diff --git a/bin/basic_generic.rom b/bin/basic_generic.rom
index 966d794a..826cc63b 100644
Binary files a/bin/basic_generic.rom and b/bin/basic_generic.rom differ
diff --git a/bin/basic_mega65.rom b/bin/basic_mega65.rom
index 20dc20c0..071c0b5b 100644
Binary files a/bin/basic_mega65.rom and b/bin/basic_mega65.rom differ
diff --git a/bin/basic_ultimate64.rom b/bin/basic_ultimate64.rom
index 482ff397..da45a31a 100644
Binary files a/bin/basic_ultimate64.rom and b/bin/basic_ultimate64.rom differ
diff --git a/bin/kernal_generic.rom b/bin/kernal_generic.rom
index 32bd602e..1765f7d2 100644
Binary files a/bin/kernal_generic.rom and b/bin/kernal_generic.rom differ
diff --git a/bin/kernal_mega65.rom b/bin/kernal_mega65.rom
index f6b0fd85..5660cad6 100644
Binary files a/bin/kernal_mega65.rom and b/bin/kernal_mega65.rom differ
diff --git a/bin/kernal_ultimate64.rom b/bin/kernal_ultimate64.rom
index a52e636e..f853f836 100644
Binary files a/bin/kernal_ultimate64.rom and b/bin/kernal_ultimate64.rom differ
diff --git a/c64/aliases/,aliases_hardware.s b/c64/aliases/,aliases_hardware.s
index 343fb5db..73abfd8c 100644
--- a/c64/aliases/,aliases_hardware.s
+++ b/c64/aliases/,aliases_hardware.s
@@ -10,7 +10,7 @@
 
 	// VIC-II registers
 
-	.label VIC_BASE     = $D000  // base address of the chip
+	.label __VIC_BASE   = $D000  // base address of the chip
 
 	.label VIC_SP0X     = $D000
 	.label VIC_SP0Y     = $D001
@@ -64,7 +64,7 @@
 	
 	// SID registers
 
-	.label SID_BASE     = $D400  // base address of the chip
+	.label __SID_BASE   = $D400  // base address of the chip
 
 	.label SID_FRELO1   = $D400
 	.label SID_FREHI1   = $D401
@@ -101,7 +101,7 @@
 
 	// CIA #1 registers
 
-	.label CIA1_BASE    = $DC00  // base address of the chip
+	.label __CIA1_BASE  = $DC00  // base address of the chip
 
 	.label CIA1_PRA     = $DC00
 	.label CIA1_PRB     = $DC01
@@ -125,7 +125,7 @@
 
 	// CIA #2 registers
 
-	.label CIA2_BASE    = $DD00  // base address of the chip
+	.label __CIA2_BASE  = $DD00  // base address of the chip
 
 	.label CIA2_PRA     = $DD00  // VIC bank switching and IEC port
 	.label CIA2_PRB     = $DD01
diff --git a/c64/aliases/,aliases_ram_lowmem.s b/c64/aliases/,aliases_ram_lowmem.s
index 8a18c4af..0c63eaa0 100644
--- a/c64/aliases/,aliases_ram_lowmem.s
+++ b/c64/aliases/,aliases_ram_lowmem.s
@@ -166,13 +166,13 @@
 	.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 KOUNT     = $28B  //            key repeat counter
 	.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 KEYLOG    = $28F  // $28F-$290  -- NOT IMPLEMENTED -- keyboard decoding pointer
 	.label MODE      = $291  //            flag, is case switch allowed
-	.label AUTODN    = $292  //            -- NOT IMPLEMENTED --
+	.label AUTODN    = $292  //            -- NOT IMPLEMENTED -- screen scroll disable
 	.label M51CRT    = $293  //            -- NOT IMPLEMENTED -- mock 6551
 	.label M51CDR    = $294  //            -- NOT IMPLEMENTED -- mock 6551
 	.label M51AJB    = $295  // $295-$296  -- NOT IMPLEMENTED -- mock 6551
diff --git a/c64/basic/,aliases.s b/c64/basic/,aliases.s
index e2a02afb..ef91afa0 100644
--- a/c64/basic/,aliases.s
+++ b/c64/basic/,aliases.s
@@ -60,7 +60,6 @@
 	// 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
@@ -80,7 +79,6 @@
 	.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
@@ -91,28 +89,6 @@
 	.label current_screen_line_colour_ptr = $F3
 	.label keyboard_decoding_table_ptr = $F5
 
