Mercurial > hg > Members > kono > nitros9-code
view level1/modules/kbvdio.asm @ 1514:b7d6cb1df834
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| author | boisy |
|---|---|
| date | Tue, 20 Jan 2004 02:43:23 +0000 |
| parents | f3557a63b11c |
| children | 7bdc60c48533 |
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******************************************************************** * KBVDIO - keyboard/video driver * * $Id$ * * Edt/Rev YYYY/MM/DD Modified by * Comment * ------------------------------------------------------------------ * ????/??/?? * Original Dragon Data distribution version * * 2004/01/04 Rodney Hamilton * Recoded anonymous fcb arrays, added some comments nam KBVDIO ttl keyboard/video driver * Disassembled 02/04/21 22:37:57 by Disasm v1.6 (C) 1988 by RML ifp1 use defsfile endc tylg set Drivr+Objct atrv set ReEnt+rev rev set $00 edition set 4 mod eom,name,tylg,atrv,start,size u0000 rmb 2 u0002 rmb 1 u0003 rmb 1 u0004 rmb 1 u0005 rmb 4 u0009 rmb 2 u000B rmb 1 u000C rmb 1 u000D rmb 11 u0018 rmb 1 u0019 rmb 1 u001A rmb 1 u001B rmb 1 u001C rmb 1 u001D rmb 2 u001F rmb 2 u0021 rmb 1 u0022 rmb 1 u0023 rmb 1 u0024 rmb 1 u0025 rmb 1 u0026 rmb 2 u0028 rmb 1 u0029 rmb 2 u002B rmb 1 u002C rmb 1 u002D rmb 2 u002F rmb 1 u0030 rmb 1 u0031 rmb 2 u0033 rmb 1 u0034 rmb 1 u0035 rmb 1 u0036 rmb 1 u0037 rmb 1 u0038 rmb 1 u0039 rmb 1 u003A rmb 1 vhwaddr rmb 2 address of keyboard hardware u003D rmb 1 SHIFTLOCK toggle u003E rmb 1 u003F rmb 1 u0040 rmb 1 u0041 rmb 1 u0042 rmb 1 u0043 rmb 1 u0044 rmb 1 u0045 rmb 1 SHIFT key flag u0046 rmb 1 CONTROL key flag u0047 rmb 1 u0048 rmb 1 u0049 rmb 1 u004A rmb 1 u004B rmb 10 u0055 rmb 26 u006F rmb 91 size equ . fcb $07 name fcs /KBVDIO/ fcb edition start lbra Init lbra Read lbra Write lbra GetStat lbra SetStat lbra Term Init lbsr AllocMem allocate video memory lbra L002D unsure why this is here.. timing? L002D pshs cc save CC orcc #IRQMask mask IRQs stu >D.KbdSta save our static mem ldd >D.IRQ get current IRQ vector address std >D.AltIRQ store in Alt. IRQ vector leax >OurIRQ,pcr point to our IRQ address stx >D.IRQ store in D.IRQ ldx #$FF00 get address of PIA stx <vhwaddr,u store in statics for IRQ routine clra clrb std <u0048,u sta $01,x clear $FF01 sta ,x clear $FF00 sta $03,x clear $FF03 comb B = $FF now stb <u003D,u stb $02,x put $FF in $FF02 stb <u003F,u stb <u0040,u stb <u0041,u lda #$34 sta $01,x put $34 in $FF01 lda #$3F sta $03,x put $3F in $FF03 lda $02,x get byte at $FF02 puls pc,cc get CC and return ldb #E$Write orcc #Carry set carry rts and return GetStat cmpa #SS.Ready SS.Ready call? bne L0082 branch if not lda <u0049,u suba <u0048,u bne GSOk ldb #E$NotRdy bra L009A L0082 cmpa #SS.EOF End of file? beq GSOk branch if so cmpa #SS.DStat lbeq L04E4 cmpa #SS.Joy joystick value acquisition? lbeq L085F cmpa #SS.AlfaS Alfa display status? lbeq L04CD branch