx screen_line_link_table+24
-	;; Restore correct line pointers
+	// Restore correct line pointers
 	jsr calculate_screen_line_pointer
 	rts
@@ -689,7 +689,7 @@ get_current_line_logical_length:
 	lda screen_line_link_table,y
 	bpl line_not_linked_del
 	lda #79
-	.byte $2c 		; BIT absolute mode, which we use to skip the next two instruction bytes
+	.byte $2c 		// BIT absolute mode, which we use to skip the next two instruction bytes
 line_not_linked_del:
 	lda #39
 	sta logical_line_length
@@ -697,21 +697,21 @@ line_not_linked_del:
 screen_advance_to_next_line:
-	;; jsr hide_cursor_if_visible
+	// jsr hide_cursor_if_visible
-	;;  Go to start of line
+	//  Go to start of line
 	lda #0
 	sta current_screen_x
-	;;  Advance line number
+	//  Advance line number
 	ldy current_screen_y
-	;; Do quick fix to line pointer to work out if it is off
+	// Do quick fix to line pointer to work out if it is off
-	;; the bottom of the screen.
+	// the bottom of the screen.
 	ldx #40
 	lda screen_line_link_table,y
-	bmi +
+	bmi !+
 	.byte $2c
-*	ldx #80
+!:	ldx #80
 	txa
 	clc
 	adc current_screen_line_ptr+0
@@ -722,22 +722,22 @@ screen_advance_to_next_line:
 	inc current_screen_y
-	;; Check if it will trigger scrolling
+	// Check if it will trigger scrolling
-	;; Work out if we have gone off the bottom of the screen?
+	// Work out if we have gone off the bottom of the screen?
-	;; 1040 > 1024, so if high byte of screen pointer is >= (HIBASE+4),
+	// 1040 > 1024, so if high byte of screen pointer is >= (HIBASE+4),
-	;; then we are off the bottom of the screen
+	// then we are off the bottom of the screen
 	lda current_screen_line_ptr+1
 	sec
 	sbc HIBASE
 	cmp #3
-	bcc +
+	bcc !+
 	lda current_screen_line_ptr+0
 	cmp #$e7
-	bcc +
+	bcc !+
-	;; Off the bottom of the screen
+	// Off the bottom of the screen
 	jsr scroll_screen_up	
-*
+!:
 	jsr calculate_screen_line_pointer
@@ -751,38 +751,38 @@ add_40_to_screen_x:
 	rts
 normalise_screen_x_y:	
-	;; Normalise X and Y values
+	// Normalise X and Y values
-	;; If X < 0, then make X = X + 40 (or 80, if previous line is linked)
+	// If X < 0, then make X = X + 40 (or 80, if previous line is linked)
-*	lda current_screen_x
+!:	lda current_screen_x
 	bpl x_not_negative
 	dec current_screen_y
-	;; Check that we didn't go backwards off the top of the screen
+	// Check that we didn't go backwards off the top of the screen
-	bpl +
+	bpl !+
 	lda #0
 	sta current_screen_y
-*	jsr add_40_to_screen_x
+!:	jsr add_40_to_screen_x
-	;; Check if line is linked, if so, add 40 again
+	// Check if line is linked, if so, add 40 again
 	ldy current_screen_y
 	lda screen_line_link_table,y
-	bpl +
+	bpl !+
 	jsr add_40_to_screen_x
-*
+!:
 x_not_negative:
-	;; Work out if X is too big
+	// Work out if X is too big
 	ldy current_screen_y
 	lda screen_line_link_table,y
-	bpl +
+	bpl !+
 	lda #79
-	.byte $2C 		; BIT $nnnn, used to skip next instruction
+	.byte $2C 		// BIT $nnnn, used to skip next instruction
-*	lda #39
+!:	lda #39
 	cmp current_screen_x
 	bcs x_not_too_big
-	;; X value is too big, so subtract 40 and increment Y
+	// X value is too big, so subtract 40 and increment Y
 	lda current_screen_x
 	sec
 	sbc #40
@@ -791,28 +791,28 @@ x_not_negative:
 x_not_too_big:
-	;; Make sure Y isn't negative
+	// Make sure Y isn't negative
 	lda current_screen_y
-	bpl +
+	bpl !+
 	lda #0
 	sta current_screen_y
-*
+!:
-	;; Make sure Y isn't too large for absolute size of
+	// Make sure Y isn't too large for absolute size of
-	;; screen
+	// screen
 	cmp #24
-	bcc +
+	bcc !+
 	lda #24
 	sta current_screen_y
-*
+!:
-	;; Make sure Y isn't too much for the screen, taking
+	// Make sure Y isn't too much for the screen, taking
-	;; into account the line link table
+	// into account the line link table
-	ldy #24 		; max allowable line
+	ldy #24 		// max allowable line
 	ldx #0
 link_count_loop:
 	lda screen_line_link_table,x
-	bpl +
+	bpl !+
 	dey
-*	inx
+!:	inx
 	cpx #25
 	bne link_count_loop
 	tya
@@ -826,29 +826,29 @@ y_ok:
 calculate_screen_line_pointer:
 	jsr normalise_screen_x_y
-	;;  Reset pointer to start of screen
+	//  Reset pointer to start of screen
 	lda HIBASE
 	sta current_screen_line_ptr+1
 	lda #0
 	sta current_screen_line_ptr+0
-	;; Add 40 for every line, or 80 if the lines are linked
+	// Add 40 for every line, or 80 if the lines are linked
 	ldx current_screen_y
-*
+!:
-	;; Stop if we have counted enough lines
+	// Stop if we have counted enough lines
-	beq +
+	beq !+
-	;; Add 40 or 80 based on whether the line is linked
+	// Add 40 or 80 based on whether the line is linked
-	;; or not.
+	// or not.
 	ldy #40
-	;; -1 offset is because we count down from N to 1, not
+	// -1 offset is because we count down from N to 1, not
-	;; N-1 to 0.
+	// N-1 to 0.