-	.label basic_input_buffer = BUF
-
-	// "Compute's Mapping the 64" book
-	.label keyboard_buffer = $0277
-	.label text_colour = $0286 // p55
-	.label colour_under_cursor = $0287 // p56
-	.label key_buffer_size = $0289 // p57
-
-	// 0 = cursor keys, insert, delete and space repeat, but nothing else
-	// 128 = all keys repeat
-	// 64 = no keys repeat
-	.label key_repeat_flags = $028A // p58
-	// https://www.c64-wiki.com/wiki/Page_2
-	.label key_repeat_counter = $028B
-	.label key_first_repeat_delay = $028C
-	// 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
-
 #if CONFIG_MEMORY_MODEL_60K
 
 	// BASIC uses some extra bytes for memory access under ROMs located at $2A7 onwards
diff --git a/c64/basic/basic_main_loop.s b/c64/basic/basic_main_loop.s
index ef5c56dd..bfee34e6 100644
--- a/c64/basic/basic_main_loop.s
+++ b/c64/basic/basic_main_loop.s
@@ -24,7 +24,7 @@ read_line_loop:
 	ldx #22
 	jmp basic_do_error
 !:
-	sta basic_input_buffer,x
+	sta BUF,x
 	inx
 	jmp read_line_loop
 
diff --git a/c64/basic/cmd_list.s b/c64/basic/cmd_list.s
index 7c56e38e..b2e6e2a6 100644
--- a/c64/basic/cmd_list.s
+++ b/c64/basic/cmd_list.s
@@ -66,7 +66,7 @@ list_single_line: // entry point needed by DOS wedge
 	// Iterate through printing out the line
 	// contents
 	lda #0
-	sta quote_mode_flag
+	sta QTSW
 	
 	ldy #4
 list_print_loop:	
@@ -82,14 +82,14 @@ list_print_loop:
 	beq list_end_of_line
 	cmp #$22
 	bne list_not_quote
-	lda quote_mode_flag
+	lda QTSW
 	eor #$ff
-	sta quote_mode_flag
+	sta QTSW
 	lda #$22
 	jmp list_is_literal
 list_not_quote:	
 	// Check quote mode, and display as literal if required
-	ldx quote_mode_flag
+	ldx QTSW
 	bne list_is_literal
 	
 	cmp #$7f
@@ -128,7 +128,7 @@ list_not_quote:
 	// REM command locks quote flag on until the end of the line, allowing
 	// 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 QTSW    // Any value other than $00 or $FF will lock quote mode on, so the token value of REM is fine here
 	// FALL THROUGH
 list_not_rem:		
 	
diff --git a/c64/basic/tokenise_line.s b/c64/basic/tokenise_line.s
index 38e412b0..df2314af 100644
--- a/c64/basic/tokenise_line.s
+++ b/c64/basic/tokenise_line.s
@@ -17,7 +17,7 @@ tokenise_line:
 	lda #$00
 	sta $0110
 	sta $0112
-	sta quote_mode_flag
+	sta QTSW
 	
 	lda tokenise_work1
 	sta $0113
@@ -40,7 +40,7 @@ tokenise_char:
 
 	// Clear quote mode flag that is also used by KERNAL for screen display
 	lda #$00
-	sta quote_mode_flag
+	sta QTSW
 	rts
 !:
 	// More to do
@@ -60,9 +60,9 @@ tokenise_char_loop:
 	bne tk_not_quote
 
 	// Quote
-	lda quote_mode_flag
+	lda QTSW
 	eor #$ff
-	sta quote_mode_flag
+	sta QTSW
 	jmp tk_literal_char
 	
 tk_not_quote:
@@ -82,7 +82,7 @@ tk_not_quote:
 
 tk_might_be_keyword:	
 	// Don't tokenise in quote mode
-	lda quote_mode_flag
+	lda QTSW
 	bne tk_literal_char
 	
 	// Pack string
@@ -137,9 +137,9 @@ found_token_in_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:	
-	
+	sta QTSW
+not_rem:
+
 	// Now skip over the length of the token
 	lda $0110
 	clc
diff --git a/c64/kernal/,aliases.s b/c64/kernal/,aliases.s
index da75162a..286d92da 100644
--- a/c64/kernal/,aliases.s
+++ b/c64/kernal/,aliases.s
@@ -5,7 +5,6 @@
 
