* AUXMEM.SHR.S * (c) Bobbi 2022 GPLv3 * * Routines for drawing bitmapped text and graphics in SHR mode * on Apple IIGS (640x200 4 colour, or 320x200 16 colour.) * SCB320 EQU $00 ; SCB for 320 mode SCB640 EQU $80 ; SCB for 640 mode * Pixel masks for colours in 640 mode SHRCMASK640 DB %00000000 DB %01010101 DB %10101010 DB %11111111 * Pixel masks for colours in 320 mode SHRCMASK320 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 * Addresses of start of text rows in SHR * LS byte is always zero * Add $A0 to get to next row of pixels SHRTAB DB $20 ; Text row 0 DB $25 ; Text row 1 DB $2a ; Text row 2 DB $2f ; Text row 3 DB $34 ; Text row 4 DB $39 ; Text row 5 DB $3e ; Text row 6 DB $43 ; Text row 7 DB $48 ; Text row 8 DB $4d ; Text row 9 DB $52 ; Text row 10 DB $57 ; Text row 11 DB $5c ; Text row 12 DB $61 ; Text row 13 DB $66 ; Text row 14 DB $6b ; Text row 15 DB $70 ; Text row 16 DB $75 ; Text row 17 DB $7a ; Text row 18 DB $7f ; Text row 19 DB $84 ; Text row 20 DB $89 ; Text row 21 DB $8e ; Text row 22 DB $93 ; Text row 23 * Enable SHR mode SHRVDU22 LDA #$18 ; Inhibit SHR & aux HGR shadowing TSB SHADOW LDA #$80 ; Most significant bit TSB NEWVIDEO ; Enable SHR mode LDA VDUPIXELS ; Pixels per byte CMP #$02 ; 2 is 320-mode (MODE 1) BNE :MODE0 LDA #SCB320 ; SCB for 320-mode STZ CLR80VID ; 40 column text mode BRA :S1 :MODE0 LDA #SCB640 ; SCB for 640-mode STZ SET80VID ; 80 column text mode :S1 LDX #$00 :L1 STAL $E19D00,X ; SCBs begin at $9D00 in $E1 INX CPX #200 ; 200 lines so 200 SCBs BNE :L1 JSR SHRDEFPAL ; Default palette >>> XF2MAIN,SHRXPLDFONT ; Explode font -> SHRFONTXPLD table SHRV22RET >>> ENTAUX JSR VDU12 ; Clear text and SHR screen RTS ****************************************************************************** * Data in bank $E1 ****************************************************************************** * Used for long writes SHRCOLMASKL EQU $E1B000 ; Colour mask foreground (word) SHRBGMASKL EQU $E1B002 ; Colour mask background (word) * Used for reads via data bank reg SHRCOLMASK EQU $B000 ; Colour mask foreground (word) SHRBGMASK EQU $B002 ; Colour mask background (word) ****************************************************************************** SHRBGMASKA DW $0000 ; Keep a copy in aux mem too * Write character to SHR screen * On entry: A - character to write SHRPRCHAR LDX VDUPIXELS ; Pixels per byte CPX #$02 ; 2 is 320-mode (MODE 1) BNE :S1 JMP SHRPRCH320 :S1 JMP SHRPRCH640 * Plot or unplot a cursor on SHR screen * On entry: A - character to plot, * CS show cursor / CC remove cursor * VS read cursor / VC write cursor * The read and write cursors have separate save-unders in :SAVEBYTES SHRCURSOR PHP ; Preserve flags PHA ; Preserve A LDA VDUSTATUS ; If VDU5 mode, bail AND #$20 BNE SHRCURSBAIL JSR SHRCHARADDR ; Screen addr in VDUADDR >>> WRTMAIN LDA VDUADDR+0 ; Copy addr to SHRVDUQ STA SHRVDUQ+0 LDA VDUADDR+1 STA SHRVDUQ+1 >>> WRTAUX PLA ; Recover A PLY ; Flags -> Y >>> XF2MAIN,SHRCURSM SHRCURSRET >>> ENTAUX RTS SHRCURSBAIL PLA PLP RTS * Write character to SHR screen in 320 pixel mode SHRPRCH320 SEC SBC #32 TAX LDA VDUSTATUS AND #$20 ; Bit 5 text@gfx cursor BEQ SHRPRCH320V4 ; VDU 4 TXA >>> XF2MAIN,SHRVDU5CH ; VDU5 SHRPRCH320RET >>> ENTAUX RTS SHRPRCH320V4 TXA CLC ; 65816 native mode XCE REP #$30 ; 16 bit M & X MX %00 ; Tell Merlin