*------------------------------- * * instrument.s * * This is the first part of what will hopefully become * my music compostion package. It is for creating * instruments, and experimenting with SID. Someday * some waveform analysis may appear but not today! * * Stephen L. Judd * 8/18/96 * * Standalone version, 9.15.96 * * Updated: 6/98 -- Displays instruments, updated load/save, * No longer copies shadow to SID -- only * changes affect SID * * ORG $0801 DSK '@0:insted' REL PUT 'playvars.i.s' PUT 'diskio.ext.s' MUSICED EXT MACMAN EXT * * Constants * CLEAR = 147 ;Clear screen HOME = 19 RVOF = 146 ;Reverse off UP = 145 DN = 17 LEFT = 157 RIGHT = 29 LGRN = 153 WHITE = 5 SID = $D400 ATK EQU 64 ;Codes to tell which function I DKY EQU 65 ;am performing. 0-31 for SID SUS EQU 66 RLS EQU 67 TRI EQU 68 SAW EQU 69 PUL EQU 70 NOI EQU 71 WID EQU 72 ;pulse width FRQ EQU 73 GAT EQU 74 SYN EQU 75 RNG EQU 76 TST EQU 77 FIL1 EQU 78 ;Filter on FIL2 EQU 79 FIL3 EQU 80 FLO EQU 81 FBP EQU 82 ;Bandpass FHI EQU 83 RES EQU 84 ;Resonance CUT EQU 85 ;Cutoff freq ILOAD EQU $FA ISAVE EQU $FB MUSED EQU $FC MACED EQU $FD * * Variables * POINT EQU $FE ;A pointer to use TEMP2 EQU $FC TEMP1 EQU $FB JOB EQU $FA ;Attack, decay, etc. FAQ1 EQU $61 ;Used by conversion routines *VOICE EQU COFFSET ;Current voice selected VOICE DFB 00 * * Kernal * CHROUT EQU $FFD2 PLOT EQU $FFF0 KGETIN EQU $FFE4 *------------------------------- * Some useful macros GOTOXY MAC LDX #]1 LDY #]2 CLC JSR PLOT <<< SETXY MAC ;Set POINT to point to a row,col LDA #<]1*40+1024+]2 STA POINT LDA #>]1*40+1024+]2 STA POINT+1 <<< *------------------------------- * * Basic header DO 0 DA $0800 ;Sneaky line link DA 6581 DFB $9E TXT '2073 slj 9/15/96' DFB 00,00,00 FIN *------------------------------- * * Init stuff * INIT INSTED ENT LDX #24 :L1 LDA SHADOW,X STA SID,X DEX BPL :L1 LDA SHADOW+24 ;Volume ORA #15 STA SHADOW+24 STA SID+24 LDA #128 STA 650 ;All keys repeat LDA #ATK STA JOB ;Start on Attack LDA #00 STA $D020 LDA #6 STA $D021 INIT2 LDA #147 JSR CHROUT LDA #142 ;Upper case JSR CHROUT JMP SETUP STEXT DFB HOME,RVOF,DN,DN,DN,DN,DN,DN,DN,DN,DN,DN DFB LGRN TXT 'attack :' DFB WHITE TXT '00 ' DFB LGRN TXT 'waveform:' DFB 13 TXT 'decay :' DFB WHITE TXT '00 tri saw pul noi' DFB 13,LGRN TXT 'sustain:' DFB WHITE TXT '00 ' DFB LGRN TXT 'pulse width:' DFB WHITE TXT ' 0' DFB 13,LGRN TXT 'release:' DFB WHITE TXT '00 ' DFB LGRN TXT 'freq:' DFB WHITE TXT ' 0' DFB 13,DN TXT ' gate ring' DFB 13 TXT ' sync test' DFB 13,DN,LGRN TXT 'filter:' DFB WHITE TXT ' v1 v2 v3' DFB 13 TXT ' low pass' DFB 13 TXT ' band pass' DFB 13 TXT ' high pass' DFB 13,DN,LGRN TXT 'resonance:' DFB WHITE TXT '00' DFB 13,LGRN TXT 'cutoff:' DFB WHITE TXT '0000' DFB HOME,RVOF,WHITE TXT ' v1 v2 v3 hi ' DFB 98 ;vertical