Kernal size optimizations

STATUS.md

@@ -50,29 +50,41 @@ The following ROM features are currently missing:
 
 ## Keyboard
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
 | C64                | DONE     |                                                    |
 | C128               | DONE     |                                                    |
 | Mega65             | NOT DONE | code should be complete, but is not tested yet     |
 
+<br />
+
 ## Screen
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
 | VIC-II             | DONE     |                                                    |
 | 80 columns, VDC    | NOT DONE |                                                    |
 | 80 columns, Mega65 | NOT DONE |                                                    |
 
+<br />
+
 ## Tape port (LOAD only!)
 
 * Tapuino
 * Datasette
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
-| normal             | DONE     |                                                    |
+| normal             | DONE     | up to 202 blocks, like original ROM                |
-| turbo (250 blocks) | DONE     |                                                    |
+| turbo              | DONE     | up to 250 blocks, like the best implementations    |
+
+<br />
 
 ## IEC bus
 
@@ -81,6 +93,8 @@ The following ROM features are currently missing:
 * most disk drives and printers
 * some hard drives
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
 | standard           | DONE     |                                                    |
@@ -89,27 +103,36 @@ The following ROM features are currently missing:
 | CIA burst mod      | NOT DONE |                                                    |
 | Mega65 burst       | NOT DONE |                                                    |
 
+<br />
+
 ## IEEE-488 bus
 
 * petSD+
 * PET era disk drives and printers
 * various scientific equipment
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
 | CBM cartridge      | NOT DONE |                                                    |
 
+<br />
+
 ## RS-232
 
 * modems (telephone, WiFi)
 * parallel port printers
 
+<br />
+
 | Driver             | Status   |  Remarks                                           |
 | :----------------: | :------: | :------------------------------------------------: |
 | UP2400             | NOT DONE |                                                    |
 | UP9600             | NOT DONE | work started, not functional yet                   |
 | ACIA 6551          | NOT DONE |                                                    |
 
+<br />
 
 # API status
 
@@ -202,19 +225,19 @@ Not all of them - only these we want to have implemented.
 | Address   | Name         | Status   |  Remarks                                           |
 | :-------: | :----------- | :------: | :------------------------------------------------: |
 | `$A004`   | revision str | DONE     |                                                    |
-| `$A408`   | REASON       | NOT DONE |                                                    |
+| `$A408`   | `REASON`     | NOT DONE |                                                    |
 | `$A453`   | (unknown)    | NOT DONE |                                                    |
-| `$A533`   | LINKPRG      | DONE     |                                                    |
+| `$A533`   | `LINKPRG`    | DONE     |                                                    |
 | `$A644`   | new          | NOT DONE |                                                    |
 | `$A659`   | set txt ptr  | NOT DONE |                                                    |
-| `$A68E`   | RUNC         | DONE     |                                                    |
+| `$A68E`   | `RUNC`       | DONE     |                                                    |
-| `$A7AE`   | NEWSTT       | PARTIAL  | redirected to RUN command                          |
+| `$A7AE`   | `NEWSTT`     | PARTIAL  | redirected to RUN command                          |
-| `$AB1E`   | STROUT       | DONE     |                                                    |
+| `$AB1E`   | `STROUT`     | DONE     |                                                    |
-| `$AD9E`   | FRMEVL       | NOT DONE |                                                    |
+| `$AD9E`   | `FRMEVL`     | NOT DONE |                                                    |
-| `$BDCD`   | LINPRT       | DONE     | temporary implementation                           |
+| `$BDCD`   | `LINPRT`     | DONE     | temporary implementation                           |
-| `$E3BF`   | INIT         | NOT DONE |                                                    |
+| `$E3BF`   | `INIT`       | NOT DONE |                                                    |
-| `$E422`   | INITMSG      | DONE     |                                                    |
+| `$E422`   | `INITMSG`    | DONE     |                                                    |
-| `$E453`   | RVECT        | NOT DONE |                                                    |
+| `$E453`   | `RVECT`      | NOT DONE |                                                    |
 
 <br />
 

c64/kernal/banking/4000.mega65_vectable_kernal_1.s

@@ -11,16 +11,20 @@
 
 	// Label definitions
 
-	.label VK1__RAMTAS                 = $4000 + 2 * 0
+	.label VK1__IOINIT                 = $4000 + 2 * 0
-	.label VK1__load_tape_normal       = $4000 + 2 * 1
+	.label VK1__RAMTAS                 = $4000 + 2 * 1
-	.label VK1__load_tape_turbo        = $4000 + 2 * 2
+	.label VK1__setup_vicii            = $4000 + 2 * 2
-	.label VK1__load_tape_auto         = $4000 + 2 * 3
+	.label VK1__load_tape_normal       = $4000 + 2 * 3
+	.label VK1__load_tape_turbo        = $4000 + 2 * 4
+	.label VK1__load_tape_auto         = $4000 + 2 * 5
 
 #else
 
 	// Vector table (OpenROMs private!)
 