if so SetStat ldb #E$UnkSvc L009A orcc #Carry rts Term pshs cc save CC orcc #IRQMask mask IRQs ldx >D.AltIRQ get Alt. IRQ address stx >D.IRQ and restore it to D.IRQ puls pc,cc get CC and return L00A9 incb cmpb #$7F bls L00AF GSOk clrb L00AF rts * Driver's IRQ Routine OurIRQ ldu >D.KbdSta get pointer to driver's statics ldx <vhwaddr,u get keyboard hardware address lda $03,x get byte bmi L00BE branch if hi bit set jmp [>D.SvcIRQ] else jump on L00BE lda $02,x lda #$FF sta $02,x lda ,x coma anda #$03 bne L00D4 clr $02,x lda ,x coma anda #$7F bne L00F1 L00D4 clra coma sta <u003F,u sta <u0040,u sta <u0041,u L00DF lda >D.DskTmr beq L00ED deca sta >D.DskTmr bne L00ED sta >$FF48 L00ED jmp [>D.AltIRQ] L00F1 bsr L013F bmi L00DF sta <u0047,u cmpa #$1F control-zero? bne L0101 com <u003D,u yes, toggle SHIFTLOCK bra L00DF L0101 ldb <u0048,u leax <u004A,u abx bsr L00A9 cmpb <u0049,u beq L0112 stb <u0048,u L0112 sta ,x beq L0132 cmpa u000D,u bne L0122 ldx u0009,u beq L0132 sta $08,x bra L0132 L0122 ldb #$03 cmpa u000B,u beq L012E ldb #$02 cmpa u000C,u bne L0132 L012E lda u0003,u bra L0136 L0132 ldb #S$Wake lda V.WAKE,u L0136 beq L013B os9 F$Send send signal to process L013B clr V.WAKE,u bra L00DF L013F clra sta <u003E,u sta <u0045,u sta <u0046,u coma sta <u0042,u sta <u0043,u sta <u0044,u deca sta $02,x strobe column #0 ($FF02) L0156 lda ,x read row register ($FF00) coma flip bits to active-high anda #$7F mask off joystick row beq L0169 no keypress in this column ldb #$FF L015F incb lsra bcc L0165 no key in this row, move along bsr L01AF keypress detected, process row & col L0165 cmpb #$06 final row checked? bcs L015F L0169 inc <u003E,u bump column counter orcc #Carry rol $02,x strobe next column bcs L0156 lbsr L01F8 bmi L01AE suba #$1B bcc L0191 not an alpha key adda #$1B ldb <u0046,u control key pressed? bne L0190 yes, return CTRL code adda #$40 no, convert to ASCII ldb <u0045,u shift key pressed? eorb <u003D,u andb #$01 bne L0190 adda #$20 L0190 rts L0191 ldb #3 three values per key mul lda <u0045,u shift key pressed? beq L019C incb yes, use 2nd value bra L01A3 L019C lda <u0046,u control key pressed? beq L01A3 addb #$02 yes, use 3rd value L01A3 pshs x leax >L023E,pcr clra lda d,x puls x L01AE rts * convert row number in B.reg from DRAGON to COCO order L01AF pshs b cmpb #$06 beq L01BF cmpb #$01 bhi L01BD addb #$04 bra L01BF L01BD subb #$02 L01BF lslb multiply row * 8 lslb lslb addb <u003E,u add column. B.reg now = keycode ($00-$37) cmpb #$31 is this the CLEAR key? bne L01CE inc <u0046,u yes, set control pressed flag puls pc,b L01CE cmpb #$37 is this a SHIFT key? bne L01D7 com <u0045,u yes, set shift pressed flag puls pc,b L01D7 pshs x leax <u0042,u bsr L01E2 puls x puls pc,b L01E2 pshs a lda ,x bpl L01EC stb ,x puls pc,a L01EC lda $01,x bpl L01F4 stb $01,x puls pc,a L01F4 stb $02,x puls pc,a L01F8 pshs y,x,b leax <u003F,u ldb #$03 pshs b L0201 leay <u0042,u ldb #$03 lda ,x bmi L021D L020A cmpa ,y bne L0214 clr ,y com ,y bra L021D L0214 leay $01,y decb bne L020A lda #$FF sta ,x L021D leax $01,x dec ,s bne L0201 leas $01,s leax <u0042,u lda #$03 L022A ldb ,x+ bpl L0235 deca bne L022A orcc #Negative puls pc,y,x,b L0235 leax <u003F,u bsr L01E2 tfr b,a puls pc,y,x,b *RVH: the following is a non-alpha key lookup table with *normal/shift/control codes for each key (1D,1E,7F missing) L023E fcb $0C,$1C,$13 UP-ARROW (FF| FS|DC3) L0241 fcb $0A,$1A,$12 DN-ARROW (LF|SUB|DC2) L0244 fcb $08,$18,$10 LF-ARROW (BS|CAN|DLE) L0247 fcb $09,$19,$11 RT-ARROW (HT| EM|DC1) L024A fcb $20,$20,$20 SPACEBAR L024D fcb $30,$30,$1F 0 0 . (1F=shiftlock toggle) L0250 fcb $31,$21,$7C 1 ! | L0253 fcb $32,$22,$00 2 " null L0256 fcb $33,$23,$7E 3 # ~ L0259 fcb $34,$24,$00 4 $ null L025C fcb $35,$25,$00 5 % null L025F fcb $36,$26,$00 6 & null L0262 fcb $37,$27,$5E 7 ' ^ L0265 fcb $38,$28,$5B 8 ( [ L0268 fcb $39,$29,$5D 9 ) ] L026B fcb $3A,$2A,$00 : * null L026E fcb $3B,$2B,$00 ; + null L0271 fcb $2C,$3C,$7B , < { L0274 fcb $2D,$3D,$5F - = _ L0277 fcb $2E,$3E,$7D . > } L027A fcb $2F,$3F,$5C / ? \ L027D fcb $0D,$0D,$0D ENTER L0280 fcb $00,$00,$00 CLEAR? L0283 fcb $05,$03,$1B BREAK (ENQ|ETX|ESC) Read leax <u004A,u ldb <u0049,u orcc #IRQMask cmpb <u0048,u beq L029F abx lda ,x lbsr L00A9 stb <u0049,u andcc #^(IRQMask+Carry) rts L029F lda V.BUSY,u sta V.WAKE,u andcc #^IRQMask ldx #$0000 os9 F$Sleep clr V.WAKE,u ldx <u004B L02AF ldb <$36,x beq Read cmpb #$04 L02B6 bcc Read coma rts * Allocate video memory on a 512 byte boundary AllocMem pshs y,x clr <u0025,u clr <u002C,u L02C2 pshs u save static mem pointer ldd #768 L02C7 os9 F$SRqMem get 768 bytes tfr u,d put pointer into D tfr u,x and X bita #$01 odd or even page? beq L02D8 branch if even leax >256,x else memory not on 512 byte boundary L02D6 bra L02DC L02D8 leau >512,u free last page L02DC ldd #256 get page amount os9 F$SRtMem and return page to system puls u get static mem pointer stx <u001D,u save pointer to page clra clrb bsr L0303 stx <u0021,u leax >512,x stx <u001F,u lbsr L0459 clear screen lda #$60 sta <u0023,u sta <u002B,u clrb puls pc,y,x L0303 pshs x,a lda >$FF22 anda #$07 ora ,s+ sta >$FF22 tstb bne L0320 stb >$FFC0 stb >$FFC2 stb >$FFC4 lda <u001D,u bra L032C L0320 stb >$FFC0 stb >$FFC3 stb >$FFC5 lda <u002D,u L032C ldb #$07 ldx #$FFC6 lsra L0332 lsra bcs L033B sta ,x+ leax $01,x bra L033F L033B leax $01,x sta ,x+ L033F decb bne L0332 clrb puls pc,x Write ldb <u0025,u bne L0387 tsta bmi L0371 cmpa #$1F bls L03BC cmpa #$7C bne L0359 lda #$61 bra L0371 L0359 cmpa #$7E bne L0361 lda #$6D bra L0371 L0361 cmpa #$60 bcs L036B suba #$20 ora #$40 bra L0371 L036B cmpa #$40 bcs L0371 suba #$40 L0371 ldx <u0021,u eora #$40 sta ,x+ stx <u0021,u cmpx <u001F,u bcs L0382 bsr L039C L0382 lbsr L0415 clrb rts L0387 