 // XXX get rid of this file, use ,aliases_ram_lowmem.s instead
 
-	.label kernal_load_or_verify_flag = $93
 	.label current_file_num = $98
 	.label input_device_number = DFLTN
 	.label cassette_buffer_bytes_used = $A6
@@ -30,7 +29,6 @@
 	.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
@@ -40,26 +38,6 @@
 	.label screen_line_link_table = $D9
 	.label current_screen_line_colour_ptr = $F3
 	.label keyboard_decoding_table_ptr = $F5
-	
-	// "Compute's Mapping the 64" book
-	.label keyboard_buffer = $0277
-	.label text_colour = $0286 // p55
-	.label colour_under_cursor = $0287 // p56
-	.label key_buffer_size = $0289 // p57
-
-	// 0 = cursor keys, insert, delete and space repeat, but nothing else
-	// 128 = all keys repeat
-	// 64 = no keys repeat
-	.label key_repeat_flags = $028A // p58
-	// https://www.c64-wiki.com/wiki/Page_2
-	.label key_repeat_counter = $028B
-	.label key_first_repeat_delay = $028C
-	// 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
 
 #if CONFIG_MEMORY_MODEL_60K
 
diff --git a/c64/kernal/blink_cursor.s b/c64/kernal/blink_cursor.s
index 3135b4bd..1f64e898 100644
--- a/c64/kernal/blink_cursor.s
+++ b/c64/kernal/blink_cursor.s
@@ -3,7 +3,7 @@
 // cursor_blink_countdown
 // cursor_saved_character
 // cursor_is_visible
-// colour_under_cursor
+// GDCOL (colour under cursor)
 
 show_cursor_if_enabled:
 	lda cursor_blink_disable
@@ -48,8 +48,8 @@ draw_cursor:
 	sta (current_screen_line_ptr),y
 	// Also set cursor colour
 	lda (current_screen_line_colour_ptr),y
-	sta colour_under_cursor
-	lda text_colour
+	sta GDCOL
+	lda COLOR
 	sta (current_screen_line_colour_ptr),y
 	
 	lda #1
@@ -63,7 +63,7 @@ undraw_cursor:
 	lda cursor_saved_character
 	ldy current_screen_x
 	sta (current_screen_line_ptr),y
-	lda colour_under_cursor
+	lda GDCOL
 	sta (current_screen_line_colour_ptr),y
 	
 	lda #0
diff --git a/c64/kernal/chrin_real.s b/c64/kernal/chrin_real.s
index fed6552d..741534e5 100644
--- a/c64/kernal/chrin_real.s
+++ b/c64/kernal/chrin_real.s
@@ -90,7 +90,7 @@ read_from_keyboard:
 	lda keys_in_key_buffer
 	beq chrin_repeat
 
-	lda keyboard_buffer
+	lda KEYD
 	cmp #$0d
 	bne not_enter
 
@@ -145,7 +145,7 @@ empty_line:
 
 not_enter:
 	// Print character
-	lda keyboard_buffer
+	lda KEYD
 	jsr CHROUT
 
 	jsr pop_keyboard_buffer
@@ -160,11 +160,11 @@ pop_keyboard_buffer:
 	sei
 	ldx #$00
 	ldy #$01
-!:	lda keyboard_buffer,y
-	sta keyboard_buffer,x
+!:	lda KEYD,y
+	sta KEYD,x
 	inx
 	iny
-	cpy key_buffer_size
+	cpy XMAX
 	bne !-
 	dec keys_in_key_buffer
 	cli
diff --git a/c64/kernal/chrout_real.s b/c64/kernal/chrout_real.s
index 190a4067..03d2b849 100644
--- a/c64/kernal/chrout_real.s
+++ b/c64/kernal/chrout_real.s
@@ -110,7 +110,7 @@ not_0a:
 	bne not_0d
 	// RETURN clears quote and insert modes
 	lda #$00
-	sta quote_mode_flag
+	sta QTSW
 	sta insert_mode
 	jmp screen_advance_to_next_line
 not_0d:
@@ -235,7 +235,7 @@ done_delete:
 not_14:
 
 	// Check for quote mode
-	ldx quote_mode_flag
+	ldx QTSW
 	bne is_quote_mode
 	ldx insert_mode
 	bne is_quote_mode
@@ -274,7 +274,7 @@ not_quote_mode:
 colour_check_loop:	
 	cmp colour_codes,x
 	bne !+
-	stx text_colour
+	stx COLOR
 	jmp chrout_done
 !:	dex
 	bpl colour_check_loop
@@ -415,14 +415,14 @@ output_literal_char:
 	bne not_quote
 
 	//  Toggle quote flag if required
-	lda quote_mode_flag
+	lda QTSW
 	eor #$80
-	sta quote_mode_flag
+	sta QTSW
 
 not_quote:
 
 	// Set colour
-	lda text_colour
+	lda COLOR
 	sta (current_screen_line_colour_ptr),y
 
