700 lines
30 KiB
ArmAsm
700 lines
30 KiB
ArmAsm
* AUXMEM.SHR.S
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* (c) Bobbi 2022 GPLv3
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*
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* Routines for drawing bitmapped text and graphics in SHR mode
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* on Apple IIGS (640x200 4 colour, or 320x200 16 colour.)
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*
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SCB320 EQU $00 ; SCB for 320 mode
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SCB640 EQU $80 ; SCB for 640 mode
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* Colours in the following order.
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* For 16 colour modes ...
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* BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE, ...
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* For 4 colour modes ...
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* BLACK, RED, YELLOW, WHITE
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* GB 0R
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PALETTE320 DB $00, $00 ; BLACK
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DB $00, $0F ; RED
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DB $F0, $00 ; GREEN
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DB $F0, $0F ; YELLOW
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DB $0F, $00 ; BLUE
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DB $0F, $0F ; MAGENTA
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DB $FF, $00 ; CYAN
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DB $FF, $0F ; WHITE
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DB $44, $04 ; Dark grey
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DB $88, $0F ; RED (light)
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DB $F8, $08 ; GREEN (light)
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DB $F8, $0F ; YELLOW (light)
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DB $8F, $08 ; BLUE (light)
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DB $8F, $0F ; MAGENTA (light)
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DB $FF, $08 ; CYAN (light)
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DB $AA, $0A ; Light grey
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PALETTE640 DB $00, $00 ; BLACK
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DB $00, $0F ; RED
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DB $F0, $0F ; YELLOW
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DB $FF, $0F ; WHITE
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DB $00, $00 ; BLACK
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DB $00, $0F ; RED
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DB $F0, $0F ; YELLOW
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DB $F8, $0F ; WHITE
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DB $00, $00 ; BLACK
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DB $00, $0F ; RED
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DB $F0, $0F ; YELLOW
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DB $FF, $0F ; WHITE
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DB $00, $00 ; BLACK
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DB $00, $0F ; RED
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DB $F0, $0F ; YELLOW
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DB $FF, $0F ; WHITE
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* Addresses of start of text rows in SHR
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* LS byte is always zero
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* Add $A0 to get to next row of pixels
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SHRTAB DB $20 ; Text row 0
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DB $25 ; Text row 1
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DB $2a ; Text row 2
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DB $2f ; Text row 3
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DB $34 ; Text row 4
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DB $39 ; Text row 5
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DB $3e ; Text row 6
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DB $43 ; Text row 7
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DB $48 ; Text row 8
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DB $4d ; Text row 9
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DB $52 ; Text row 10
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DB $57 ; Text row 11
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DB $5c ; Text row 12
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DB $61 ; Text row 13
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DB $66 ; Text row 14
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DB $6b ; Text row 15
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DB $70 ; Text row 16
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DB $75 ; Text row 17
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DB $7a ; Text row 18
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DB $7f ; Text row 19
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DB $84 ; Text row 20
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DB $89 ; Text row 21
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DB $8e ; Text row 22
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DB $93 ; Text row 23
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* Enable SHR mode
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SHRVDU22 LDA #$18 ; Inhibit SHR & aux HGR shadowing
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TSB SHADOW
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LDA #$80 ; Most significant bit
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TSB NEWVIDEO ; Enable SHR mode
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LDA VDUPIXELS ; Pixels per byte
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CMP #$02 ; 2 is 320-mode (MODE 1)
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BNE :MODE0
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LDA #SCB320 ; SCB for 320-mode
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STZ CLR80VID ; 40 column text mode
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BRA :S1
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:MODE0 LDA #SCB640 ; SCB for 640-mode
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STZ SET80VID ; 80 column text mode
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:S1 LDX #$00
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:L1 STAL $E19D00,X ; SCBs begin at $9D00 in $E1
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INX
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CPX #200 ; 200 lines so 200 SCBs
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BNE :L1
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JSR SHRDEFPAL ; Default palette
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>>> XF2MAIN,SHRXPLDFONT ; Explode font -> SHRFONTXPLD table
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SHRV22RET >>> ENTAUX
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JSR VDU12 ; Clear text and SHR screen
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RTS
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******************************************************************************
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* Data in bank $E1
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******************************************************************************
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* Used for long writes
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SHRCOLMASKL EQU $E1B000 ; Colour mask foreground (word)
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SHRBGMASKL EQU $E1B002 ; Colour mask background (word)
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* Used for reads via data bank reg
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SHRCOLMASK EQU $B000 ; Colour mask foreground (word)
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SHRBGMASK EQU $B002 ; Colour mask background (word)
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******************************************************************************
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SHRBGMASKA DW $0000 ; Keep a copy in aux mem too
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* Write character to SHR screen
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* On entry: A - character to write
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SHRPRCHAR CMP CURSORED ; Edit cursor?