cmpb #$01 beq L0394 clr <u0025,u sta <u0029,u jmp [<u0026,u] L0394 sta <u0028,u inc <u0025,u * no operation entry point L039A clrb rts L039C ldx <u001D,u leax <$20,x L03A2 ldd ,x++ std <-$22,x cmpx <u001F,u bcs L03A2 leax <-$20,x stx <u0021,u lda #$20 ldb #$60 L03B6 stb ,x+ deca bne L03B6 L03BB rts L03BC cmpa #27 bcc L03BB cmpa #$10 bcs L03CE ldb <u002C,u bne L03CE ldb #E$NotRdy orcc #Carry rts L03CE leax <L03D6,pcr lsla ldd a,x jmp d,x * dispatch table for display function codes L03D6 fdb L039A-L03D6 $FFC4 00: no-op fdb L0467-L03D6 $0091 01: home cursor fdb L047B-L03D6 $00A5 02: cursor xy fdb L04A6-L03D6 $00D0 03: erase line fdb L039A-L03D6 $FFC4 04: no-op fdb L039A-L03D6 $FFC4 05: no-op fdb L044B-L03D6 $0075 06: cursor right fdb L039A-L03D6 $FFC4 07: no-op fdb L043D-L03D6 $0067 08: cursor left fdb L04B8-L03D6 $00E2 09: cursor up fdb L0424-L03D6 $004E 0A: cursor down fdb L039A-L03D6 $FFC4 0B: no-op fdb L0459-L03D6 $0083 0C: clear screen fdb L040C-L03D6 $0036 0D: return cursor to start of line fdb L04C8-L03D6 $00F2 0E: display alpha fdb L0520-L03D6 $014A 0F: display graphics fdb L0604-L03D6 $022E 10: preset screen to specific color fdb L05DF-L03D6 $0209 11: set color fdb L05F3-L03D6 $021D 12: end graphics fdb L0624-L03D6 $024E 13: erase graphics fdb L062F-L03D6 $0259 14: home graphics cursor fdb L0648-L03D6 $0272 15: Set Graphics Cursor fdb L06B5-L03D6 $02DF 16: Draw Line fdb L06B0-L03D6 $02DA 17: Erase Line fdb L065F-L03D6 $0289 18: Set Point fdb L065A-L03D6 $0284 19: Erase Point fdb L077E-L03D6 $03A8 1A: Draw Circle * $0D - return cursor to start of line (carriage return) L040C bsr L0472 tfr x,d andb #$E0 stb <u0022,u L0415 ldx <u0021,u lda ,x sta <u0023,u lda #$20 sta ,x andcc #^Carry rts * $0A - cursor down L0424 bsr L0472 leax <$20,x cmpx <u001F,u bcs L0438 leax <-$20,x pshs x lbsr L039C puls x L0438 stx <u0021,u bra L0415 * $08 - cursor left L043D bsr L0472 cmpx <u001D,u bls L0449 leax -$01,x stx <u0021,u L0449 bra L0415 * $06 - cursor right L044B bsr L0472 leax $01,x cmpx <u001F,u bcc L0457 stx <u0021,u L0457 bra L0415 * $0C - clear screen L0459 bsr L0467 lda #$60 L045D sta ,x+ cmpx <u001F,u bcs L045D lbra L0415 * $01 - home cursor L0467 bsr L0472 ldx <u001D,u stx <u0021,u lbra L0415 L0472 ldx <u0021,u lda <u0023,u sta ,x rts * $02 XX YY - cursor xy (move cursor to XX-32,YY-32) L047B leax <L0481,pcr lbra L064B L0481 bsr L0472 ldb <u0029,u subb #$20 lda #$20 mul addb <u0028,u adca #$00 subd #$0020 addd <u001D,u cmpd <u001F,u bcc L04A3 std <u0021,u lbsr L0415 clrb L04A3 lbra L0415 * $03 - erase line L04A6 lbsr L040C do a CR ldb #$20 32 chars per line lda #$60 space char for VDG screen ldx <u0021,u L04B0 sta ,x+ fill screen line with 'space' decb bne L04B0 lbra L0415 * $09 - cursor up L04B8 bsr L0472 leax <-$20,x cmpx <u001D,u bcs L04C5 stx <u0021,u L04C5 lbra L0415 * $0E - display alpha L04C8 clra clrb