bar DFB HOME,DN,DN,DN,DN,DN,DN,DN,DN,WHITE DFB 99,99,99,99,99,99,99,99 ;horiz bar TXT 'sid' DFB 99,99,99,99,99,99,99,99,107 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB UP,LEFT,98 DFB 00 SETUP LDA #>STEXT ;Now set up screen STA POINT+1 LDA #1024 STA POINT+1 :LOOP LDY #00 CLC LDA POINT ADC #40 STA POINT BCC :CONT INC POINT+1 :CONT TXA JSR PRINTLOW ;Only print the lower nibble INY LDA SHADOW,X * STA SID,X JSR PRINTHEX INY ;Second column TXA CLC ADC #7 JSR PRINTLOW INY LDA SHADOW+7,X * STA SID+7,X JSR PRINTHEX INY ;Third col TXA CLC ADC #14 JSR PRINTLOW INY LDA SHADOW+14,X * STA SID+14,X JSR PRINTHEX INY CPX #4 ;Past row 4 yet? BCS :SKIP ;Only 24 regs to print TXA CLC ADC #21 JSR PRINTLOW INY LDA SHADOW+21,X * STA SID+21,X JSR PRINTHEX :SKIP CPX #05 BNE :SKIP2 LDA #11 JSR PRINTLOW INY LDA SID+27 ;read-only reg JSR PRINTHEX :SKIP2 CPX #06 BNE :NOPE LDA #12 JSR PRINTLOW INY LDA SID+28 JSR PRINTHEX :NOPE INX CPX #7 BNE :LOOP :DONE * * This guy tells us which voice we're on * and also lets you toggle the voice 3 output * VOICE123 LDA #>1024 STA POINT+1 LDA VOICE BNE :TRY7 LDA #01 :TRY7 CMP #07 BNE :TRY14 LDA #06 :TRY14 CMP #14 BNE :DUN LDA #11 :DUN STA POINT LDY #01 JSR HILIGHT LDY #01 LDA $CB CMP #56 ;1 -- select voice 1 BNE :V2 JSR LOLIGHT LDA #00 STA VOICE BEQ :DONE :V2 CMP #59 ;2 -- select voice 2 BNE :V3 JSR LOLIGHT LDA #07 STA VOICE BNE :DONE :V3 CMP #8 ;3 -- select voice 3 BNE :OUT3 JSR LOLIGHT LDA #14 STA VOICE :OUT3 CMP #49 ;* -- toggle v3 output BNE :DONE LDA SHADOW+$18 EOR #$80 STA SHADOW+$18 STA SID+$18 :DONE * * The strategy is: print out your value, and if it is * your turn to be serviced, highlight the entry and * deal with the input. * ATTACK >>> SETXY,10;0 LDY #8 LDX VOICE LDA SHADOW+5,X LSR LSR LSR LSR STA TEMP1 JSR PRINTDEC LDA JOB CMP #ATK BNE DECAY LDY #6 JSR GET1 ASL ASL ASL ASL STA TEMP1 LDX VOICE LDA SHADOW+5,X AND #$0F ORA TEMP1 STA SHADOW+5,X STA SID+5,X DECAY >>> SETXY,11;0 ;Assume X=VOICE LDY #8 LDA SHADOW+5,X AND #$0F STA TEMP1 JSR PRINTDEC LDA JOB CMP #DKY BNE SUSTAIN LDY #6 JSR GET1 STA TEMP1 LDX VOICE LDA SHADOW+5,X AND #$F0 ORA TEMP1 STA SHADOW+5,X STA SID+5,X SUSTAIN >>> SETXY,12;0 LDY #8 LDA SHADOW+6,X LSR LSR LSR LSR STA TEMP1 JSR PRINTDEC LDA JOB CMP #SUS BNE RELEASE LDY #6 JSR GET1 ASL ASL ASL ASL STA TEMP1 LDX VOICE LDA SHADOW+6,X AND #$0F ORA TEMP1 STA SHADOW+6,X STA SID+6,X RELEASE >>> SETXY,13;0 LDY #8 LDA SHADOW+6,X AND #$0F STA TEMP1 JSR PRINTDEC LDA JOB CMP #RLS BNE TRIANGLE LDY #6 JSR GET1 STA TEMP1 LDX VOICE LDA SHADOW+6,X AND #$F0 ORA TEMP1 STA SHADOW+6,X STA SID+6,X TRIANGLE >>> SETXY,11;12 LDA VOICE CLC ADC #4 ;Register 4 TAX LDA #%00010000 STA TEMP1 AND SHADOW,X BEQ :CONT LDA #81-32 :CONT CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #TRI