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BNE :NOTEDIT
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LDA #127 ; If so, use block char
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:NOTEDIT LDX VDUPIXELS ; Pixels per byte
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CPX #$02 ; 2 is 320-mode (MODE 1)
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BNE :S1
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JMP SHRPRCH320
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:S1 JMP SHRPRCH640
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* Write character to SHR screen in 320 pixel mode
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SHRPRCH320 SEC
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SBC #32
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STA VDUADDR2+0 ; A*32 -> VDUADDR2
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STZ VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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CLC ; SHRFONTXPLD+A*32 -> VDUADDR2
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LDA VDUADDR2+0
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ADC #<SHRFONTXPLD
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STA VDUADDR2+0
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LDA VDUADDR2+1
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ADC #>SHRFONTXPLD
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STA VDUADDR2+1
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LDA #$E1
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STA VDUBANK2
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JSR SHRCHARADDR ; Screen addr in VDUADDR
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* 65816 code contributed by John Brooks follows ...
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PHP ; Disable interrupts
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SEI
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PHB ; Save data bank
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LDA VDUBANK2 ; Push font Bank onto stack
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PHA
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PLB ; Set data bank to font bank
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CLC ; 65816 native mode
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XCE
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REP #$30 ; 16 bit M & X
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MX %00 ; Tell Merlin
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LDY VDUADDR2 ; Font src ptr
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LDX VDUADDR ; SHR dst ptr
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LDA !$000000,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10000,X ; Write 2 bytes to screen
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LDA !$000002,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10002,X ; Write 2 bytes to screen
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LDA !$000004,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E100A0,X ; Write 2 bytes to screen
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LDA !$000006,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E100A2,X ; Write 2 bytes to screen
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LDA !$000008,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10140,X ; Write 2 bytes to screen
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LDA !$00000A,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10142,X ; Write 2 bytes to screen
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LDA !$00000C,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E101E0,X ; Write 2 bytes to screen
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LDA !$00000E,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E101E2,X ; Write 2 bytes to screen
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LDA !$000010,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10280,X ; Write 2 bytes to screen
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LDA !$000012,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10282,X ; Write 2 bytes to screen
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LDA !$000014,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10320,X ; Write 2 bytes to screen
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LDA !$000016,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10322,X ; Write 2 bytes to screen
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LDA !$000018,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E103C0,X ; Write 2 bytes to screen
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LDA !$00001A,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E103C2,X ; Write 2 bytes to screen
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LDA !$00001C,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10460,X ; Write 2 bytes to screen
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LDA !$00001E,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10462,X ; Write 2 bytes to screen
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PLB ; Recover data bank
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SEC ; Back to emulation mode
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XCE
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MX %11 ; Tell Merlin
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PLP ; Normal service resumed
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RTS
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* Write character to SHR screen in 640 pixel mode
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SHRPRCH640 SEC
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SBC #32
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STA VDUADDR2+0 ; A*16 -> VDUADDR2
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STZ VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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ASL VDUADDR2+0
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ROL VDUADDR2+1
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CLC ; SHRFONTXPLD+A*16 -> VDUADDR2
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LDA VDUADDR2+0
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ADC #<SHRFONTXPLD
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STA VDUADDR2+0
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LDA VDUADDR2+1
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ADC #>SHRFONTXPLD
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STA VDUADDR2+1
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LDA #$E1
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STA VDUBANK2
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JSR SHRCHARADDR ; Screen addr in VDUADDR
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* 65816 code contributed by John Brooks follows ...