AND #$00FF STA VDUADDR2 ; A*32 -> VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 CLC ; SHRFONTXPLD+A*32 -> VDUADDR2 LDA VDUADDR2 ADC #SHRFONTXPLD STA VDUADDR2 SEP #$30 ; 8 bit M & X MX %11 ; Tell Merlin LDA #$E1 STA VDUBANK2 JSR SHRCHARADDR ; Screen addr in VDUADDR * 65816 code contributed by John Brooks follows ... PHB ; Save data bank LDA VDUBANK2 ; Push font Bank onto stack PHA PLB ; Set data bank to font bank REP #$30 ; 16 bit M & X MX %00 ; Tell Merlin LDY VDUADDR2 ; Font src ptr LDX VDUADDR ; SHR dst ptr LDA !$000000,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10000,X ; Write 2 bytes to screen LDA !$000002,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10002,X ; Write 2 bytes to screen LDA !$000004,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E100A0,X ; Write 2 bytes to screen LDA !$000006,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E100A2,X ; Write 2 bytes to screen LDA !$000008,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10140,X ; Write 2 bytes to screen LDA !$00000A,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10142,X ; Write 2 bytes to screen LDA !$00000C,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E101E0,X ; Write 2 bytes to screen LDA !$00000E,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E101E2,X ; Write 2 bytes to screen LDA !$000010,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10280,X ; Write 2 bytes to screen LDA !$000012,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10282,X ; Write 2 bytes to screen LDA !$000014,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10320,X ; Write 2 bytes to screen LDA !$000016,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10322,X ; Write 2 bytes to screen LDA !$000018,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E103C0,X ; Write 2 bytes to screen LDA !$00001A,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E103C2,X ; Write 2 bytes to screen LDA !$00001C,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10460,X ; Write 2 bytes to screen LDA !$00001E,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10462,X ; Write 2 bytes to screen PLB ; Recover data bank SEC ; Back to emulation mode XCE MX %11 ; Tell Merlin RTS * Write character to SHR screen in 640 pixel mode SHRPRCH640 SEC SBC #32 TAX LDA VDUSTATUS AND #$20 ; Bit 5 text@gfx cursor BEQ SHRPRCH640V4 ; VDU 4 TXA >>> XF2MAIN,SHRVDU5CH ; VDU5 * (Returns via SHRPRCH320RET) SHRPRCH640V4 TXA CLC ; 65816 native mode XCE REP #$30 ; 16 bit M & X MX %00 ; Tell Merlin AND #$00FF STA VDUADDR2 ; A*16 -> VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 ASL VDUADDR2 CLC ; SHRFONTXPLD+A*16 -> VDUADDR2 LDA VDUADDR2 ADC #SHRFONTXPLD STA VDUADDR2 SEP #$30 ; 8 bit M & X MX %11 ; Tell Merlin LDA #$E1 STA VDUBANK2 JSR SHRCHARADDR ; Screen addr in VDUADDR * 65816 code contributed by John Brooks follows ... PHB ; Save data bank LDA VDUBANK2 ; Push font Bank onto stack PHA PLB ; Set data bank to font bank REP #$30 ; 16 bit M & X MX %00 ; Tell Merlin LDY VDUADDR2 ; Font src ptr LDX VDUADDR ; SHR dst ptr LDA !$000000,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10000,X ; Write 2 bytes to screen LDA !$000002,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E100A0,X ; Write 2 bytes to screen LDA !