BNE SAWTOOTH LDY #2 JSR TOGGLE SAWTOOTH >>> SETXY,11;16 LDA VOICE LDA #%00100000 STA TEMP1 AND SHADOW,X BEQ :CONT LDA #81-32 :CONT CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #SAW BNE PULSE LDY #2 JSR TOGGLE PULSE >>> SETXY,11;20 LDA #%01000000 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #PUL BNE NOISE LDY #2 LDA VOICE CLC ADC #4 TAX JSR TOGGLE NOISE >>> SETXY,11;24 LDA #%10000000 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #NOI BNE PWIDTH LDY #2 JSR TOGGLE PWIDTH >>> SETXY,12;12 LDX VOICE LDA SHADOW+2,X STA TEMP2 LDA SHADOW+3,X AND #$0F STA SHADOW+3,X STA TEMP1 LDY #12 JSR BIGDEC4 ;Only four positions LDA JOB CMP #WID BNE FREQ LDY #10 JSR HILIGHT JSR GETIN BEQ FREQ LDX VOICE CMP #'<' BNE :DIV2 ASL SHADOW+2,X ROL SHADOW+3,X :DIV2 CMP #'>' BNE :PLUS LSR SHADOW+3,X ROR SHADOW+2,X :PLUS CMP #'+' BNE :MINUS INC SHADOW+2,X BNE :DONE INC SHADOW+3,X :MINUS CMP #'-' BNE :BIGPLUS LDA SHADOW+2,X BNE :C1 DEC SHADOW+3,X :C1 DEC SHADOW+2,X JMP :DONE :BIGPLUS CMP #219 ;shift-plus BNE :BIGMIN INC SHADOW+3,X :BIGMIN CMP #221 ;shift-minus BNE :UP DEC SHADOW+3,X :UP LDY #10 CMP #UP BNE :DN JSR LOLIGHT DEC JOB BNE :DONE :DN CMP #DN BNE :DONE JSR LOLIGHT INC JOB :DONE LDA SHADOW+2,X STA SID+2,X LDA SHADOW+3,X STA SID+3,X FREQ >>> SETXY,13;12 LDX VOICE LDA SHADOW,X STA TEMP2 LDA SHADOW+1,X STA TEMP1 LDY #5 JSR BIGDEC LDA JOB CMP #FRQ BNE GATE LDY #3 JSR HILIGHT JSR GETIN BEQ GATE LDX VOICE CMP #'+' BNE :MINUS INC SHADOW,X BNE :DONE INC SHADOW+1,X :MINUS CMP #'-' BNE :BIGPLUS LDA SHADOW,X BNE :C1 DEC SHADOW+1,X :C1 DEC SHADOW,X JMP :DONE :BIGPLUS CMP #219 ;shift-plus BNE :BIGMIN INC SHADOW+1,X :BIGMIN CMP #221 ;shift-minus BNE :MUL2 DEC SHADOW+1,X :MUL2 CMP #'<' BNE :DIV2 ASL SHADOW,X ROL SHADOW+1,X :DIV2 CMP #'>' BNE :UP LSR SHADOW+1,X ROR SHADOW,X :UP LDY #3 CMP #UP BNE :DN JSR LOLIGHT DEC JOB BNE :DONE :DN CMP #DN BNE :DONE JSR LOLIGHT INC JOB :DONE LDA SHADOW,X STA SID,X LDA SHADOW+1,X STA SID+1,X GATE >>> SETXY,15;0 LDA #4 CLC ADC VOICE TAX LDA #%00000001 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #GAT BNE SYNC LDY #3 JSR TOGGLE SYNC >>> SETXY,16;0 LDA #4 CLC ADC VOICE TAX LDA #%00000010 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #SYN BNE RING LDY #3 JSR TOGGLE RING >>> SETXY,15;5 LDA #4 CLC ADC VOICE TAX LDA #%00000100 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #RNG BNE TEST LDY #3 JSR TOGGLE TEST >>> SETXY,16;5 LDA #4 CLC ADC VOICE TAX LDA #%00001000 STA TEMP1 AND SHADOW,X BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #TST BNE FILTER1 LDY #3 JSR TOGGLE FILTER1 >>> SETXY,18;7 LDX #23 LDA #%00000001 STA TEMP1 AND SHADOW+23 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FIL1 BNE FILTER2 LDY #1 JSR TOGGLE FILTER2 >>> SETXY,18;10 LDA #%00000010 