Apple II Magazines (DO)

home *** CD-ROM | disk | FTP | other *** search

/ Apple II Magazines (DO) / Nibble Volume 07, No. 06 (1986-06)(MicroSPARC)(Side A).zip / Nibble Volume 07, No. 06 (1986-06)(MicroSPARC)(Side A).do / VORATIO.BIN.S < prev next >

Wrap

Text File | 1996-12-24 | 24KB | 763 lines

******************************** * VORATIO.BIN * * BY DARRELL FETZER * * COPYRIGHT 1986 * * BY MICROSPARC, INC. * * CONCORD, MA 01742 * * * * MERLIN ASSEMBLER * ******************************** LIFLOC = $6E8 LEVLOC = $6F2 SCLOC = $6D9 KEYSTR = $C000 KEYCLR = $C010 GRAPHIC = $C050 TEXT = $C051 MIXED = $C053 PAGE1 = $C054 HIRES = $C057 RANDOM = $EFAE ;APPLESOFT RANDOM # ROUTINE HOME = $FC58 WAIT = $FCA8 SLNGH = $6 DEPTH = $7 ADDLEN = $8 LENGTH = $9 GRBUFFL2 = $19 GRBUFFH2 = $1A PRINTL = $1B PRINTH = $1C HDPTR = $1E *** $1F = HIGH BYTE OF 16-POINTER RNDL = $9F RNDH = $A0 PITCH = $CE TIME = $CF R1 = $D6 *** $D7 = HIGH BYTE OF 16-COUNTER DELTAX = $EB DELTAY = $EC VECL = $ED VECH = $EE SHIFTER = $EF X = $F9 ;CURRENT X COORD OF HEAD Y = $FA ;CURRENT Y COORD. OF HEAD APCOUNT = $FB GRBUFFL = $FC GRBUFFH = $FD XI = $FE ;X COORD. OF MOVEMENT VECTOR YJ = $FF ;Y COORD. OF MOVEMENT VECTOR WORM = $6000 VECPTRL = $6065 VECPTRR = $6066 VECTBL = $6067 TABL1 = $60C7 LINE = $60D4 TBL4 = $60F5 TBL5 = $60F9 LCOUNT = $60FD SPEED = $60FE MX = $60FF SEGLOC = $6100 MUSH = $6200 APPLE = $6220 TBL1 = $624F TBL2 = $630F TBL3 = $63CF XOFF = $648F XBASE = $65A7 TABL2 = $66B8 TABL3 = $66C5 LEVEL1 = $66D2 TABLEL = $6984 TABLEH = $6997 ******************************** ORG $69AA *** DRAW BORDERS OF SCREEN AND *** PUT INFO ON BOTTOM PROG LDX #$00 ;START DRAW LDY #$00 ;FILLS HIRES SCREEN SOLID WHITE LDA TBL1,X STA GRBUFFL STA GRBUFFL2 LDA TBL2,X STA GRBUFFH LDA TBL3,X STA GRBUFFH2 LDA #$7F DRAW1 STA (GRBUFFL),Y STA (GRBUFFL2),Y INY CPY #$28 BCC DRAW1 INX CPX #$A3 BLT DRAW LDX #$00 LUP3 LDY #$00 ;PUTS SCORE INFO ON THE BOTTOM OF THE TXT SCREEN LDA TBL4,X STA PRINTL LDA TBL5,X STA PRINTH LUP1 LDA #$20 STA (PRINTL),Y INY CPY #$28 BNE LUP1 INX CPX #$04 BNE LUP3 JSR PSCRN ;CLEARS THE MIDDLE OF THE SCREEN BIT GRAPHIC BIT HIRES BIT PAGE1 BIT MIXED LDA #>SCLOC STA PRINTH LDA #<SCLOC-6 STA PRINTL LDX #$00 LDY #$00 LUP2 LDA LINE,X STA (PRINTL),Y INX INY CPY #$21 BLT LUP2 *** SETUP VARIABLES LDA #$FF ;SET INTERNAL LEVEL COUNT TO -1 STA LCOUNT LDA #>VECTBL STA VECH LDA #>SEGLOC STA HDPTR+1 STA R1+1 LDA #<SEGLOC STA R1 LDA #$F0 ;SET MINIMUM SPEED TO 240 STA MINSPD LDA #$00 ;SET # OF POINTS FOR EATING APPLE TO BASE VALUE STA POINT *** OUTSIDE LOOP. PROGRAM COMES *** HERE WHEN PLAYER MAKES NEW *** LEVEL. START1 INC