 	lda screen_line_link_table-1,x
 	bpl cslp_l1
 	ldy #80
 cslp_l1:
-	;; Add computed line length to pointer value
+	// Add computed line length to pointer value
 	tya
 	clc
 	adc current_screen_line_ptr+0
@@ -857,15 +857,15 @@ cslp_l1:
 	adc #0
 	sta current_screen_line_ptr+1
-	;; Loop back to next line
+	// Loop back to next line
 	dex
-	jmp -
+	jmp !-
-*
+!:
-	;; FALL THROUGH
+	// FALL THROUGH
 update_colour_line_pointer:	
-	;; Now setup pointer to colour RAM
+	// Now setup pointer to colour RAM
 	lda current_screen_line_ptr+0
 	sta current_screen_line_colour_ptr+0
 	lda current_screen_line_ptr+1
@@ -896,6 +896,6 @@ advance_screen_pointer_40_bytes:
 	jmp update_colour_line_pointer
 colour_codes:
-	;; CHR$ codes for the 16 colours
+	// CHR$ codes for the 16 colours
 	.byte 144,5,28,159,156,30,31,158
 	.byte 129,149,150,151,152,153,154,155
@@ -1,24 +1,24 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 280
+// - [RG64] C64 Programmer's Reference Guide   - page 280
-;; - [CM64] Compute's Mapping the Commodore 64 - page 242
+// - [CM64] Compute's Mapping the Commodore 64 - page 242
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
 cint_real:
-	;; According to [CM64], this routine checks for PAL/NTSC. It's definitely not done
+	// According to [CM64], this routine checks for PAL/NTSC. It's definitely not done
-	;; within the 'BRK' part, this can be easily checked - POKE something
+	// within the 'BRK' part, this can be easily checked - POKE something
-	;; to address 678 on a real C64, press STOP+RESTORE, the value won't change
+	// to address 678 on a real C64, press STOP+RESTORE, the value won't change
-	;; Detect video system (PAL/NTSC), use Graham's method, as it's short and reliable
+	// Detect video system (PAL/NTSC), use Graham's method, as it's short and reliable
-	;; see here: https://codebase64.org/doku.php?id=base:detect_pal_ntsc
+	// see here: https://codebase64.org/doku.php?id=base:detect_pal_ntsc
-	lda #$C8 ; preparation, as the VIC might be uninitialized
+	lda #$C8 // preparation, as the VIC might be uninitialized
 	sta VIC_SCROLX
 cint_w0:
@@ -28,18 +28,18 @@ cint_w1:
 	beq cint_w1
 	bmi cint_w0
-	;; Result in A, if no interrupt happened during the test:
+	// Result in A, if no interrupt happened during the test:
-	;; #$37 -> 312 rasterlines, PAL,  VIC 6569
+	// #$37 -> 312 rasterlines, PAL,  VIC 6569
-	;; #$06 -> 263 rasterlines, NTSC, VIC 6567R8
+	// #$06 -> 263 rasterlines, NTSC, VIC 6567R8
-	;; #$05 -> 262 rasterlines, NTSC, VIC 6567R56A
+	// #$05 -> 262 rasterlines, NTSC, VIC 6567R56A
 	cmp #$07
 	bcs cint_pal
 cint_ntsc:
-	;; NTSC C64 (https://codebase64.org/doku.php?id=base:cpu_clocking),
+	// NTSC C64 (https://codebase64.org/doku.php?id=base:cpu_clocking),
-	;; is clocked at 1.022727 MHz, so that 1/60s is 17045 CPU cycles
+	// is clocked at 1.022727 MHz, so that 1/60s is 17045 CPU cycles
 	ldy #<17045
 	ldx #>17045
@@ -48,51 +48,51 @@ cint_ntsc:
 	stx CIA1_TIMAHI
 	lda #$00
-	beq +
+	beq !+
 cint_pal:
 	lda #$01
-*
+!:
 	sta PALNTSC
-cint_brk: ; entry for BRK and STOP+RESTORE - XXX, where should it start?
+cint_brk: // entry for BRK and STOP+RESTORE - XXX, where should it start?
 	jsr setup_vicii
-	;; Initialise cursor blink flags  (Compute's Mapping the 64 p215)
+	// Initialise cursor blink flags  (Compute's Mapping the 64 p215)
 	lda #$00
 	sta cursor_blink_disable
-	;; Set keyboard decode vector  (Compute's Mapping the 64 p215)
+	// Set keyboard decode vector  (Compute's Mapping the 64 p215)
-	;; Set initial variables for our improved keyboard scan routine
+	// Set initial variables for our improved keyboard scan routine
-	lda #$ff
+	lda #$FF
 	ldx #6
-*	sta BufferOld,x
+!:	sta BufferOld,x
 	dex
-	bpl -
+	bpl !-
 	sta BufferQuantity
-	;; Set key repeat delay (Compute's Mapping the 64 p215)
+	// Set key repeat delay (Compute's Mapping the 64 p215)
-	;; Making some numbers up here: Repeat every ~1/10th sec
+	// Making some numbers up here: Repeat every ~1/10th sec
-	;; But require key to be held for ~1/3sec before
+	// But require key to be held for ~1/3sec before
-        ;; repeating (Compute's Mapping the 64 p58)
+	// repeating (Compute's Mapping the 64 p58)
-	ldx #22-2 		; Fudge factor to match speed
+	ldx #22-2 		// Fudge factor to match speed
 	stx key_first_repeat_delay
-	;; Set current colour for text (Compute's Mapping the 64 p215)
+	// Set current colour for text (Compute's Mapping the 64 p215)
-	ldx #$01     ; default is light blue ($0E), but we use a different one
+	ldx #$01     // default is light blue ($0E), but we use a different one
 	stx text_colour
-	;; Set maximum keyboard buffer size (Compute's Mapping the 64 p215)
+	// Set maximum keyboard buffer size (Compute's Mapping the 64 p215)
 	ldx #10
 	stx key_buffer_size
-	;; Put non-zero value in enable_case_switch
+	// Put non-zero value in enable_case_switch
 	stx enable_case_switch
-	;; Set default I/O devices (see SCINIT description at http://sta.c64.org/cbm64krnfunc.html)
+	// Set default I/O devices (see SCINIT description at http://sta.c64.org/cbm64krnfunc.html)
 	jsr clrchn_reset
-	;; Fallthrough/jump to screen clear routine (Compute's Mapping the 64 p215)
+	// Fallthrough/jump to screen clear routine (Compute's Mapping the 64 p215)
 	jmp clear_screen
@@ -1,37 +1,37 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 279/280
+// - [RG64] C64 Programmer's Reference Guide   - page 279/280
-;; - [CM64] Compute's Mapping the Commodore 64 - page 224
+// - [CM64] Compute's Mapping the Commodore 64 - page 224
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .X, .Y
+// CPU registers that has to be preserved (see [RG64]): .X, .Y
-;;
+//
-ciout:
+CIOUT:
 	pha
 	lda C3PO
 	bne ciout_send_byte
-	;; Nothing to send - set buffer as valid, store byte there
+	// Nothing to send - set buffer as valid, store byte there
 	inc C3PO
-	;; Clear carry flag to indicate success
+	// Clear carry flag to indicate success
 	clc
 ciout_store_in_buffer:
-	;; Store in the buffer data to be sent next, return
+	// Store in the buffer data to be sent next, return
 	pla
 	sta BSOUR
 	rts
 ciout_send_byte:
-	clc ; don't send with EOI
+	clc // don't send with EOI
 	jsr iec_tx_byte
-	inc C3PO ; iec_tx_byte sets it to 0, but we still have something to send
+	inc C3PO // iec_tx_byte sets it to 0, but we still have something to send
 	jmp ciout_store_in_buffer
@@ -1,38 +1,38 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 281
+// - [RG64] C64 Programmer's Reference Guide   - page 281
-;; - [CM64] Compute's Mapping the Commodore 64 - page 230