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PHP ; Disable interrupts
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SEI
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PHB ; Save data bank
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LDA VDUBANK2 ; Push font Bank onto stack
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PHA
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PLB ; Set data bank to font bank
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CLC ; 65816 native mode
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XCE
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REP #$30 ; 16 bit M & X
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MX %00 ; Tell Merlin
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LDY VDUADDR2 ; Font src ptr
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LDX VDUADDR ; SHR dst ptr
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LDA !$000000,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10000,X ; Write 2 bytes to screen
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LDA !$000002,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E100A0,X ; Write 2 bytes to screen
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LDA !$000004,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10140,X ; Write 2 bytes to screen
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LDA !$000006,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E101E0,X ; Write 2 bytes to screen
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LDA !$000008,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10280,X ; Write 2 bytes to screen
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LDA !$00000A,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10320,X ; Write 2 bytes to screen
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LDA !$00000C,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E103C0,X ; Write 2 bytes to screen
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LDA !$00000E,Y ; Read 2 bytes of exploded font
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JSR SHRCOLWORD
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STAL $E10460,X ; Write 2 bytes to screen
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PLB ; Recover data bank
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SEC ; Back to emulation mode
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XCE
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MX %11 ; Tell Merlin
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PLP ; Normal service resumed
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RTS
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* Apply colour masks to 16 bit word of character data
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* Called in 65816 native mode, 16 bit
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SHRCOLWORD MX %00 ; Tell Merlin 16 bit M & X
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PHA ; Keep A
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AND SHRCOLMASK ; Mask to set foreground colour
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STA ZP1 ; Keep foreground
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PLA ; Get original A back
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EOR #$FFFF ; Invert bits
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AND SHRBGMASK ; Apply background colour mask
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EOR ZP1 ; Combine with foreground
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RTS
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MX %11
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* Calculate character address in SHR screen memory
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* This is the address of the first pixel row of the char
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* Add $00A0 for each subsequent row
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SHRCHARADDR LDY VDUTEXTY
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LDA SHRTAB,Y ; MSB
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STA VDUADDR+1
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LDA VDUTEXTX
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ASL ; Mult x 2 (4 pixels/byte)
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LDY VDUPIXELS ; Pixels per byte
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CPY #$02 ; 2 pixels per byte in 320 mode
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BNE :S1
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ASL ; Mult x 2 (2 pixels/byte)
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:S1 STA VDUADDR+0 ; LSB of address
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LDA #$E1 ; Bank $E1
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STA VDUBANK
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RTS
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* (VDUADDR)=>character address, X=preserved
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* Advance VDUADDR to the next row of pixels
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SHRNEXTROW LDA VDUADDR+0 ; Add 160 to VDUADDR
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CLC
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ADC #160
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STA VDUADDR+0
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LDA VDUADDR+1
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ADC #$00
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STA VDUADDR+1
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RTS
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* Forwards scroll one line
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* Copy text line A+1 to line A
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* Note: Code for this courtesy Kent Dickey
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SHRSCR1LINE PHY
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PHX
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STA VDUADDR+1 ; Screen line -> MSB
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STZ VDUADDR+0 ; Zero LSB
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PHP ; Disable interrupts
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SEI
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CLC ; Enter native mode
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XCE
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PHB ; Preserve data bank
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REP #$31 ; M,X 16 bit, carry clear
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MX %00 ; Tell Merlin
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LDA VDUADDR ; Screen line to scroll
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ASL ; Mult 4
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ASL
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ADC VDUADDR ; Mult 5
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STA VDUADDR ; VDUADDR = line * $500
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LDA TXTWINLFT ; Left margin
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LDY VDUPIXELS ; Pixels per byte
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CPY #$02 ; 2 pixels per byte in 320 mode
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BNE :S1
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ASL ; Double TXTWINLFT
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:S1 ASL ; 2 bytes / char
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AND #$00ff ; Mask to get 8 bit result
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ADC VDUADDR ; Add to beginning of line addr
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STA VDUADDR ; VDUADDR = start position
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SEP #$21 ; M 8 bit, X 16 bit, carry set
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MX %10 ; Tell Merlin
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LDA TXTWINRGT ; Compute width ..