 	// Advance the column, and scroll screen down if we need
@@ -556,7 +556,7 @@ no_copy_down:
 	// Erase newly inserted line
 	ldy #79
 !:
-	lda text_colour
+	lda COLOR
 	sta (current_screen_line_colour_ptr),y
 	lda #$20
 	sta (current_screen_line_ptr),y
@@ -659,7 +659,7 @@ scroll_copy_loop2:
 	// Fill in scrolled up area
 	ldx load_or_scroll_temp_pointer+0
 scroll_copy_loop3:
-	lda text_colour
+	lda COLOR
 	sta (current_screen_line_colour_ptr),y
 	lda #$20
 	sta (current_screen_line_ptr),y
diff --git a/c64/kernal/cint_real.s b/c64/kernal/cint_real.s
index 97a4d701..23452e08 100644
--- a/c64/kernal/cint_real.s
+++ b/c64/kernal/cint_real.s
@@ -79,17 +79,17 @@ cint_brk: // entry for BRK and STOP+RESTORE - XXX, where should it start?
 	// But require key to be held for ~1/3sec before
 	// repeating (Compute's Mapping the 64 p58)
 	ldx #22-2 		// Fudge factor to match speed
-	stx key_first_repeat_delay
+	stx DELAY
 
 	// Set current colour for text (Compute's Mapping the 64 p215)
 	ldx #$01     // default is light blue ($0E), but we use a different one
-	stx text_colour
+	stx COLOR
 
 	// 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
-	stx enable_case_switch
+	stx XMAX
+	// Put non-zero value in MODE to enable case switch
+	stx MODE
 	
 	// Set default I/O devices (see SCINIT description at http://sta.c64.org/cbm64krnfunc.html)
 	jsr clrchn_reset
diff --git a/c64/kernal/e544.clear_screen.s b/c64/kernal/e544.clear_screen.s
index d0e0e639..e699f2ec 100644
--- a/c64/kernal/e544.clear_screen.s
+++ b/c64/kernal/e544.clear_screen.s
@@ -47,7 +47,7 @@ clearscreen_l2:
 
 	// Clear colour RAM
 	// (Compute's Mapping the 64 p216)
-	lda text_colour
+	lda COLOR
 clearscreen_l3:	
 	sta $d800,y
 	sta $d900,y
diff --git a/c64/kernal/f13e.getin.s b/c64/kernal/f13e.getin.s
index 485535b0..c5f6b713 100644
--- a/c64/kernal/f13e.getin.s
+++ b/c64/kernal/f13e.getin.s
@@ -22,7 +22,7 @@ GETIN:
 	rts
 	
 !:
-	lda keyboard_buffer
+	lda KEYD
 	pha
 
 	jsr pop_keyboard_buffer
diff --git a/c64/kernal/fda3.ioinit.s b/c64/kernal/fda3.ioinit.s
index bdffec29..00fbf343 100644
--- a/c64/kernal/fda3.ioinit.s
+++ b/c64/kernal/fda3.ioinit.s
@@ -53,15 +53,15 @@ IOINIT:
 #endif // CONFIG_SID_D4XX || CONFIG_SID_D5XX
 
 #if CONFIG_SID_2ND
-	lda SID_SIGVOL - SID_BASE + CONFIG_SID_2ND_ADDRESS
+	lda SID_SIGVOL - __SID_BASE + CONFIG_SID_2ND_ADDRESS
 	and #$F0
-	sta SID_SIGVOL - SID_BASE + CONFIG_SID_2ND_ADDRESS
+	sta SID_SIGVOL - __SID_BASE + CONFIG_SID_2ND_ADDRESS
 #endif // CONFIG_SID_2ND
 
 #if CONFIG_SID_3RD
-	lda SID_SIGVOL - SID_BASE + CONFIG_SID_3RD_ADDRESS
+	lda SID_SIGVOL - __SID_BASE + CONFIG_SID_3RD_ADDRESS
 	and #$F0
-	sta SID_SIGVOL - SID_BASE + CONFIG_SID_3RD_ADDRESS
+	sta SID_SIGVOL - __SID_BASE + CONFIG_SID_3RD_ADDRESS
 #endif // CONFIG_SID_3RD
 
     // Initialize CIAs
diff --git a/c64/kernal/scnkey.s b/c64/kernal/scnkey.s
index 6bf96d90..31a587a4 100644
--- a/c64/kernal/scnkey.s
+++ b/c64/kernal/scnkey.s
@@ -74,9 +74,9 @@ SCNKEY:
 	sta BufferQuantity
 