+// - [CM64] Compute's Mapping the Commodore 64 - page 230
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
 clall_real:
-	;; Store .Y register
+	// Store .Y register
 	tya
 	pha
-	;; Original routine probably just sets LDTND to 0, but this is not really safe,
+	// Original routine probably just sets LDTND to 0, but this is not really safe,
-	;; so we actually close all the channels; at least IDE64 does the same for
+	// so we actually close all the channels; at least IDE64 does the same for
-	;; it's channels, see CLALL description in the IDE64 User's Guide
+	// it's channels, see CLALL description in the IDE64 User's Guide
-*
+!:
 	ldy LDTND
-	beq +
+	beq !+
 	dey
 	lda LAT, y
 	jsr JCLOSE
-	jmp -
+	jmp !-
-*
+!:
-	;; Restore .Y register
+	// Restore .Y register
 	pla
 	tay
-	;; 'C64 Programmers Reference Guide', page 281, claims it calls CLRCHN too
+	// 'C64 Programmers Reference Guide', page 281, claims it calls CLRCHN too
-	jsr clrchn
+	jsr CLRCHN
-	;; Not sure whether original Kernal does so, but it seems sane to also clear possible errors
+	// Not sure whether original Kernal does so, but it seems sane to also clear possible errors
 	jmp kernalstatus_reset
@@ -1,23 +1,23 @@
-;; Common ppart of CLOSE and LOAD routines
+// Common ppart of CLOSE and LOAD routines
 close_load:
 	tax
-	;; Command drive to stop talking and to close the file
+	// Command drive to stop talking and to close the file
-	jsr untlk
+	jsr UNTLK
 	txa
-	jsr listen
+	jsr LISTEN
-	lda #$E0 ; CLOSE command
+	lda #$E0 // CLOSE command
 	sta IEC_TMP2
 	jsr iec_tx_command
 	jsr iec_tx_command_finalize
-	;; Tell drive to unlisten
+	// Tell drive to unlisten
-	jsr unlsn
+	jsr UNLSN
 	rts
@@ -1,35 +1,35 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 282
+// - [RG64] C64 Programmer's Reference Guide   - page 282
-;; - [CM64] Compute's Mapping the Commodore 64 - page 230
+// - [CM64] Compute's Mapping the Commodore 64 - page 230
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
 clrchn_real:
-	;; Handle IEC input device
+	// Handle IEC input device
 	lda DFLTN
 	jsr iec_check_devnum
-	bcs +
+	bcs !+
-	;; Previous device was IEC one - send UNTALK first
+	// Previous device was IEC one - send UNTALK first
-	jsr untlk
+	jsr UNTLK
-*
+!:
-	;; Restore output device to default
+	// Restore output device to default
 	lda DFLTO
 	jsr iec_check_devnum
-	bcs +
+	bcs !+
-	;; Handle IEC output device
+	// Handle IEC output device
-	jsr unlsn
+	jsr UNLSN
-*
+!:
-clrchn_reset: ;; entry needed by CHRIN
+clrchn_reset: // entry needed by CHRIN
-	;; Set input device number to keyboard
+	// Set input device number to keyboard
 	lda #$00
 	sta DFLTN
-	;; Set output device number to screen
+	// Set output device number to screen
 	lda #$03
 	sta DFLTO
@@ -1,10 +1,10 @@
-	;; Clear screen and initialise line link table
+// Clear screen and initialise line link table
-	;; (Compute's Mapping the 64 p215-216)
+// (Compute's Mapping the 64 p215-216)
 clear_screen:
-	;; Clear line link table 
+	// Clear line link table 
-	;; (Compute's Mapping the 64 p215)
+	// (Compute's Mapping the 64 p215)
 	lda #$00
 	ldy #24
@@ -13,27 +13,27 @@ clearscreen_l1:
 	dey
 	bpl clearscreen_l1
-	;; Y now = #$FF
+	// Y now = #$FF
-	;; Clear screen RAM.
+	// Clear screen RAM.
-	;; We should do this at HIBASE, which annoyingly
+	// We should do this at HIBASE, which annoyingly
-	;; is no ZP, so we need to make a vector
+	// is no ZP, so we need to make a vector
-	;; (Compute's Mapping the 64 p216)
+	// (Compute's Mapping the 64 p216)
-	;; Get pointer to the screen into current_screen_line_ptr
+	// Get pointer to the screen into current_screen_line_ptr
-	;; as it is the first appropriate place for it found when
+	// as it is the first appropriate place for it found when
-	;; searching through the ZP allocations listed in
+	// searching through the ZP allocations listed in
-	;; Compute's Mapping the 64
+	// Compute's Mapping the 64
 	sta current_screen_line_ptr+0
-	lda hibase
+	lda HIBASE
 	sta current_screen_line_ptr+1
-	ldx #$03		; countdown for pages to update
+	ldx #$03		// countdown for pages to update
-	iny 			; Y now = #$00
+	iny 			// Y now = #$00
-	lda #$20		; space character
+	lda #$20		// space character
 clearscreen_l2:
 	sta (current_screen_line_ptr),y
 	iny
 	bne clearscreen_l2
-	;; To draw only 1000 bytes, add 250 to address each time
+	// To draw only 1000 bytes, add 250 to address each time
 	lda current_screen_line_ptr
 	clc
 	adc #<250
@@ -41,20 +41,20 @@ clearscreen_l2:
 	lda current_screen_line_ptr+1
 	adc #>250
 	sta current_screen_line_ptr+1
-	lda #$20		; get space character again
+	lda #$20		// get space character again
 	dex
 	bpl clearscreen_l2
-	;; Clear colour RAM
+	// Clear colour RAM
-	;; (Compute's Mapping the 64 p216)
+	// (Compute's Mapping the 64 p216)
 	lda text_colour
 clearscreen_l3:	
 	sta $d800,y
 	sta $d900,y
 	sta $da00,y
-	sta $db00-24,y    	; so we only erase 1000 bytes
+	sta $db00-24,y    	// so we only erase 1000 bytes
 	iny
 	bne clearscreen_l3
-	;; (Compute's Mapping the 64 p216)
+	// (Compute's Mapping the 64 p216)
 	jmp home_cursor
@@ -1,20 +1,20 @@
 setup_vicii:
-	;; Set up default IO values (Compute's Mapping the 64 p215)
+	// Set up default IO values (Compute's Mapping the 64 p215)
-	lda #$1B    ; Enable text mode
+	lda #$1B    // Enable text mode
 	sta VIC_SCROLY
-	lda #$C8    ; 40 column etc
+	lda #$C8    // 40 column etc
 	sta VIC_SCROLX
-	;; Compute's Mapping the 64, p156
+	// Compute's Mapping the 64, p156
-	;; We use a different colour scheme of white text on all blue
+	// We use a different colour scheme of white text on all blue
 	lda #$06
 	sta VIC_EXTCOL
 	sta VIC_BGCOL0
-	;; Turn off sprites (observed hanging around after running programs and resetting)
+	// Turn off sprites (observed hanging around after running programs and resetting)
 	lda #$00
 	sta VIC_SPENA
-	;;FALLTROUGH
+	// FALLTROUGH
@@ -1,7 +1,7 @@
-;; Kernal error codes are described in 'Commodore 64 Programmer's Reference Guide', page 306
+// Kernal error codes are described in 'Commodore 64 Programmer's Reference Guide', page 306
-kernalerror_ROUTINE_TERMINATED: ; by a STOP key
+kernalerror_ROUTINE_TERMINATED: // by a STOP key
 	lda #K_ERR_ROUTINE_TERMINATED
 	sec
 	rts
@@ -56,20 +56,20 @@ kernalerror_TOP_MEM_RS232:
 	sec
 	rts
-;; Kernal status codes are described in 'Commodore 64 Programmer's Reference Guide', page 292
+// Kernal status codes are described in 'Commodore 64 Programmer's Reference Guide', page 292
 kernalstatus_reset:
 	lda #$00
 	sta IOSTATUS
 	rts
-kernalstatus_TIMEOUT_WRITE: ;; XXX detect this!