$000004,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10140,X ; Write 2 bytes to screen LDA !$000006,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E101E0,X ; Write 2 bytes to screen LDA !$000008,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10280,X ; Write 2 bytes to screen LDA !$00000A,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10320,X ; Write 2 bytes to screen LDA !$00000C,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E103C0,X ; Write 2 bytes to screen LDA !$00000E,Y ; Read 2 bytes of exploded font JSR SHRCOLWORD STAL $E10460,X ; Write 2 bytes to screen PLB ; Recover data bank SEC ; Back to emulation mode XCE MX %11 ; Tell Merlin RTS * Apply colour masks to 16 bit word of character data * Called in 65816 native mode, 16 bit SHRCOLWORD MX %00 ; Tell Merlin 16 bit M & X PHA ; Keep A AND SHRCOLMASK ; Mask to set foreground colour STA ZP1 ; Keep foreground PLA ; Get original A back EOR #$FFFF ; Invert bits AND SHRBGMASK ; Apply background colour mask EOR ZP1 ; Combine with foreground RTS MX %11 * Calculate character address in SHR screen memory * This is the address of the first pixel row of the char * Add $00A0 for each subsequent row SHRCHARADDR LDY VDUTEXTY LDA SHRTAB,Y ; MSB STA VDUADDR+1 LDA VDUTEXTX ASL ; Mult x 2 (4 pixels/byte) LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 pixels per byte in 320 mode BNE :S1 ASL ; Mult x 2 (2 pixels/byte) :S1 STA VDUADDR+0 ; LSB of address LDA #$E1 ; Bank $E1 STA VDUBANK RTS * (VDUADDR)=>character address, X=preserved * Advance VDUADDR to the next row of pixels SHRNEXTROW LDA VDUADDR+0 ; Add 160 to VDUADDR CLC ADC #160 STA VDUADDR+0 LDA VDUADDR+1 ADC #$00 STA VDUADDR+1 RTS * Forwards scroll one line * Copy text line A+1 to line A * Note: Code for this courtesy Kent Dickey SHRSCR1LINE PHY PHX STA VDUADDR+1 ; Screen line -> MSB STZ VDUADDR+0 ; Zero LSB CLC ; Enter native mode XCE PHB ; Preserve data bank REP #$31 ; M,X 16 bit, carry clear MX %00 ; Tell Merlin LDA VDUADDR ; Screen line to scroll ASL ; Mult 4 ASL ADC VDUADDR ; Mult 5 STA VDUADDR ; VDUADDR = line * $500 LDA TXTWINLFT ; Left margin LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 pixels per byte in 320 mode BNE :S1 ASL ; Double TXTWINLFT :S1 ASL ; 2 bytes / char AND #$00ff ; Mask to get 8 bit result ADC VDUADDR ; Add to beginning of line addr STA VDUADDR ; VDUADDR = start position SEP #$21 ; M 8 bit, X 16 bit, carry set MX %10 ; Tell Merlin LDA TXTWINRGT ; Compute width .. SBC TXTWINLFT ; .. right minus left LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 pixels per byte in 320 mode BNE :S2 ASL ; Double the width for 320 INC A ; Plus one :S2 REP #$31 ; M,X 16 bit, carry clear MX %00 ; Tell Merlin ASL ; 2 bytes / char AND #$00ff ; Mask to get 8 bit result ADC VDUADDR ; Add to start position TAX ; Will use as index PEA #$E1E1 ; Set databank to $E1 PLB PLB :LOOP1 LDA $2500,X ; 2 bytes, row 0 STA $2000,X LDA $25A0,X ; row 1 STA $20A0,X LDA $2640,X ; row 2 STA $2140,X LDA $26E0,X ; row 3 STA $21E0,X LDA $2780,X ; row 4 STA $2280,X LDA $2820,X ; row 5 STA $2320,X LDA $28C0,X ; row 6 STA $23C0,X LDA $2960,X ; row 7 STA $2460,X DEX ; Update index DEX BMI :DONE ; Jump out if odd->-ve CPX VDUADDR ; Compare with start addr BCS :LOOP1 ; Bytes left? Go again :DONE PLB ; Recover data bank SEC ; Back to emulation mode XCE PLX PLY RTS * Reverse scroll