lbra L0303 L04CD ldx $06,y ldd <u001D,u std $04,x ldd <u0021,u std $06,x ldb <u003D,u stb $01,x clrb rts * 4-color mode color table L04E0 fcb $00,$55,$AA,$FF L04E4 lda <u002C,u bne L04EE L04E9 ldb #E$NotRdy orcc #Carry rts L04EE ldd <u0034,u lbsr L0684 tfr a,b andb ,x L04F8 bita #$01 bne L0507 lsra lsrb tst <u0024,u bmi L04F8 lsra lsrb bra L04F8 L0507 pshs b ldb <u003A,u andb #$FC L050E orb ,s+ ldx $06,y stb $01,x ldd <u0034,u std $06,x ldd <u002D,u std $04,x clrb rts * $0F - display graphics L0520 leax <L0526,pcr lbra L064B L0526 ldb <u002C,u bne L0566 pshs u ldd #$1900 os9 F$SRqMem tfr u,d puls u bcs L0585 tfr a,b bita #$01 beq L0543 adda #$01 bra L0545 L0543 addb #$18 L0545 pshs u,a tfr b,a clrb tfr d,u ldd #$0100 os9 F$SRtMem puls u,a bcs L0585 clrb std <u002D,u addd #$1800 std <u002F,u inc <u002C,u lbsr L0624 L0566 lda <u0029,u sta <u003A,u anda #$03 leax >L04E0,pcr lda a,x sta <u0036,u sta <u0037,u lda <u0028,u cmpa #$01 bls L0586 ldb #E$BMode illegal mode orcc #Carry L0585 rts L0586 tsta beq L05A6 ldd #$C003 std <u0038,u lda #$01 sta <u0024,u lda #$E0 ldb <u0029,u andb #$08 beq L059F lda #$F0 L059F ldb #$03 leax <L05D3,pcr bra L05BE L05A6 ldd #$8001 std <u0038,u lda #$FF sta <u0036,u sta <u0037,u sta <u0024,u lda #$F0 ldb #$07 leax <L05D7,pcr L05BE stb <u0033,u stx <u0031,u ldb <u0029,u andb #$04 lslb pshs b ora ,s+ ldb #$01 lbra L0303 * 4-color mode pixel masks L05D3 fcb $C0,$30,$0C,$03 * 2-color mode pixel masks L05D7 fcb $80,$40,$20,$10,$08,$04,$02,$01 * $11 - set color L05DF leax <L05E5,pcr lbra L0781 L05E5 clr <u0028,u lda <u0024,u bmi L05F0 inc <u0028,u L05F0 lbra L0566 * $12 - end graphics L05F3 pshs u ldu <u002D,u ldd #6144 size of graphics screen os9 F$SRtMem puls u clr <u002C,u rts * $10 - preset screen to specified color L0604 leax <L060A,pcr lbra L0781 L060A lda <u0029,u tst <u0024,u bpl L061A ldb #$FF anda #$01 beq L0624 bra L0625 L061A anda #$03 leax >L04E0,pcr ldb a,x bra L0625 * $13 - erase graphics L0624 clrb L0625 ldx <u002D,u L0628 stb ,x+ cmpx <u002F,u bcs L0628 * $14 - home graphics cursor L062F clra clrb std <u0034,u rts L0635 ldd <u0028,u cmpb #192 bcs L063E ldb #192-1 L063E tst <u0024,u bmi L0644 lsra L0644 std <u0028,u rts * $15 - set graphics cursor L0648 leax <L0653,pcr L064B stx <u0026,u inc <u0025,u clrb rts L0653 bsr L0635 std <u0034,u clrb rts * $19 - erase point L065A clr <u0036,u bra L065F * $18 - set point L065F leax <L0664,pcr bra L064B L0664 bsr L0635 std <u0034,u bsr L0673 lda <u0037,u sta <u0036,u clrb rts L0673 bsr L0684 tfr a,b comb andb ,x stb ,x anda <u0036,u ora ,x sta ,x rts L0684 pshs y,b,a ldb <u0024,u bpl L068C lsra L068C lsra lsra pshs a ldb #$BF subb $02,s lda #$20 mul addb ,s+ adca #$00 ldy <u002D,u leay d,y lda ,s sty ,s anda <u0033,u ldx <u0031,u lda a,x puls pc,y,x * $17 - erase line L06B0 clr <u0036,u bra L06B5 * $16 - draw line L06B5 leax <L06BA,pcr bra L064B L06BA lbsr L0635 leas -$0E,s std $0C,s bsr L0684 stx $02,s sta $01,s ldd <u0034,u bsr L0684 sta ,s clra clrb std $04,s lda #$BF suba <u0035,u sta <u0035,u lda #$BF suba <u0029,u sta <u0029,u lda #$FF sta $06,s clra ldb <u0034,u subb <u0028,u sbca #$00 bpl L06F7 nega negb sbca #$00 neg $06,s L06F7 std $08,s bne L0700 ldd #$FFFF std $04,s L0700 lda #$E0 sta $07,s clra ldb <u0035,u subb <u0029,u sbca #$00 bpl L0715 nega negb sbca #$00 neg $07,s L0715 std $0A,s bra L0721 L0719 sta ,s ldd $04,s subd $0A,s std $04,s L0721 lda ,s tfr a,b anda <u0036,u comb andb ,x pshs b ora ,s+ sta ,x cmpx $02,s bne L073B lda ,s cmpa $01,s beq L076F L073B ldd $04,s bpl L0749 addd $08,s std $04,s lda $07,s leax a,x bra L0721 L0749 lda ,s ldb $06,s bpl L075F lsla ldb <u0024,u bmi L0756 lsla L0756 bcc L0719 lda <u0039,u leax -$01,x bra L0719 L075F lsra ldb <u0024,u bmi L0766 lsra L0766 bcc L0719 lda <u0038,u leax $01,x bra L0719 L076F ldd $0C,s std <u0034,u leas $0E,s lda <u0037,u sta <u0036,u clrb rts * $1A - draw circle L077E leax <L0789,pcr L0781 stx <u0026,u com <u0025,u clrb rts L0789 leas -$04,s ldb <u0029,u get radius stb $01,s stack it clra sta ,s addb $01,s adca #$00 nega negb sbca #$00 addd #$0003 std $02,s L07A0 lda ,s cmpa $01,s bcc L07D2 ldb $01,s bsr L07E0 clra ldb $02,s bpl L07BA ldb ,s lslb rola lslb rola addd #$0006 bra L07CA L07BA dec $01,s clra ldb ,s subb $01,s sbca #$00 lslb rola lslb rola addd #$000A L07CA addd $02,s std $02,s inc ,s bra L07A0 L07D2 lda ,s cmpa $01,s bne L07DC ldb $01,s bsr L07E0 L07DC leas $04,s clrb rts L07E0 leas -$08,s sta ,s clra std $02,s nega negb sbca #$00 std $06,s ldb ,s clra std ,s nega negb sbca #$00 std $04,s ldx $06,s bsr L0829 ldd $04,s ldx $02,s bsr L0829 ldd ,s ldx $02,s bsr L0829 ldd ,s ldx $06,s bsr L0829 ldd $02,s ldx ,s bsr L0829 ldd $02,s ldx $04,s bsr L0829 ldd $06,s ldx $04,s bsr L0829 ldd $06,s ldx ,s bsr L0829 leas $08,s rts L0829 pshs b,a ldb <u0035,u clra leax d,x cmpx #$0000 bmi L083B cmpx #$00BF ble L083D L083B puls pc,b,a L083D ldb <u0034,u clra tst <u0024,u bmi L0848 lslb rola L0848 addd ,s++ tsta beq L084E rts L084E pshs b tfr x,d puls a tst <u0024,u lbmi L0673 lsra lbra L0673 L085F ldx $06,y pshs y,cc orcc #IRQMask lda #$FF clr >$FF02 ldb >$FF00 ldy $04,x bne L0878 andb #$01 bne L087C bra L087D L0878 andb #$02 beq L087D L087C clra L087D sta $01,x lda >$FF03 ora #$08 ldy $04,x bne L088B anda #$F7 L088B sta >$FF03 lda >$FF01 anda #$F7 bsr L08AA std $04,x lda >$FF01 ora #$08 bsr L08AA pshs b,a ldd #$003F subd ,s++ std $06,x clrb puls pc,y,cc L08AA sta >$FF01 clrb bsr L08BA bsr L08BA bsr L08BA bsr L08BA lsrb lsrb clra rts L08BA pshs b lda #$7F tfr a,b L08C0 lsrb cmpb #$03 bhi L08CC lsra lsra tfr a,b addb ,s+ rts L08CC addb #$02 andb #$FC pshs b anda #$FC sta >$FF20 tst >$FF00 bpl L08E0 adda ,s+ bra L08C0 L08E0 suba ,s+ bra L08C0 emod eom equ * end