+kernalstatus_TIMEOUT_WRITE: // XXX detect this!
 	lda IOSTATUS
 	ora #K_STS_TIMEOUT_WRITE
 	sta IOSTATUS
 	rts
-kernalstatus_TIMEOUT_READ: ;; XXX detect this!
+kernalstatus_TIMEOUT_READ: // XXX detect this!
 	lda IOSTATUS
 	ora #K_STS_TIMEOUT_READ
 	sta IOSTATUS
@@ -1,27 +1,27 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 283
+// - [RG64] C64 Programmer's Reference Guide   - page 283
-;; - [CM64] Compute's Mapping the Commodore 64 - page 227/228
+// - [CM64] Compute's Mapping the Commodore 64 - page 227/228
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .X, .Y
+// CPU registers that has to be preserved (see [RG64]): .X, .Y
-;;
+//
-;; XXX currently does not preserve registers, to be fixed!
+// XXX currently does not preserve registers, to be fixed!
-getin:
+GETIN:
-	;; Wait for a key
+	// Wait for a key
 	lda keys_in_key_buffer
-	bne +
+	bne !+
-	;; Nothing in keyboard buffer to read
+	// Nothing in keyboard buffer to read
 	sec
 	lda #$00
 	rts
-*
+!:
 	lda keyboard_buffer
 	pha
@@ -1,6 +1,6 @@
-;; Our implementation is longer than the original one,
+// Our implementation is longer than the original one,
-;; placing it here would cause a collision with CHROUT
+// placing it here would cause a collision with CHROUT
-chrin:
+CHRIN:
    jmp chrin_real
@@ -1,6 +1,6 @@
-;; Our implementation is longer than the original one,
+// Our implementation is longer than the original one,
-;; placing it here would cause a collision with CHKIN
+// placing it here would cause a collision with CHKIN
-chrout:
+CHROUT:
    jmp chrout_real
@@ -1,6 +1,6 @@
-;; In our implementation CHKIN and CKOUT are closely tied,
+// In our implementation CHKIN and CKOUT are closely tied,
-;; placing it here would cause a collision
+// placing it here would cause a collision
-chkin:
+CHKIN:
    jmp chkin_real
@@ -1,6 +1,6 @@
-;; In our implementation CHKIN and CKOUT are closely tied,
+// In our implementation CHKIN and CKOUT are closely tied,
-;; placing it here would cause a collision
+// placing it here would cause a collision
-ckout:
+CKOUT:
    jmp ckout_real
@@ -1,49 +1,49 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 281/282
+// - [RG64] C64 Programmer's Reference Guide   - page 281/282
-;; - [CM64] Compute's Mapping the Commodore 64 - page 229/230
+// - [CM64] Compute's Mapping the Commodore 64 - page 229/230
-;; - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc (IEC command)
+// - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc (IEC command)
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-close:
+CLOSE:
-	;; XXX this needs more testing (opening 10 files at once, closing in various orders, etc) once the code is more mature
+	// XXX this needs more testing (opening 10 files at once, closing in various orders, etc) once the code is more mature
-	;; Find the LAT / SAT / FAT entry which LAT corresponds to A
+	// Find the LAT / SAT / FAT entry which LAT corresponds to A
 	jsr find_fls
-	bcs close_error_not_found ;; XXX can we report error in IOSTATUS here?
+	bcs close_error_not_found // XXX can we report error in IOSTATUS here?
-	;; We have the entry index in Y - check whether this is IEC device
+	// We have the entry index in Y - check whether this is IEC device
 	lda FAT, y
 	jsr iec_check_devnum
 	bcs close_remove_from_table
-	;; IEC device
+	// IEC device
-	jsr iec_tx_flush ; make sure no byte is awaiting
+	jsr iec_tx_flush // make sure no byte is awaiting
-	lda SAT, y ; get secondary address
+	lda SAT, y       // get secondary address
 	cmp #$60
-	bne +
+	bne !+
-	;; workaround for using CLOSE on reading executable - XXX is this a proper way?
+	// workaround for using CLOSE on reading executable - XXX is this a proper way?
 	jsr close_load 
 	jmp close_remove_from_table
-*
+!:
-	ora $E0 ; CLOSE command
+	ora $E0 // CLOSE command
 	sta IEC_TMP2
 	jsr iec_tx_command
 	bcs close_remove_from_table
 	jsr iec_tx_command_finalize
 close_remove_from_table:
-	;; Remove channel from the table
+	// Remove channel from the table
 	iny
 	cpy #$0A
-	bpl +
+	bpl !+
 	lda LAT, y
 	sta LAT-1, y
 	lda FAT, y
@@ -51,14 +51,14 @@ close_remove_from_table:
 	lda SAT, y
 	sta SAT-1, y
 	jmp close_remove_from_table
-*
+!:
-	;; Decrement the list size variable
+	// Decrement the list size variable
 	dec LDTND
-	clc ; report success - not sure if original CLOSE does this, but it's nevertheless a good practice
+	clc // report success - not sure if original CLOSE does this, but it's nevertheless a good practice
 	rts
 close_error_not_found:
-	sec ; report success - not sure if original CLOSE does this, but it's nevertheless a good practice
+	sec // report success - not sure if original CLOSE does this, but it's nevertheless a good practice
 	rts
@@ -1,6 +1,6 @@
-;; Our implementation is longer than the original one,
+// Our implementation is longer than the original one,
-;; placing it here would cause a collision with CLRCHN
+// placing it here would cause a collision with CLRCHN
-clall:
+CLALL:
    jmp clall_real
@@ -1,6 +1,6 @@
-;; Our implementation is longer than the original one,
+// Our implementation is longer than the original one,
-;; placing it here would cause a collision with OPEN
+// placing it here would cause a collision with OPEN
-clrchn:
+CLRCHN:
    jmp clrchn_real
@@ -1,23 +1,23 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 289
+// - [RG64] C64 Programmer's Reference Guide   - page 289
-;; - [CM64] Compute's Mapping the Commodore 64 - page 230/231
+// - [CM64] Compute's Mapping the Commodore 64 - page 230/231
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-open:
+OPEN:
-	;; Reset status
+	// Reset status
 	jsr kernalstatus_reset
-	;; Check if the logical file number is unique
+	// Check if the logical file number is unique
 	ldy LDTND
-*
+!:
-	beq +
+	beq !+
 	dey
 	lda LAT, y
 	cmp current_logical_filenum
@@ -25,23 +25,23 @@ open:
 	jmp kernalerror_FILE_ALREADY_OPEN
 open_not_yet_open:
 	cpy #$00
-	jmp -
+	jmp !-
-*
+!:
-	;; Check if we have space in tables
+	// Check if we have space in tables
 	ldy LDTND
 	cpy #$0A
 	bcc open_has_space
-*
+!:
-	;; Table is full
+	// Table is full
 	jmp kernalerror_TOO_MANY_OPEN_FILES
 open_has_space:
-	;; Update the tables
+	// Update the tables
-	;; LAT / FAT / SAT support implemented according to
+	// LAT / FAT / SAT support implemented according to
-	;; 'Compute's Mapping the Commodore 64', page 52
+	// 'Compute's Mapping the Commodore 64', page 52
 	lda current_logical_filenum
 	sta LAT, y
@@ -53,16 +53,16 @@ open_has_space:
 	iny
 	sty LDTND
-	;; Check for command to send
+	// Check for command to send
 	lda FNLEN
 	beq open_done_success
-	;; Check for IEC device
+	// Check for IEC device
 	lda current_device_number
 	jsr iec_check_devnum
 	bcc open_iec
-	;; FALLTROUGH
+	// FALLTROUGH
 open_done_success:
 	clc
@@ -70,21 +70,21 @@ open_done_success:
 open_iec:
-	;; We have a command to send to IEC device
+	// We have a command to send to IEC device
-	jsr listen
+	jsr LISTEN
-	bcc +
+	bcc !+
 	jmp kernalerror_DEVICE_NOT_FOUND
-*
+!:
 	lda current_secondary_address
 	jsr iec_cmd_open
-	bcc +
+	bcc !+
 	jmp kernalerror_DEVICE_NOT_FOUND
-*
+!:
-	;; We need our helpers to get to filenames under ROMs or IO area
+	// We need our helpers to get to filenames under ROMs or IO area
 	jsr install_ram_routines
-	;; Send command ('file name')
+	// Send command ('file name')
 	jsr lvs_send_file_name
 	jmp open_done_success
@@ -1,146 +1,146 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 286
+// - [RG64] C64 Programmer's Reference Guide   - page 286
-;; - [CM64] Compute's Mapping the Commodore 64 - page 231
+// - [CM64] Compute's Mapping the Commodore 64 - page 231
-;; - IEC reference at http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
+// - IEC reference at http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-	;; Expects that SETLFS and SETNAM are called before hand.