one line * Copy text line A to line A+1 SHRRSCR1LINE PHY PHX STA VDUADDR+1 ; Screen line -> MSB STZ VDUADDR+0 ; Zero LSB CLC ; Enter native mode XCE PHB ; Preserve data bank REP #$31 ; M,X 16 bit, carry clear MX %00 ; Tell Merlin LDA VDUADDR ; Screen line to scroll ASL ; Mult 4 ASL ADC VDUADDR ; Mult 5 STA VDUADDR ; VDUADDR = line * $500 LDA TXTWINLFT ; Left margin LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 pixels per byte in 320 mode BNE :S1 ASL ; Double TXTWINLFT :S1 ASL ; 2 bytes / char AND #$00ff ; Mask to get 8 bit result ADC VDUADDR ; Add to beginning of line addr STA VDUADDR ; VDUADDR = start position SEP #$21 ; M 8 bit, X 16 bit, carry set MX %10 ; Tell Merlin LDA TXTWINRGT ; Compute width .. SBC TXTWINLFT ; .. right minus left LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 pixels per byte in 320 mode BNE :S2 ASL ; Double the width for 320 INC A ; Plus one :S2 REP #$31 ; M,X 16 bit, carry clear MX %00 ; Tell Merlin ASL ; 2 bytes / char AND #$00ff ; Mask to get 8 bit result ADC VDUADDR ; Add to start position TAX ; Will use as index PEA #$E1E1 ; Set databank to $E1 PLB PLB :LOOP1 LDA $2000,X ; 2 bytes, row 0 STA $2500,X LDA $20A0,X ; row 1 STA $25A0,X LDA $2140,X ; row 2 STA $2640,X LDA $21E0,X ; row 3 STA $26E0,X LDA $2280,X ; row 4 STA $2780,X LDA $2320,X ; row 5 STA $2820,X LDA $23C0,X ; row 6 STA $28C0,X LDA $2460,X ; row 7 STA $2960,X DEX ; Update index DEX BMI :DONE ; Jump out if odd->-ve CPX VDUADDR ; Compare with start addr BCS :LOOP1 ; Bytes left? Go again :DONE PLB ; Recover data bank SEC ; Back to emulation mode XCE PLX PLY RTS * Clear from current location to EOL SHRCLREOL JSR SHRCHARADDR 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 graphics window SHRCLEAR >>> XF2MAIN,SHRVDU16 SHRCLRRET >>> ENTAUX RTS * Set text colour * A=text colour SHRSETTCOL 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 SHRCMASK320,X ; Lookup mask in table STAL SHRBGMASKL ; Set colour mask (BG) STAL SHRBGMASKL+1 STA SHRBGMASKA RTS :FORE320 PLA AND #$0F TAX LDA SHRCMASK320,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 SHRCMASK640,X ; Lookup mask in table STAL SHRBGMASKL ; Set colour mask (BG) STAL SHRBGMASKL+1 STA SHRBGMASKA RTS :FORE640 PLA AND #$03 TAX LDA SHRCMASK640,X ; Lookup mask in table STAL SHRCOLMASKL ; Set colour mask (FG) STAL SHRCOLMASKL+1 RTS * Set graphics colour * A=gfx colour, X=gcol action * GCOL actions: * 0 = SET pixel * 1 = ORA with pixel * 2 = AND with pixel * 3 = XOR with pixel * 4 = NOT pixel * 5 = NUL no change to pixel * 6 = CLR clear pixel to background * 7 = UND undefined SHRSETGCOL PHA LDY VDUPIXELS ; Pixels per byte CPY #$02 ; 2 is 320-mode (MODE 1) BNE :MODE0 AND #$80 BEQ :FORE320 PLA AND #$0F TAY LDA SHRCMASK320,Y ; Lookup mask in table >>> WRTMAIN STA SHRGFXBGMASK >>> WRTAUX RTS :FORE320 PLA AND #$0F TAY LDA SHRCMASK320,Y ; Lookup mask in table >>> WRTMAIN STA SHRGFXFGMASK STX SHRGFXACTION >>> WRTAUX RTS :MODE0 AND #$80 BEQ :FORE640 PLA AND #$03 TAY LDA SHRCMASK640,Y ; Lookup mask in table >>> WRTMAIN STA SHRGFXBGMASK >>> WRTAUX RTS :FORE640 PLA AND #$03 TAY LDA SHRCMASK640,Y ; Lookup mask in table >>> WRTMAIN STA SHRGFXFGMASK STX SHRGFXACTION >>> WRTAUX RTS * Wrapper to call SHRDEFPALM (which sets up default palette) SHRDEFPAL >>> XF2MAIN,SHRDEFPALM SHRDEFPALRET >>> ENTAUX RTS