STA TEMP1 AND SHADOW+23 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FIL2 BNE FILTER3 LDY #1 JSR TOGGLE FILTER3 >>> SETXY,18;13 LDA #%00000100 STA TEMP1 AND SHADOW+23 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FIL3 BNE FILTERLO LDY #1 JSR TOGGLE FILTERLO >>> SETXY,19;0 LDX #$18 LDA #%00010000 STA TEMP1 AND SHADOW+$18 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FLO BNE FILTERBP LDY #7 JSR TOGGLE FILTERBP >>> SETXY,20;0 LDA #%00100000 STA TEMP1 AND SHADOW+24 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FBP BNE FILTERHI LDY #8 JSR TOGGLE FILTERHI >>> SETXY,21;0 LDA #%01000000 STA TEMP1 AND SHADOW+24 BEQ :CONT1 LDA #81-32 :CONT1 CLC ADC #32 LDY #00 STA (POINT),Y LDA JOB CMP #FHI BNE RESON LDY #8 JSR TOGGLE RESON >>> SETXY,23;0 LDY #10 LDA SHADOW+$17 LSR LSR LSR LSR STA TEMP1 JSR PRINTDEC LDA JOB CMP #RES BNE CUTOFF LDY #8 JSR GET1 ASL ASL ASL ASL STA TEMP1 LDA SHADOW+$17 AND #$0F ORA TEMP1 STA SHADOW+$17 STA SID+$17 CUTOFF >>> SETXY,24;0 LDA #00 STA TEMP1 LDA SHADOW+$16 ASL ROL TEMP1 ASL ROL TEMP1 ASL ROL TEMP1 ORA SHADOW+$15 STA TEMP2 LDY #7 JSR BIGDEC4 ;Only four positions LDA JOB CMP #CUT BNE :JDONE LDY #6 JSR HILIGHT JSR GETIN LDX VOICE CMP #'<' BNE :DIV2 ASL SHADOW+$16 LDA SHADOW+$15 ASL STA SHADOW+$15 CMP #8 BCC :JDONE AND #$07 STA SHADOW+$15 INC SHADOW+$16 :JDONE JMP :DONE :DIV2 CMP #'>' BNE :PLUS LSR SHADOW+$16 LDA #00 ROL ROL ROL ROL ORA SHADOW+$15 LSR STA SHADOW+$15 BPL :JDONE :PLUS CMP #'+' BNE :MINUS LDA SHADOW+$15 CLC ADC #01 AND #$07 STA SHADOW+$15 BNE :DONE INC SHADOW+$16 JMP :DONE :MINUS CMP #'-' BNE :BIGPLUS LDX SHADOW+$15 BNE :C1 DEC SHADOW+$16 LDX #$08 :C1 DEX STX SHADOW+$15 JMP :DONE :BIGPLUS CMP #219 ;shift-plus BNE :BIGMIN INC SHADOW+$16 :BIGMIN CMP #221 ;shift-minus BNE :UP DEC SHADOW+$16 :UP LDY #10 CMP #UP BNE :DN JSR LOLIGHT DEC JOB BNE :DONE :DN CMP #DN BNE :DONE JSR LOLIGHT INC JOB :DONE LDA SHADOW+$15 STA SID+$15 LDA SHADOW+$16 STA SID+$16 LOOPDONE LDA JOB CMP #MUSED BNE :C1 LDA #0 STA $028A ;Disable key repeat JMP MUSICED :C1 CMP #MACED BNE :C2 LDA #0 STA $028A ;Disable key repeat JMP MACMAN :C2 CMP #ILOAD BNE :C3 JSR LOAD JMP :C4 :C3 CMP #ISAVE BNE :C4 JSR SAVE :C4 LDA JOB CMP #CUT+1 BCC :CONT LDA #ATK STA JOB :CONT CMP #ATK BCS :DUN LDA #CUT STA JOB :DUN JMP DISPSID * * Print out the instrument list * LASTINST DFB $FF ;Last instrument accessed PRINST LDA #10 ;Row STA TEMP2 LDX #00 ;Instrument :LOOP STX TEMP1 LDX TEMP2 LDY #30 CLC JSR PLOT LDA #5 ;White JSR CHROUT LDA #32 LDX TEMP1 ;Check for highlight CPX LASTINST BNE :C1 LDA #'*' :C1 JSR CHROUT LDA #153 ;light green JSR CHROUT TXA ;Convert to hex byte CMP #10 SED ADC #$30 CLD JSR CHROUT LDA #32 JSR CHROUT TXA ;Multiply by six ASL ADC TEMP1 ASL TAY LDX #6 :LOOP2 LDA INAMES,Y ;And print