+	// Expects that SETLFS and SETNAM are called before hand.
-	;; $YYXX = load address.
+	// $YYXX = load address.
-	;; (ignored if SETLFS channel = 1, i.e., like ,8,1)
+	// (ignored if SETLFS channel = 1, i.e., like ,8,1)
-	;; If A=1 then VERIFY instead of LOAD.
+	// If A=1 then VERIFY instead of LOAD.
-	;; On exit, $YYXX is the highest address into which data
+	// On exit, $YYXX is the highest address into which data
-	;; will have been placed.
+	// will have been placed.
-	;; XXX honor MSGFLG bit 6
+	// XXX honor MSGFLG bit 6
-	;; XXX add VERIFY support
+	// XXX add VERIFY support
-load:
+LOAD:
-	;; Are we loading or verifying?
+	// Are we loading or verifying?
 	sta VERCK
-	;; Store start address of LOAD
+	// Store start address of LOAD
 	stx STAL+0
 	sty STAL+1
-	;; Reset status
+	// Reset status
 	jsr kernalstatus_reset
-	;; We need our helpers to get to filenames under ROMs or IO area
+	// We need our helpers to get to filenames under ROMs or IO area
 	jsr install_ram_routines
-	;; Allow platform-specific routine to takeover the flow
+	// Allow platform-specific routine to takeover the flow
-	`TARGET_HOOK_LOAD
+	TARGET_HOOK_LOAD()
-	;; Check whether we support the requested device
+	// Check whether we support the requested device
 	lda current_device_number
 	and #$FC
-	bne +
+	bne !+
-	jmp lvs_illegal_device_number ; device number below 4, not an IEC device
+	jmp lvs_illegal_device_number // device number below 4, not an IEC device
-*
+!:
-	;; Device numbers above 30 are also illegal (see https://www.pagetable.com/?p=1031),
+	// Device numbers above 30 are also illegal (see https://www.pagetable.com/?p=1031),
-	;; as the protocol combines device number with command code int one byte,
+	// as the protocol combines device number with command code int one byte,
-	;; above 30 it is no longer possible (UNLISTEN and UNTALK codes prevent using
+	// above 30 it is no longer possible (UNLISTEN and UNTALK codes prevent using
-	;; number 31), yet original ROMs show ILLEGAL DEVICE NUMBER error only
+	// number 31), yet original ROMs show ILLEGAL DEVICE NUMBER error only
-	;; for devices 0-3; in our implementation LISTEN / TALK will cause device
+	// for devices 0-3; in our implementation LISTEN / TALK will cause device
-	;; not present detected for numbers above 30
+	// not present detected for numbers above 30
-	;; Display SEARCHING FOR + filename
+	// Display SEARCHING FOR + filename
 	jsr lvs_display_searching_for
-	;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
+	// http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
-	;; p13, 16; also p16 tells us this routine doesn't mess with the file table
+	// p13, 16; also p16 tells us this routine doesn't mess with the file table
-	;; in the C64, only in the drive.
+	// in the C64, only in the drive.
-	;; Call device to LISTEN (p16)
+	// Call device to LISTEN (p16)
 	lda current_device_number
-	jsr listen
+	jsr LISTEN
-	bcc +
+	bcc !+
-	jmp lvs_device_not_found_error ; XXX deduplicate with other jumps in this routine
+	jmp lvs_device_not_found_error // XXX deduplicate with other jumps in this routine
-*
+!:
-	;; Open channel 0 (reserved for file reading)
+	// Open channel 0 (reserved for file reading)
 	lda #$00
 	jsr iec_cmd_open
-	bcc +
+	bcc !+
-	jmp lvs_device_not_found_error ; XXX deduplicate with other jumps in this routine
+	jmp lvs_device_not_found_error // XXX deduplicate with other jumps in this routine
-*
+!:
-	;; Send file name
+	// Send file name
 	jsr lvs_send_file_name
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*
+!:
-	;; Now command device to talk (p16)
+	// Now command device to talk (p16)
 	lda current_device_number
-	jsr talk
+	jsr TALK
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*
+!:
-	lda #$60 ; open channel / data (p3) , required according to p13
+	lda #$60 // open channel / data (p3) , required according to p13
 	sta IEC_TMP2
 	jsr iec_tx_command
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*
+!:
-	;; We are currently talker, so do the IEC turn around so that we
+	// We are currently talker, so do the IEC turn around so that we
-	;; are the listener (p16)
+	// are the listener (p16)
 	jsr iec_turnaround_to_listen
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*
+!:
-	;; Get load address and store it if secondary address is zero
+	// Get load address and store it if secondary address is zero
 	jsr iec_rx_byte
-	bcc +
+	bcc !+
-	jmp lvs_file_not_found_error ; XXX deduplicate with other jumps in this routine
+	jmp lvs_file_not_found_error // XXX deduplicate with other jumps in this routine
-*
+!:
 	ldx current_secondary_address
-	beq +
+	beq !+
 	sta STAL+0
-*
+!:
 	jsr iec_rx_byte
-	bcc +
+	bcc !+
-	jmp lvs_file_not_found_error ; XXX deduplicate with other jumps in this routine
+	jmp lvs_file_not_found_error // XXX deduplicate with other jumps in this routine
-*
+!:
 	ldx current_secondary_address
-	beq +
+	beq !+
 	sta STAL+1
-*
+!:
-	;; Display start address
+	// Display start address
 	jsr lvs_display_loading_verifying
 load_loop:
-	;; We are now ready to receive bytes
+	// We are now ready to receive bytes
 	jsr iec_rx_byte
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*
+!:
-	;; Handle the byte (store in memory / verify)
+	// Handle the byte (store in memory / verify)
 	jsr lvs_handle_byte_load_verify
-	bcc +
+	bcc !+
-	jmp lvs_load_verify_error ; XXX deduplicate with other jumps in this routine 
+	jmp lvs_load_verify_error // XXX deduplicate with other jumps in this routine 
-*	
+!:	
-	;; Advance pointer to data
+	// Advance pointer to data
 	jsr lvs_advance_pointer
-	bcc +
+	bcc !+
 	jmp lvs_wrap_around_error
-*
+!:
-	;; Check for EOI - if so, this was the last byte
+	// Check for EOI - if so, this was the last byte
 	lda IOSTATUS
 	and #K_STS_EOI
 	beq load_loop
-	;; Display end address
+	// Display end address
 	jsr lvs_display_done
-	;; Close file on drive
+	// Close file on drive
 	lda current_device_number
 	jsr close_load
-	;; Return last address
+	// Return last address