 	// Decrement key repeat timeout if non-zero
-	ldx key_repeat_counter
+	ldx KOUNT
 	beq sk_start
-	dec key_repeat_counter
+	dec KOUNT
 	
 sk_start:	
 	// Call main keyboard scanning routine
@@ -110,7 +110,7 @@ accept_key:
 	// Convert matrix position to key code
 	// XXX - Add offset of $40, $80 or $C0 if shift, CONTROL or C= are held down
 	pha
-	lda key_bucky_state
+	lda SHFLAG
 	and #$7
 	tax
 	pla
@@ -123,9 +123,9 @@ accept_key:
 
 	// Stash key into keyboard buffer
 	ldx keys_in_key_buffer
-	cpx key_buffer_size
+	cpx XMAX
 	beq sk_nokey
-	sta keyboard_buffer,x
+	sta KEYD,x
 	inc keys_in_key_buffer
 	
 sk_nokey:	
@@ -204,10 +204,10 @@ ReturnNoKeys:
 NoActivityDetected:
 
 	// So cancel all bucky keys
-	lda key_bucky_state
-	sta key_last_bucky_state
+	lda SHFLAG
+	sta LSTSHF
 	lda #$00
-	sta key_bucky_state
+	sta SHFLAG
 	
 	jmp ReturnNoKeys
 
@@ -239,7 +239,7 @@ JoystickActivity:
 
 	// Clear bucky key status
 	lda #$00
-	sta key_bucky_state
+	sta SHFLAG
 	
 	lda $dc01
 	and #$03
@@ -254,7 +254,7 @@ JoystickActivity:
 	// Up
 	// Mark shift as pressed
 	ldx #$01
-	stx key_bucky_state
+	stx SHFLAG
 	ldx #$07		// UP/DOWN
 	jsr KeyFound
 !:
@@ -278,7 +278,7 @@ JoystickActivity:
 	cmp #$08
 	bne !+
 	ldx #$01
-	stx key_bucky_state
+	stx SHFLAG
 	ldx #$02
 	jsr KeyFound		// LEFT/RIGHT
 !:
@@ -332,20 +332,20 @@ next_row:
 
 	// Store de-bounce data for bucky keys
 	// (Compute's Mapping the 64, p58-59)
-	lda key_bucky_state
-	sta key_last_bucky_state
+	lda SHFLAG
+	sta LSTSHF
 
 	// Build bucky state
 	lda #$00
-	sta key_bucky_state
+	sta SHFLAG
 	lda ScanResult+6
 	eor #%10000000
 	and #%10000000     // Left shift
 	rol
 	rol
 	and #$01
-	ora key_bucky_state
-	sta key_bucky_state
+	ora SHFLAG
+	sta SHFLAG
 
 	// Right shift
 	lda ScanResult+1
@@ -355,15 +355,15 @@ next_row:
 	lsr
 	lsr
 	and #$01
-	ora key_bucky_state
-	sta key_bucky_state
+	ora SHFLAG
+	sta SHFLAG
 	
 	// Control
 	lda ScanResult+0
 	eor #$04
 	and #$04
-	ora key_bucky_state
-	sta key_bucky_state
+	ora SHFLAG
+	sta SHFLAG
 
 	// Vendor key
 	lda ScanResult+0
@@ -373,17 +373,17 @@ next_row:
 	lsr
 	lsr
 	and #$02
-	ora key_bucky_state
-	sta key_bucky_state
+	ora SHFLAG
+	sta SHFLAG
 
 	// Chick for shift + Vendor
 	cmp #$03
 	bne no_case_toggle
-	lda key_last_bucky_state
+	lda LSTSHF
 	cmp #$03
 	beq no_case_toggle
 
-	lda enable_case_switch
+	lda MODE
 	beq no_case_toggle
 	
 	lda $D018
@@ -509,15 +509,15 @@ KeyHeld:
 	// Different key held
 	sta last_key_matrix_position
 	pha
-	lda key_first_repeat_delay
-	sta key_repeat_counter
+	lda DELAY
+	sta KOUNT
 	pla
 BuckyHeld:
 	jmp ConsiderNextKey
 	
 SameKeyHeld:
 	pha
-	lda key_repeat_counter
+	lda KOUNT
 	bmi KeyCanRepeat
 	bne KeyRepeatWait
 	// Count down ended, so repeat key now
@@ -526,7 +526,7 @@ KeyCanRepeat:
 	// (Compute's Mapping the 64 p58)
 	pha
 	lda #6-2  		// Fudge factor to match speed
-	sta key_repeat_counter
+	sta KOUNT
 	pla
 	pla