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SBC TXTWINLFT ; .. right minus left
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LDY VDUPIXELS ; Pixels per byte
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CPY #$02 ; 2 pixels per byte in 320 mode
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BNE :S2
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ASL ; Double the width for 320
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INC A ; Plus one
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:S2 REP #$31 ; M,X 16 bit, carry clear
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MX %00 ; Tell Merlin
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ASL ; 2 bytes / char
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AND #$00ff ; Mask to get 8 bit result
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ADC VDUADDR ; Add to start position
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TAX ; Will use as index
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PEA #$E1E1 ; Set databank to $E1
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PLB
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PLB
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:LOOP1 LDA $2500,X ; 2 bytes, row 0
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STA $2000,X
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LDA $25A0,X ; row 1
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STA $20A0,X
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LDA $2640,X ; row 2
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STA $2140,X
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LDA $26E0,X ; row 3
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STA $21E0,X
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LDA $2780,X ; row 4
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STA $2280,X
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LDA $2820,X ; row 5
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STA $2320,X
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LDA $28C0,X ; row 6
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STA $23C0,X
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LDA $2960,X ; row 7
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STA $2460,X
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DEX ; Update index
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DEX
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BMI :DONE ; Jump out if odd->-ve
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CPX VDUADDR ; Compare with start addr
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BCS :LOOP1 ; Bytes left? Go again
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:DONE PLB ; Recover data bank
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SEC ; Back to emulation mode
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XCE
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PLP ; Recover flags + regs
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PLX
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PLY
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RTS
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* Reverse scroll one line
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* Copy text line A to line A+1
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SHRRSCR1LINE PHY
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PHX
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STA VDUADDR+1 ; Screen line -> MSB
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STZ VDUADDR+0 ; Zero LSB
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PHP ; Disable interrupts
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SEI
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CLC ; Enter native mode
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XCE
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PHB ; Preserve data bank
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REP #$31 ; M,X 16 bit, carry clear
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MX %00 ; Tell Merlin
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LDA VDUADDR ; Screen line to scroll
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ASL ; Mult 4
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ASL
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ADC VDUADDR ; Mult 5
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STA VDUADDR ; VDUADDR = line * $500