 	jmp lvs_return_last_address
@@ -1,13 +1,13 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 293/294
+// - [RG64] C64 Programmer's Reference Guide   - page 293/294
-;; - [CM64] Compute's Mapping the Commodore 64 - page 231/232
+// - [CM64] Compute's Mapping the Commodore 64 - page 231/232
-;; - IEC reference at http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
+// - IEC reference at http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-save:
+SAVE:
 	rts
@@ -1,24 +1,24 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 301
+// - [RG64] C64 Programmer's Reference Guide   - page 301
-;; - [CM64] Compute's Mapping the Commodore 64 - page 232
+// - [CM64] Compute's Mapping the Commodore 64 - page 232
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): .Y
+// CPU registers that has to be preserved (see [RG64]): .Y
-;;
+//
-stop:
+STOP:
-	;; Bit 7 of STKEY contains the state of the STOP key
+	// Bit 7 of STKEY contains the state of the STOP key
-	;; (Compute's Mapping the 64, p27)
+	// (Compute's Mapping the 64, p27)
-	;; BASIC checks carry flag to indicate STOP or not
+	// BASIC checks carry flag to indicate STOP or not
 	lda STKEY
 	bpl stop_pressed
-	;; By trial and error, we know that Z + C = BREAK
+	// By trial and error, we know that Z + C = BREAK
-	;; and that neither should be set otherwise
+	// and that neither should be set otherwise
-	lda #$ff
+	lda #$FF
 	clc
 	rts
@@ -1,70 +1,64 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 293 (RESTOR), 304 (VECTOR)
+// - [RG64] C64 Programmer's Reference Guide   - page 293 (RESTOR), 304 (VECTOR)
-;; - [CM64] Compute's Mapping the Commodore 64 - page 237
+// - [CM64] Compute's Mapping the Commodore 64 - page 237
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-restor:
+RESTOR:
-	clc ;; clear carry - for writing to system table
+	clc // clear carry - for writing to system table
 	ldx #<vector_defaults
 	ldy #>vector_defaults
-	;; FALLTHROUGH
+	// FALLTHROUGH
-vector:
+VECTOR:
-.scope
+	// Temporary storage location - checked on real C64 that this is the
 	// address originally used; after calling VECTOR and checking zero page
 	// area afterwards, the address could be found there
 	.label _caller_arr_ptr = MEMUS
-	;; Temporary storage location - checked on real C64 that this is the
+	// According to 'Compute's Mapping the Commodore 64' page 237,
-	;; address originally used; after calling VECTOR and checking zero page
+	// the CBM implementation does not disable IRQs - yet, the
-	;; area afterwards, the address could be found there
+	// 'C64 Programmers Reference Guide' does not contain such
-	.alias _caller_arr_ptr MEMUS
+	// warning and does not mention any preparations needed, so...
-
+	// better safe than sorry, disable the IRQ for the duration
-	;; According to 'Compute's Mapping the Commodore 64' page 237,
+	// of vector manipulation
 	;; the CBM implementation does not disable IRQs - yet, the
 	;; 'C64 Programmers Reference Guide' does not contain such
 	;; warning and does not mention any preparations needed, so...
 	;; better safe than sorry, disable the IRQ for the duration
 	;; of vector manipulation
 	php
 	cli
-	;; Prepare the user data pointer - strange order to reduce risk
+	// Prepare the user data pointer - strange order to reduce risk
-	;; of potential similarity to the original routine
+	// of potential similarity to the original routine
 	sty _caller_arr_ptr + 1
 	stx _caller_arr_ptr + 0
-	;; Select routine variant - store or restore vectors
+	// Select routine variant - store or restore vectors
 	ldy #$1F
 	bcc vector_restore
-	;; FALLTHROUGH
+	// FALLTHROUGH
 vector_store:
 *
 	lda CINV, y
 	sta (_caller_arr_ptr), y
 	dey
-	bpl -
+	bpl vector_store
-	;; Restore status register (IRQ) before return
+	// Restore status register (IRQ) before return
 	plp
 	rts
 vector_restore:
 *
 	lda (_caller_arr_ptr), y
 	sta CINV, y
 	dey
-	bpl -
+	bpl vector_restore
-	;; Restore status register (IRQ) before return
+	// Restore status register (IRQ) before return
 	plp
 	rts
 .scend
@@ -1,34 +1,34 @@
-;;
+//
-;; Official Kernal routine, described in:
+// Official Kernal routine, described in:
-;;
+//
-;; - [RG64] C64 Programmer's Reference Guide   - page 285
+// - [RG64] C64 Programmer's Reference Guide   - page 285
-;; - [CM64] Compute's Mapping the Commodore 64 - page 238
+// - [CM64] Compute's Mapping the Commodore 64 - page 238
-;;
+//
-;; CPU registers that has to be preserved (see [RG64]): none
+// CPU registers that has to be preserved (see [RG64]): none
-;;
+//
-ioinit:
+IOINIT:
-	; Set $00/$01 port mode and value
+	// Set $00/$01 port mode and value
-	; We want BASIC and KERNAL ROMs mapped, and datasette motor off
+	// We want BASIC and KERNAL ROMs mapped, and datasette motor off
-	; (https://www.c64-wiki.com/wiki/Zeropage)
+	// (https://www.c64-wiki.com/wiki/Zeropage)
-	;; XXX - Work around VICE bug: Writing $00 before $01 results in rubbish in $01
+	// XXX - Work around VICE bug: Writing $00 before $01 results in rubbish in $01
-	;; after. https://sourceforge.net/p/vice-emu/bugs/1057/
+	// after. https://sourceforge.net/p/vice-emu/bugs/1057/
 	lda #$27
 	ldx #$2F
 	sta CPU_R6510
 	stx CPU_D6510
-	;; Silence the SID chips under common addresses
+	// Silence the SID chips under common addresses
 	ldy #$00
-*
+!:
-	;; SIDs under $D4xx
+	// SIDs under $D4xx
 	lda SID_SIGVOL, Y
 	and #$F0
 	sta SID_SIGVOL, Y
-	;; SIDs under $D5xx
+	// SIDs under $D5xx
 	lda SID_SIGVOL + $100, Y
 	and #$F0
 	sta SID_SIGVOL + $100, Y
@@ -36,24 +36,24 @@ ioinit:
 	clc
 	adc #$20
 	tay
-	bne -
+	bne !-
-	;; XXX: calibrate TOD for both CIA's, see here: https://codebase64.org/doku.php?id=base:efficient_tod_initialisation
+	// XXX: calibrate TOD for both CIA's, see here: https://codebase64.org/doku.php?id=base:efficient_tod_initialisation
-	;; Enable CIA1 IRQ and ~50Hz timer (https://csdb.dk/forums/?roomid=11&topicid=69037)
+	// Enable CIA1 IRQ and ~50Hz timer (https://csdb.dk/forums/?roomid=11&topicid=69037)
 	lda #$7F