+	.word IOINIT
 	.word RAMTAS
+	.word setup_vicii
 
 #if CONFIG_TAPE_NORMAL && !CONFIG_TAPE_AUTODETECT
 	.word load_tape_normal

c64/kernal/banking/mega65_imports.s

@@ -9,11 +9,20 @@
 
 
 .label STOP                            = KERNAL_0.STOP
+.label clrchn_reset                    = KERNAL_0.clrchn_reset
 .label udtim_keyboard                  = KERNAL_0.udtim_keyboard
 
+.label setup_irq_timer                 = KERNAL_0.setup_irq_timer
 .label wait_x_bars                     = KERNAL_0.wait_x_bars
 
 
+#if CONFIG_IEC
+
+.label iec_set_idle                    = KERNAL_0.iec_set_idle
+
+#endif
+
+
 #if CONFIG_TAPE_NORMAL || CONFIG_TAPE_TURBO
 
 .label screen_on                       = KERNAL_0.screen_on

c64/kernal/errors.s

@@ -6,90 +6,78 @@
 // Kernal error codes are described in 'Commodore 64 Programmers Reference Guide', page 306
 
 kernalerror_ROUTINE_TERMINATED: // by a STOP key
+
 	lda #K_ERR_ROUTINE_TERMINATED
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_TOO_MANY_OPEN_FILES:
+
 	lda #K_ERR_TOO_MANY_OPEN_FILES
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_ALREADY_OPEN:
+
 	lda #K_ERR_FILE_ALREADY_OPEN
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_NOT_OPEN:
+
 	lda #K_ERR_FILE_NOT_OPEN
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_NOT_FOUND:
+
 	lda #K_ERR_FILE_NOT_FOUND
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_DEVICE_NOT_FOUND:
+
 	lda #K_ERR_DEVICE_NOT_FOUND
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_NOT_INPUT:
+
 	lda #K_ERR_FILE_NOT_INPUT
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_NOT_OUTPUT:
+
 	lda #K_ERR_FILE_NOT_OUTPUT
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_FILE_NAME_MISSING:
+
 	lda #K_ERR_FILE_NAME_MISSING
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_ILLEGAL_DEVICE_NUMBER:
+
 	lda #K_ERR_ILLEGAL_DEVICE_NUMBER
-	sec
+	skip_2_bytes_trash_nvz
-	rts
+
+	// FALLTROUGH
 
 kernalerror_TOP_MEM_RS232:
+
 	lda #K_ERR_TOP_MEM_RS232
+
 	sec
 	rts
-
-
-// Kernal status codes are described in 'Commodore 64 Programmers Reference Guide', page 292
-
-kernalstatus_reset:
-	lda #$00
-	sta IOSTATUS
-	rts
-
-// The following two statuses are currently not implemented - and most likely not really needed
-
-// kernalstatus_TIMEOUT_WRITE:
-//	lda IOSTATUS
-//	ora #K_STS_TIMEOUT_WRITE
-//	sta IOSTATUS
-//	rts
-
-// kernalstatus_TIMEOUT_READ:
-//	lda IOSTATUS
-//	ora #K_STS_TIMEOUT_READ
-//	sta IOSTATUS
-//	rts
-
-kernalstatus_EOI:
-	lda IOSTATUS
-	ora #K_STS_EOI
-	sta IOSTATUS
-	rts
-
-kernalstatus_DEVICE_NOT_FOUND:
-	lda IOSTATUS
-	ora #K_STS_DEVICE_NOT_FOUND
-	sta IOSTATUS
-	rts

c64/kernal/init/e5a0.setup_vicii.s

@@ -1,5 +1,6 @@
 // #LAYOUT# STD *        #TAKE
-// #LAYOUT# *   KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_1 #TAKE-FLOAT
 // #LAYOUT# *   *        #IGNORE
 
 //
@@ -11,6 +12,14 @@
 
 setup_vicii:
 
+#if (ROM_LAYOUT_M65 && SEGMENT_KERNAL_0)
+
+	jsr     map_KERNAL_1
+	jsr_ind VK1__setup_vicii
+	jmp     map_NORMAL
+
+#else
+
 	// Clear everything - turn off sprites (observed hanging around after
  	// running programs and resetting), etc.
 
@@ -67,3 +76,5 @@ setup_vicii:
 	// Setup default I/O devices
 
 	jmp clrchn_reset
+
+#endif // ROM layout

c64/kernal/init/fda3.ioinit.s

@@ -1,5 +1,6 @@
 // #LAYOUT# STD *        #TAKE
-// #LAYOUT# *   KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_0 #TAKE
+// #LAYOUT# M65 KERNAL_1 #TAKE-FLOAT
 // #LAYOUT# *   *        #IGNORE
 
 //
@@ -14,6 +15,14 @@
 
 IOINIT:
 
+#if (ROM_LAYOUT_M65 && SEGMENT_KERNAL_0)
+
+	jsr     map_KERNAL_1
+	jsr_ind VK1__IOINIT
+	jmp     map_NORMAL
+
+#else
+
 	//
 	// First initialize the CPU port, to make sure we have correct memory map
 	//
@@ -146,3 +155,6 @@ IOINIT:
 	rts
 
 #endif
+
+
+#endif // ROM layout

c64/kernal/status.s

@@ -0,0 +1,42 @@
+// #LAYOUT# STD *        #TAKE
+// #LAYOUT# *   KERNAL_0 #TAKE
+// #LAYOUT# *   *        #IGNORE
+
+
+// Kernal status codes are described in 'Commodore 64 Programmers Reference Guide', page 292
+
+kernalstatus_reset:
+	lda #$00
+	beq kernalstatus_end               // branch always
+
+// The following two statuses are currently not implemented - and most likely not really needed
+
+// kernalstatus_TIMEOUT_WRITE:
+//
+//	lda IOSTATUS
+//	ora #K_STS_TIMEOUT_WRITE
+//	bne kernalstatus_end               // branch always
+
+// kernalstatus_TIMEOUT_READ:
+//
+//	lda IOSTATUS
+//	ora #K_STS_TIMEOUT_READ
+//	bne kernalstatus_end               // branch always
+
+kernalstatus_EOI:
+
+	lda IOSTATUS
+	ora #K_STS_EOI
+	bne kernalstatus_end               // branch always
+
+kernalstatus_DEVICE_NOT_FOUND:
+
+	lda IOSTATUS
+	ora #K_STS_DEVICE_NOT_FOUND
+
+	// FALLTROUGH
+
+kernalstatus_end:
+
+	sta IOSTATUS
+	rts