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LDA TXTWINLFT ; Left margin
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LDY VDUPIXELS ; Pixels per byte
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CPY #$02 ; 2 pixels per byte in 320 mode
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BNE :S1
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ASL ; Double TXTWINLFT
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:S1 ASL ; 2 bytes / char
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AND #$00ff ; Mask to get 8 bit result
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ADC VDUADDR ; Add to beginning of line addr
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STA VDUADDR ; VDUADDR = start position
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SEP #$21 ; M 8 bit, X 16 bit, carry set
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MX %10 ; Tell Merlin
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LDA TXTWINRGT ; Compute width ..
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SBC TXTWINLFT ; .. right minus left
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LDY VDUPIXELS ; Pixels per byte
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CPY #$02 ; 2 pixels per byte in 320 mode
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BNE :S2
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ASL ; Double the width for 320
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INC A ; Plus one
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:S2 REP #$31 ; M,X 16 bit, carry clear
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MX %00 ; Tell Merlin
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ASL ; 2 bytes / char
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AND #$00ff ; Mask to get 8 bit result
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ADC VDUADDR ; Add to start position
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TAX ; Will use as index
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PEA #$E1E1 ; Set databank to $E1
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PLB
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PLB
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:LOOP1 LDA $2000,X ; 2 bytes, row 0
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STA $2500,X
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LDA $20A0,X ; row 1
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STA $25A0,X
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LDA $2140,X ; row 2
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STA $2640,X
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LDA $21E0,X ; row 3
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STA $26E0,X
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LDA $2280,X ; row 4
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STA $2780,X
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LDA $2320,X ; row 5
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STA $2820,X
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LDA $23C0,X ; row 6
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STA $28C0,X
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LDA $2460,X ; row 7
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STA $2960,X
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DEX ; Update index
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DEX
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BMI :DONE ; Jump out if odd->-ve
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CPX VDUADDR ; Compare with start addr
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BCS :LOOP1 ; Bytes left? Go again
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:DONE PLB ; Recover data bank
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SEC ; Back to emulation mode
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XCE
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PLP ; Recover flags + regs
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PLX
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PLY
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RTS
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* Clear from current location to EOL
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SHRCLREOL JSR SHRCHARADDR
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STZ VDUADDR+0 ; Addr of start of line
|
|
LDA #$08 ; Eight rows of pixels
|
|
STA :CTR
|
|
INC TXTWINRGT