-	sta CIA1_ICR ; disable all
+	sta CIA1_ICR // disable all
-	;; Set timer interval to ~1/60th of a second
+	// Set timer interval to ~1/60th of a second
-	;; (This value was calculated by running a custom IRQ handler on a C64
+	// (This value was calculated by running a custom IRQ handler on a C64
-	;; with original KERNAL, and writing the values of $DC04/5 to the screen
+	// with original KERNAL, and writing the values of $DC04/5 to the screen
-	;; in the IRQ handler to see roughly what value the timers must be set to)
+	// in the IRQ handler to see roughly what value the timers must be set to)
-	;; ldy #<16380
+	// ldy #<16380
-	;; ldx #>16380
+	// ldx #>16380
-	;; PAL C64 (https://codebase64.org/doku.php?id=base:cpu_clocking),
+	// PAL C64 (https://codebase64.org/doku.php?id=base:cpu_clocking),
-	;; is clocked at 0.985248 MHz, so that 1/60s is 16421 CPU cycles
+	// is clocked at 0.985248 MHz, so that 1/60s is 16421 CPU cycles
 	ldy #<16421
 	ldx #>16421
@@ -61,19 +61,19 @@ ioinit:
 	sty CIA1_TIMALO
 	stx CIA1_TIMAHI
-	;; Enable timer interrupt
+	// Enable timer interrupt
 	lda #$81
 	sta CIA1_ICR
-	;; Enable timer A to run continuously (http://codebase64.org/doku.php?id=base:timerinterrupts)
+	// Enable timer A to run continuously (http://codebase64.org/doku.php?id=base:timerinterrupts)
 	lda #$11
 	sta CIA1_CRA
 	lda CIA1_ICR
-	;; Set DDR on CIA2 for IEC bus, VIC-II banking
+	// Set DDR on CIA2 for IEC bus, VIC-II banking
 	lda #$3B
 	sta CIA2_DDRA
-	;; Set IEC bus to its initial idle state
+	// Set IEC bus to its initial idle state
 	jmp iec_set_idle
@@ -1,6 +1,6 @@
-;; Our implementation is longer than the original one,
+// Our implementation is longer than the original one,
-;; placing it here would cause a collision with OPEN
+// placing it here would cause a collision with OPEN
-cint:
+CINT:
    jmp cint_real
@@ -1,31 +1,63 @@
-;;
+//
-;; This byte identifies Kernal revision. Sources:
+// This byte (hex $FF80, dec 65408) identifies Kernal revision on several machines. Although not all
-;; - [CM64]  Compute's Mapping the Commodore 64 (page 242/243)
+// of the, used it for versioning purpose, here is the list of all the values I could find. Sources:
-;; - [MM]    Marko Mäkelä article, http://www.zimmers.net/anonftp/pub/cbm/firmware/computers/c64/revisions.txt
+// - [CM64]  Compute's Mapping the Commodore 64 (page 242/243)
-;; - [VICE]  Checked with ROMs included in VICE emulator
+// - [MM]    Marko Mäkelä article, http://www.zimmers.net/anonftp/pub/cbm/firmware/computers/c64/revisions.txt
-;;
+// - [VICE]  Checked with ROMs included in VICE emulator
-;; IDEA: put here a value, that is different from any version currently known, as
+// - [XEMU]  Checked with ROMs retrieved by XEMU emulator
-;; a warning that this is not a Commodore Kernal. Currently known numbers for C64 are:
+//
-;;
+// IDEA: put here a value, that is different from any version currently known, as
-;; - $00 - [CM64] then current number    [MM] 901227-02             [VICE] C64 Revision 2
+// a warning that this is not a Commodore Kernal or anything already known.
-;; - $03 - [CM64] (not mentionned)       [MM] 901227-02, 901227-03  [VICE] C64 Revision 3
+//
-;; - $43 - [CM64] (not mentionned)       [MM] 251104-04             [VICE] SX-64
+// C64 - values from the official ROMs:
-;; - $64 - [CM64] PET64 ROM              [MM] (not mentionned)      [VICE] PET64
+// - $00 - [CM64] then current number    [MM] 901227-02             [VICE] C64 Revision 2
-;; - $AA - [CM64] first version of ROM   [MM] 901227-01             [VICE] C64 Revision 1
+// - $03 - [CM64] (not mentionned)       [MM] 901227-02, 901227-03  [VICE] C64 Revision 3
-;;
+// - $43 - [CM64] (not mentionned)       [MM] 251104-04             [VICE] SX-64
-;; Values from unofficial ROMs:
+// - $64 - [CM64] PET64 ROM              [MM] (not mentionned)      [VICE] PET64
-;; - $03 - SuperCPU ROM 1.40, 2.04, also unofficial 0.7 ROM from [VICE]
+// - $AA - [CM64] first version of ROM   [MM] 901227-01             [VICE] C64 Revision 1
-;; 
+//
-;; Values from other Commodore machines:
+// C64 - values from unofficial 3rd party ROMs:
-;; C128:
+// - $00 - Turbo Trans, Turbo Access, Turbo Process
-;; - $01 - see https://www.pagetable.com/?p=1058
+// - $03 - SuperCPU ROM 1.40, 2.04, also unofficial 0.7 ROM from [VICE],
-;; - $02 - unreleased updated ROM, see https://www.pagetable.com/?p=1058
+//         DolphinDOS 2.0, JiffyDOS 6.01, EXOS V3/4,
-;;
+//         Datel Mercury V3 US, Datel DOS-ROM V1.2, Datel Turbo ROM II V3.2+,
-;; XXX check more unofficial C64 ROMs (JiffyDOS, DolphinDOS, etc.) and other machines
+//         Turbo Process US,
-;;     VIC-20, PET, CBM II, 264 series, C65 prototypes, other sources for C128 ROMs
+//         burst CIA 1/2 Kernal by Albert, SD2IEC Kernal 1.0/2.0/2.1/2.2 by Claus
-;;
+// - $4A - S-JiffyDOS
-
+// - $53 - Professional DOS V1, SpeedDOS Plus 2.7
 // - $C3 - Cockroach Turbo ROM V1
 //
 // PET:
 // - $40 - [VICE] PET 2001-8N
 // - $A7 - [VICE] PET 30XX
 // - $AA - [VICE] PET 40XX, PET 80XX, SuperPET
 //
 // CBM II:
 // - $E0 - [VICE] 5x0, 6x0, 7x0 models
 //
 // VIC-20:
 // - $16 - [VICE] all models, also VIC-20 JiffyDOS PAL/NTSC
 //
 // 264 family:
 // - $01 - [VICE] 364
 // - $05 - [VICE] C16, C116, Plus/4
 // - $06 - (unofficial) JiffyDOS NTSC
 // - $81 - [VICE] 232
 // - $86 - (unofficial) JiffyDOS PAL
 //
 // C128:
 // - $01 - see https://www.pagetable.com/?p=1058
 // - $02 - unreleased updated ROM, see https://www.pagetable.com/?p=1058
 //
 // Commodore prototypes:
 // - $04 - [XEMU] 64 mode ROM of the C65 prototype, ROM 910111
 // - $FF - [XEMU] C65 native mode, ROM 910111
 // - $FF - [XEMU] Commodore LCD
 //
 // Non-Commodore machines:
 // - $FF - Commander X16 (emulator r28)
 //
 kernal_revision:
-    .byte $FF
+    .byte $FF // XXX possibly change this value (current candidate: $F0), $FF conflicts with other machines
@@ -1,4 +1,4 @@
-; $FFFA - CPU NMI Hanlder
+// $FFFA - CPU NMI Hanlder
-; Uncontrovertial as this is also a CPU requirement.