name JSR CHROUT INY DEX BNE :LOOP2 INC TEMP2 ;Next row LDX TEMP1 ;And go back around! INX CPX #$0E BNE :LOOP RTS * * LOAD -- Load an instrument * LOAD LDY #21 LDX #01 CLC JSR PLOT JSR STROUT DFB 05 TXT 'load inst? (0-d)',00 JSR GETINS BMI :DONE TAX ;Instrument number STA LASTINST JSR SETVOICE LDA CVOICE STA CURVOICE LDA VOICE STA COFFSET JSR LOADINST :DONE PLA PLA JMP INIT2 * * SAVE -- Save instrument * SAVE LDY #21 LDX #01 CLC JSR PLOT JSR STROUT DFB 05 TXT 'save inst? (0-d)',00 JSR GETINS BMI :DONE STA TEMP1 ;Mult by 9 STA LASTINST ASL ASL ASL ADC TEMP1 TAX JSR SETVOICE LDY VOICE LDA SHADOW+2,Y STA INSTAB,X LDA SHADOW+3,Y STA INSTAB+1,X LDA SHADOW+4,Y ORA #$01 ;Set gate STA INSTAB+2,X LDA SHADOW+5,Y STA INSTAB+3,X LDA SHADOW+6,Y STA INSTAB+4,X LDA SHADOW+$16 STA INSTAB+6,X LDA SHADOW+$15 STA INSTAB+5,X LDY CVOICE LDA :BIT,Y AND SHADOW+$17 ;Check if filter is on BEQ :FILT LDA SHADOW+$17 AND #$F0 STA INSTAB+7,X LDA SHADOW+$18 AND #$F0 :FILT STA INSTAB+8,X ;0 means no filter JSR GETNAME :DONE PLA PLA JMP INIT2 :BIT DFB 0,1,2,4 * * GETINS -- Turn on cursor, read key. On exit, * .A contains the instrument # (or $FF if * invalid input entered, in which case N * is set). * BLNSW = $CC BLNCT = $CD BLNON = $CF GETINS LDA #$FF STA JOB LDX #1 JSR INPUT LDA STRBUF SEC SBC #48 CMP #10 BCC :DONE SBC #7 CMP #14 BCC :DONE LDA #$FF :DONE AND #$FF RTS * * Read in instrument name. TEMP1 must contain * instrument number. * GETNAME LDY #21 LDX #02 CLC JSR PLOT JSR STROUT TXT 'name? ',00 LDX #6 JSR INPUT LDA TEMP1 ASL ADC TEMP1 ASL ;times 6 TAX LDY #00 :LOOP1 LDA STRBUF,Y BEQ :LOOP2 STA INAMES,X INX INY BNE :LOOP1 :LOOP2 TYA ;CR accepts current name BEQ :DONE CPY #6 BCS :DONE LDA #32 STA INAMES,X INX INY BNE :LOOP2 :DONE RTS * * SETVOICE -- Deduce current voice from COFFSET * CVOICE DFB 00 SETVOICE LDA VOICE ;0, 7, or 14 BEQ :DONE SEC SBC #12 BCS :DONE LDA #1 :DONE CLC ADC #1 STA CVOICE ;Cvoice = 1, 2, or 3 RTS * * Kludged-in routine to check for F1 etc. * TEMPX DFB 00 GETIN STX TEMPX JSR KGETIN PHA LDX #07 :LOOP CMP :KEYTAB,X BNE :C1 LDY NUMLIGHT JSR LOLIGHT LDA :JOBTAB,X STA JOB BNE :DONE :C1 CMP :CREG,X BEQ :CONT DEX BPL :LOOP BMI :DONE :CONT LDA BITP,X LDX VOICE EOR SHADOW+4,X STA SHADOW+4,X STA SID+4,X :DONE LDX TEMPX PLA RTS :KEYTAB DFB 133,135,204,211 TXT 'af' DFB 198 ;shift-f :JOBTAB DFB MUSED,MACED,ILOAD,ISAVE DFB ATK,FRQ,FLO :CREG TXT 'gyretspn' BITP DFB 1,2,4,8,16,32,64,128 * * GET1 is a subroutine for inputting data for the "small" * registers, such as attack, etc. It expects POINT * to be set up for hilight/lolight etc. and returns * the new value of TEMP1 in A * Note that it clobbers temp2 * GET1 STY TEMP2 JSR HILIGHT JSR GETIN BEQ :DUN LDY TEMP2 CMP #'+' BNE :MINUS INC TEMP1 :MINUS CMP #'-' BNE :UP