LCOUNT ;ADVANCE TO NEXT LEVEL LDA LCOUNT LSR ;IF LEVEL IS ODD THEN POINTS PER APPLE INCREASES BCS NO ;OTHERWISE STAYS THE SAME INC POINT NO LDA #$00 ;SET DEATH ON LEVEL COUNTER TO 0 STA DIE? SEC ;INCREASE MINIMUM SPEED LDA MINSPD SBC #$05 STA SPEED ;SAVE IT STA MINSPD INC LEVLOC+1 ;UPDATE INFO ON THE TEXT SCREEN LDA LEVLOC+1 CMP #': BNE START LDA #'0 STA LEVLOC+1 INC LEVLOC LDA LEVLOC CMP #'2 ;IF PLAYER MAKES IT TO LEVEL 20 BNE START JMP EXIT ;RETURN TO BASIC *** INSIDE LOOP. PLAYER COMES *** HERE WHEN HE DIES. START JSR PSCRN ;CLEAR WRECKAGE FROM SCREEN JSR LEVELSET ;SET BARRICADES ON SCREEN LDA MINSPD ;SET PLAYERS CURRENT SPEED STA SPEED ;TO MINIMUM LDA #$03 ;SET DIRECTION VECTOR TO 3,0 STA XI LDA #$00 STA YJ LDA VECTBL ;SET LINKED LIST POINTERS TO CORRESPOND STA VECPTRL ;TO THE 3,0 INITIALIZATION LDA VECTBL+3 STA VECPTRR LDA #$0A ;SET THE # OF APPLES TO BE EATEN ON A LEVEL TO STA APCOUNT ;TEN LDA #$01 ;SET THE LENGTH OF THE WORM TO 1 STA LENGTH LDA #$09 ;SET THE # OF SEGMENTS TO BE ADDED TO 9 STA ADDLEN LDA #<SEGLOC ;SET THE HEAD POINTER TO THE TOP OF THE QUEUE STA HDPTR LDA #$15 ;SET INITIAL X COORD TO 15 LDY #$00 STA (HDPTR),Y ;SAVE ON QUEUE STA X ;AND IN CURRENT HEAD POSITION INY LDA #$94 ;SET INITIAL Y COORD TO 148 STA (HDPTR),Y ;SAVE ON QUEUE STA Y ;AND IN CURRENT HEAD POSITION JSR SEGSET ;DRAW THE HEAD JSR MSAFE ;DRAW A MUSHROOM IN A SAFE PLACE JSR SAFE ;DRAW AN APPLE IN A SAFE PLACE BIT KEYCLR ;CLEAR STROBE LDA KEYSTR ;WAIT FOR A KEY PRESS (K.P.) TO START GAME BPL *-3 *** ALL CONTROL OF WORM TAKES *** PLACE IN THIS LOOP WAIT1 LDA KEYSTR ;GET FIRST COMMAND BPL NOKEY ;NO COMMAND ACT IN CURRENT DIRECTION CMP #$9B ;ESCAPE BNE KEY1 ;NO, TEST NEXT KEY JMP EXIT ;EXIT TO BASIC KEY1 CMP #$A0 ;SPACE BNE KEY2 ;NO, GO TO NEXT TEST BIT KEYCLR ;CLEAR STROBE LDA KEYSTR ;WAIT FOR ANOTHER K.P. TO UNFREEZE GAME BPL *-3 ;NO KEY KEY2 CMP #"L ;WAS IT AN L BNE KEY3 ;NOPE BIT KEYCLR ;CLEAR STROBE JMP START1 ;JMP TO SET UP FOR NEXT LEVEL KEY3 JSR MOVMNT ;INTERPRET K.P. AS MOVEMENT COMMAND NOKEY BIT KEYCLR ;CLEAR STROBE JSR POSUPD ;UPDATE WORM'S POSITION LDA COLL ;LOAD COLLISION COUNTER BNE MOLIFE ;IF NONZERO COLLISION OCCURED LDA SPEED ;OTHERWISE GET CURR. SPEED JSR WAIT ;AND WAIT LDA APCOUNT ;GET # OF APPLES LEFT OF ORIG. TEN BNE NOTEN ;NONZERO # LEFT GO FOR MORE LDA DIE? ;DONE WITH LEVEL. DID PLAYER DIE ON LEVEL EVER BNE DIETEN ;NONZERO = YES AND NO BONUS LDY #$0A ;NO DEATH IS REWARDED WITH 1000 PT. BONUS MBONUS JSR SCORE1 ;ADD 100 TO SCORE DEY BNE MBONUS ;MORE SCORE TO GIVE IF NOT DONE WITH 1000 PTS DIETEN JMP START1 ;GO TO NEXT LEVEL NOTEN JMP WAIT1 ;GET ANOTHER K.P. *** START