+// Uncontrovertial as this is also a CPU requirement.
 	.word nmi_handler
@@ -1,4 +1,4 @@
-; $FFFC - CPU Reset Vector
+// $FFFC - CPU Reset Vector
-; Uncontrovertial, as it is a CPU requirement, and nothing else.
+// Uncontrovertial, as it is a CPU requirement, and nothing else.
 	.word reset_entry
@@ -1,5 +1,5 @@
-; $FFFE - CPU IRQ Vector.
+// $FFFE - CPU IRQ Vector.
-; This is non-controvertial, as it is a 6502 CPU requirement, and we just have to point
+// This is non-controvertial, as it is a 6502 CPU requirement, and we just have to point
-; it to whatever IRQ routine we make.
+// it to whatever IRQ routine we make.
 	.word irq_handler
@@ -1,18 +1,18 @@
-;; Just a helper routines
+// Just a helper routines
-;; Find the LAT / SAT / FAT entry index where LAT corresponds to A, returns index in Y
+// Find the LAT / SAT / FAT entry index where LAT corresponds to A, returns index in Y
-;; Carry flag set means not found
+// Carry flag set means not found
 find_fls:
 	ldy LDTND
-	beq find_fls_not_found ; table empty
+	beq find_fls_not_found // table empty
-*
+!:
 	dey
-	bmi find_fls_not_found ; no more entries
+	bmi find_fls_not_found // no more entries
 	cmp LAT, y
-	bne - ; does not match, try the next one
+	bne !- // does not match, try the next one
 	clc
 	rts
@@ -1,5 +1,5 @@
-	;; Home the cursor
+// Home the cursor
-	;; (Compute's Mapping the 64 p216)
+// (Compute's Mapping the 64 p216)
 home_cursor:
@@ -1,22 +1,22 @@
-;;
+//
-;; Checks whether device number (in .A) is a correct IEC device number
+// Checks whether device number (in .A) is a correct IEC device number
-;;
+//
-;; Preserves .A, .X and .Y
+// Preserves .A, .X and .Y
-;;
+//
 iec_check_devnum:
-	;; 0, 1, 2, or 3 are illegal - reserved for non-IEC devices on Commodore
+	// 0, 1, 2, or 3 are illegal - reserved for non-IEC devices on Commodore
 	cmp #$04
-	bcs +
+	bcs !+
-	;; FALLTROUGH
+	// FALLTROUGH
 iec_check_devnum_failed:
-	sec ; indicate non-IEC device
+	sec // indicate non-IEC device
 	rts
-*
+!:
-	;; 31 and above are illegal too, due to IEC command encoding scheme,
+	// 31 and above are illegal too, due to IEC command encoding scheme,
-	;; see https://www.pagetable.com/?p=1031
+	// see https://www.pagetable.com/?p=1031
 	cmp #$1F
 	bcs iec_check_devnum_failed
-	;; Carry is clear here - indicates IEC device
+	// Carry is clear here - indicates IEC device
 	rts
@@ -1,16 +1,16 @@
-;;
+//
-;; Kernal internal IEC routine
+// Kernal internal IEC routine
-;;
+//
-;; - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc
+// - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc
-;;
+//
 iec_cmd_close:
 	jsr iec_check_channel_openclose
-	bcc +
+	bcc !+
 	jmp kernalerror_FILE_NOT_INPUT
-*
+!:
 	ora #$E0
 	jmp common_open_close_unlsn_second
@@ -1,42 +1,42 @@
-;;
+//
-;; Kernal internal IEC routine
+// Kernal internal IEC routine
-;;
+//
-;; - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc
+// - https://www.pagetable.com/?p=1031, https://github.com/mist64/cbmbus_doc
-;;
+//
-iec_cmd_open: ; similar to TKSA, but without turnaround
+iec_cmd_open: // similar to TKSA, but without turnaround
 	jsr iec_check_channel_openclose
-	bcc +
+	bcc !+
 	jmp kernalerror_FILE_NOT_INPUT
-*
+!:
 	ora #$F0
-	;; FALLTROUGH
+	// FALLTROUGH
-common_open_close_unlsn_second: ; common part of several commands
+common_open_close_unlsn_second: // common part of several commands
 	sta IEC_TMP2
 	jsr iec_tx_command
-	bcs + ; branch if error
+	bcs !+ // branch if error
 	jmp iec_tx_command_finalize
-*
+!:
 	rts
 iec_check_channel_openclose:
-	;; Due to OPEN/CLOSE/TKSA/SECOND command encoding (see https://www.pagetable.com/?p=1031),
+	// Due to OPEN/CLOSE/TKSA/SECOND command encoding (see https://www.pagetable.com/?p=1031),
-	;; allowed channels are 0-15; report error if out of range
+	// allowed channels are 0-15; report error if out of range
 	cmp #$10
-	bcc + 
+	bcc !+ 
-	;; Workaround to allow reading executable files and disk directory
+	// Workaround to allow reading executable files and disk directory
-	;; using OPEN routine - see https://www.pagetable.com/?p=273 for
+	// using OPEN routine - see https://www.pagetable.com/?p=273 for
-	;; example usage
+	// example usage
 	cmp #$60
-	beq +
+	beq !+
-	sec ; mark unsuitable channel number
+	sec // mark unsuitable channel number
 	rts
-*
+!:
-	clc ; mark suitable channel number
+	clc // mark suitable channel number
 	rts
		`@@ -0,0 +1 @@`
							`Put KickAss.jar and KickAss.cfg into this directory.`
`@@ -1,3 +1,4 @@`
	`;; Compute's Mapping the C64 p88`	`// Compute's Mapping the C64 p88`

	`.word basic_cold_start`	`.word basic_cold_start`
`@@ -1,2 +1,3 @@`
	`;; Compute's Mapping the C64 p88`	`// Compute's Mapping the C64 p88`

	`.word basic_warm_start`	`.word basic_warm_start`