DEC TEMP1 :UP CMP #UP BNE :DN JSR LOLIGHT DEC JOB BPL :DUN :DN CMP #DN BNE :SID JSR LOLIGHT INC JOB ******************************** :SID DO 0 :SID CMP #'_' ;Toggle between SID registers BNE :DONE LDA JOB EOR #64 STA JOB :DONE LDA JOB CMP #ATK-1 ;Wrap around BNE :OK LDA #VOI STA JOB :OK CMP #VOL+1 BNE :OK2 LDA #ATK STA JOB :OK2 CMP #$FF ;Maybe we are in SID regs BNE :OK3 LDA #23 STA JOB :OK3 CMP #24 BNE :DUN LDA #00 STA JOB ******************************** FIN :DUN LDA TEMP1 AND #$0F RTS * * TOGGLE is for handling toggle-items, similar to GET1 above * Set up: POINT, Y, TEMP1=mask, and X=index into SID regs * TOGGLE INC POINT ;Starts pointing at dot STY TEMP2 JSR HILIGHT TXA PHA JSR GETIN TAY PLA TAX TYA LDY TEMP2 CMP #' ' BNE :UP LDA SHADOW,X EOR TEMP1 STA SHADOW,X STA SID,X RTS :UP CMP #UP BNE :DN JSR LOLIGHT DEC JOB :DN CMP #DN BNE :DONE JSR LOLIGHT INC JOB :DONE RTS * * HILIGHT will highlight some text on the screen. It * assumes POINT has been set to the appropriate screen * location and that Y contains the number of characters * to reverse from that location. * NUMLIGHT DFB 00 ;This part is a pretty kludge ;for GETIN HILIGHT STY NUMLIGHT :LOOP LDA (POINT),Y ORA #$80 STA (POINT),Y DEY BPL :LOOP RTS * * LOLIGHT on the other hand puts text back to normal * LOLIGHT :LOOP LDA (POINT),Y AND #$7F STA (POINT),Y DEY BPL :LOOP RTS * * PRINTHEX converts the byte in A to hex and prints it out. * * Stolen and adapted from Merlin 64 demo code somewhere * Sort-of. * * It expects (POINT),Y to point to the appropriate screen * location, and advances Y at each character. * PRINTHEX PHA LSR LSR LSR LSR JSR PRNIB PLA PRINTLOW AND #$0F ;Print low nibble PRNIB ORA #48 CMP #58 BCC PRIT SBC #57 PRIT STA (POINT),Y INY RTS * * printdec will print a small number to the screen in * decimal format. By small I really mean <20 * PRINTDEC PHA CMP #10 LDA #48 ADC #00 ;C set if 10 or greater STA (POINT),Y INY ROR ;Low bit set? PLA BCC :CONT SBC #10 CLC :CONT ADC #48 STA (POINT),Y INY RTS * * BIGDEC takes the number in TEMP1/TEMP2 and prints it out to * the screen over five bytes. * * Pretty slow and inefficient, yup! * BIGDEC LDX #48 ;X will count tens LDA TEMP2 SEC :LOOP SBC #<10000 PHA LDA TEMP1 SBC #>10000 BCC :C1 INX STA TEMP1 :C1 PLA BCC :C2 STA TEMP2 :C2 BCS :LOOP TXA STA (POINT),Y INY BIGDEC4 ;Enter here to only print 4 places LDX #48 LDA TEMP2 SEC :LOOP SBC #<1000 PHA LDA TEMP1 SBC #>1000 BCC :C1 INX STA TEMP1 :C1 PLA BCC :C2 STA TEMP2 :C2 BCS :LOOP TXA STA (POINT),Y INY BDEC3 LDX #47 LDA TEMP2 :SLOOP SEC :LOOP STA TEMP2 SBC #100 INX BCS :LOOP DEC TEMP1 BPL :SLOOP :DONE TXA STA (POINT),Y INY BDEC2 LDX #47 LDA TEMP2 SEC :LOOP STA TEMP2 SBC #10 INX BCS :LOOP TXA STA (POINT),Y INY LDA TEMP2 CLC ADC #48 STA (POINT),Y INY RTS