|
|
:L0 LDA VDUTEXTX
|
|
TAX
|
|
ASL ; 2 bytes / char
|
|
LDY VDUPIXELS ; Pixels per byte
|
|
CPY #$02 ; 2 is 320-mode (MODE 1)
|
|
BNE :S0
|
|
ASL ; 4 bytes / char
|
|
:S0 TAY
|
|
:L1 CPX TXTWINRGT
|
|
BCS :S1
|
|
LDA SHRBGMASKA
|
|
STA [VDUADDR],Y
|
|
INY
|
|
STA [VDUADDR],Y
|
|
INY
|
|
LDA VDUPIXELS ; Pixels per byte
|
|
CMP #$02 ; 2 is 320-mode (MODE 1)
|
|
BNE :S2
|
|
LDA SHRBGMASKA
|
|
STA [VDUADDR],Y
|
|
INY
|
|
STA [VDUADDR],Y
|
|
INY
|
|
:S2 INX
|
|
BRA :L1
|
|
:S1 JSR SHRNEXTROW
|
|
DEC :CTR
|
|
BNE :L0
|
|
DEC TXTWINRGT
|
|
RTS
|
|
:CTR DB $00
|
|
|
|
|
|
* VDU16 (CLG) clears the whole SHR screen right now
|
|
SHRCLEAR PHP ; Disable interrupts
|
|
SEI
|
|
CLC ; 816 native mode
|
|
XCE
|
|
REP #$10 ; 16 bit index
|
|
MX %10 ; Tell Merlin
|
|
LDX #$0000
|
|
LDA #$00
|
|
:L1 STAL $E12000,X ; SHR screen @ E1:2000
|
|
INX
|
|
CPX #$7D00
|
|
BNE :L1
|
|
SEP #$10 ; Back to 8 bit index
|
|
MX %11 ; Tell Merlin
|
|
SEC ; Back to 6502 emu mode
|
|
XCE
|
|
PLP ; Normal service resumed
|
|
RTS
|
|
|
|
|
|
* Set text colour
|
|
* A=txt colour
|
|
SHRSETTCOL BIT VDUBANK ; Check it is a GS ..
|
|
BMI :GS ; .. easier to check here
|
|
RTS
|
|
:GS PHA
|
|
LDX VDUPIXELS ; Pixels per byte
|
|
CPX #$02 ; 2 is 320-mode (MODE 1)
|
|
BNE :MODE0
|
|
AND #$80
|
|
BEQ :FORE320
|
|
PLA
|
|
AND #$0F
|
|
TAX
|
|
LDA :MASKS320,X ; Lookup mask in table
|
|
STAL SHRBGMASKL ; Set colour mask (BG)
|
|
STAL SHRBGMASKL+1
|
|
STA SHRBGMASKA
|
|
RTS
|
|
:FORE320 PLA
|
|
AND #$0F
|
|
TAX
|
|
LDA :MASKS320,X ; Lookup mask in table
|
|
STAL SHRCOLMASKL ; Set colour mask (FG)
|
|
STAL SHRCOLMASKL+1
|
|
RTS
|
|
:MODE0 AND #$80
|
|
BEQ :FORE640
|
|
PLA
|
|
AND #$03
|
|
TAX
|
|
LDA :MASKS640,X ; Lookup mask in table
|
|
STAL SHRBGMASKL ; Set colour mask (BG)
|
|
STAL SHRBGMASKL+1
|
|
STA SHRBGMASKA
|
|
RTS
|
|
:FORE640 PLA
|
|
AND #$03
|
|
TAX
|
|
LDA :MASKS640,X ; Lookup mask in table
|
|
STAL SHRCOLMASKL ; Set colour mask (FG)
|
|
STAL SHRCOLMASKL+1
|
|
RTS
|
|
:MASKS640 DB %00000000
|
|
DB %01010101
|
|
DB %10101010
|
|
DB %11111111
|
|
:MASKS320 DB $00
|
|
DB $11
|
|
DB $22
|
|
DB $33
|
|
DB $44
|
|
DB $55
|
|
DB $66
|
|
DB $77
|
|
DB $88
|
|
DB $99
|
|
DB $AA
|
|
DB $BB
|
|
DB $CC
|
|
DB $DD
|
|
DB $EE
|
|
DB $FF
|
|
|
|
|
|
* Set up default palette
|
|
SHRDEFPAL LDY #00 ; Palette offset for 320 mode
|
|
LDA VDUPIXELS ; Pixels per byte
|
|
CMP #$02 ; 2 is 320-mode (MODE 1)
|
|
BEQ :S1
|
|
LDY #32 ; Palette offset for 640 mode
|
|
:S1 LDX #$00
|
|
:L1 LDA PALETTE320,Y ; Offset in Y computed above
|
|
STAL $E19E00,X ; Palettes begin at $9E00 in $E1
|
|
INX
|
|
INY
|
|
CPX #32 ; 32 bytes in palette
|
|
BNE :L1
|
|
RTS
|
|
|
|
|
|
* Assign a 'physical' colour from the 16 colour palette to a
|
|
* 'logical' colour for the current mode
|
|
* On entry: X=logical colour, Y=physical colour
|
|
SHRPALCHANGE TYA
|
|
AND #%00011110 ; Has already been shifted
|
|
TAY
|
|
LDA VDUPIXELS ; Pixels per byte
|
|
CMP #$02 ; 2 is 320-mode (MODE 1)
|
|
BEQ :MODE320
|
|
TXA
|
|
AND #%00000110 ; Has already been shifted
|
|
TAX
|
|
LDA PALETTE320,Y ; Byte 1 of physical colour
|
|
STAL $E19E00,X ; Store in logical slot (4 copies)
|
|
STAL $E19E00+8,X
|
|
STAL $E19E00+16,X
|
|
STAL $E19E00+24,X
|
|
LDA PALETTE320+1,Y ; Byte 2 of physical colour
|
|
STAL $E19E00+1,X ; Store in logical slot (4 copies)
|
|
STAL $E19E00+9,X
|
|
STAL $E19E00+17,X
|
|
STAL $E19E00+25,X
|
|
RTS
|
|
:MODE320 TXA
|
|
AND #%00011110 ; Has already been shifted
|
|
TAX
|
|
LDA PALETTE320,Y ; Byte 1 of physical colour
|
|
STAL $E19E00,X ; Store in logical slot
|
|
LDA PALETTE320+1,Y ; Byte 2 of physical colour
|
|
STAL $E19E00+1,X ; Store in logical slot
|
|
RTS
|
|
|
|
|
|
* Assign a custom RGB colour to a 'logical' colour
|
|
* On entry: X=logical colour, A=GB components, Y=R component
|
|
SHRPALCUSTOM PHA ; Preserve GB components
|
|
LDA VDUPIXELS ; Pixels per byte
|
|
CMP #$02 ; 2 is 320-mode (MODE 1)
|
|
BEQ :MODE320
|
|
TXA
|
|
AND #%00000110 ; Has already been shifted
|
|
TAX
|
|
PLA ; Recover GB components
|
|
STAL $E19E00,X ; Store in logical slot (4 copies)
|
|
STAL $E19E00+8,X
|
|
STAL $E19E00+16,X
|
|
STAL $E19E00+24,X
|
|
TYA ; R component
|
|
STAL $E19E00+1,X ; Store in logical slot (4 copies)
|
|
STAL $E19E00+9,X
|
|
STAL $E19E00+17,X
|
|
STAL $E19E00+25,X
|
|
RTS
|
|
:MODE320 TXA
|
|
AND #%00011110 ; Has already been shifted
|
|
TAX
|
|
PLA ; Recover GB components
|
|
STAL $E19E00,X ; Store in logical slot
|
|
TYA ; R component
|
|
STAL $E19E00+1,X ; Store in logical slot
|
|
RTS
|
|
|