OF SUBROUTINES MOLIFE LDA #$20 ;SET UP FOR THE DEATH SOUND STA PITCH LDA #$00 STA EPITCH LDA #$03 STA TIME1 JSR SOUND LDX LIFLOC DEX ;DECREASE THE NUMBER OF LIVES THE PLAYER HAS CPX #'/ ;IS IT LESS THAN ZERO BEQ EXIT ;IF YES THAN THE GAME IS OVER STX LIFLOC ;OTHERWISE SAVE HIS CURRENT # OF LIVES ON SCRN. LDA KEYSTR ;WAIT FOR K.P. BPL *-3 INC DIE? ;INCREMENT DEATH ON LEVEL COUNTER (NO BONUS) JMP START ;ERASE SCREEN AND START LEVEL AGAIN EXIT BIT KEYCLR JSR HOME ;CLEAR TEXT SCREEN LDA TEXT ;TEXT DISPLAY RTS ;RETURN TO BASIC *** MOVEMENT ROUTINE INTERPRETS *** KEYSTROKE AND GETS THE PROPER *** VALUE FROM THE LINKED LIST MOVMNT CMP #"J ;IS K.P. A J BNE NEXT ;NO TRY ANOTHER TEST LDA VECPTRL ;J MEANS LEFT SO GET LEFT POINTER FOR LINKED LIST STA VECL ;AND SAVE IT LDY #$00 LDA (VECL),Y ;LOAD NEX LEFT POINTER FROM LINKED LIST STA VECPTRL ;SAVE IN LEFT POINTER INY LDA (VECL),Y ;GET X COORD OF DIRECTION VECTOR STA XI ;SAVE IN X COORD OF MOVEMENT VECTOR INY LDA (VECL),Y ;GET Y COORD. STA YJ ;AND SAVE INY LDA (VECL),Y ;GET NEW RIGHT POINTER FOR L.L. STA VECPTRR ;SAVE IT BCC OVER ;BRANCH ALWAYS BECAUSE K.P. WAS "J" NEXT CMP #"K BNE NEXT2 ;NOT A K TRY ANOTHER TEST LDA VECPTRR ;K IS RIGHT SO GET RIGHT POINTER FOR L.L. STA VECL ;SAVE FOR INDIRECT ADDRESSING LDY #$00 LDA (VECL),Y ;GET NEW LEFT L.L. POINTER STA VECPTRL INY LDA (VECL),Y ;GET X COORD STA XI INY LDA (VECL),Y ;Y COORD STA YJ INY LDA (VECL),Y ;NEW RIGHT POINTER STA VECPTRR BCC OVER ;BRANCH ALWAYS NEXT2 CMP #"F ;WAS K.P. AN F BNE NEXT3 ;TRY ANOTHER LDA SPEED ;GET CURRENT SPEED CMP #$10 ;IS IT AT A MAX. BLT OVER ;YES SO IGNORE COMMAND SEC SBC #$0A ;INCREASE SPEED BY TEN STA SPEED BCC OVER ;BRANCH ALWAYS NEXT3 CMP #"D ;IS K.P. A D BNE OVER ;NOPE SO K.P. WAS MEANINGLESS LDA SPEED ;GET CURRENT SPEED CMP MINSPD ;IS IT AT A MIN. BGE OVER ;YES, IGNORE COMMAND CLC ADC #$0A ;OTHERWISE DECREASE SPEED BY 10 STA SPEED OVER RTS ;GET OUT OF HERE *** POSITION UPDATE. UPDATES THE *** POSITION OF THE WORM IN *** ACCORD WITH DATA FROM MOVEMENT *** OR IF NO KEY WAS PRESSED, WORM *** CONTINUES WITH CURRENT PATH POSUPD LDA ADDLEN ;GET # OF SEGMENTS TO ADD TO BACK OF WORM CMP #$00 ;= 0 SO GOTO QUEUE UPDATE BEQ EQUAL BGE GREATER ;>0 SO ADD SEGMENTS TO BACK EQUAL LDY #$00 LDA (R1),Y ;GET TOP VALUE FROM QUEUE STA X ;SAVE FOR ERASE SUBROUTINE INY LDA (R1),Y ;GET NEXT VALUE STA Y JSR SEGCLR ;CLEAR SEGMENT FROM THE BACK OF THE WORM LDY #$00 LDX LENGTH ;GET CURRENT LENGTH DEX ;AND DECREASE BY TWO SINCE A SEGMENT WAS ERASED *** MAINTAINS QUEUE WHICH KEEPS *** TRACK OF ALL THE DIFFERENT *** POSITIONS THE WORM HAS BEEN IN QUEUE LDA SEGLOC+2,Y ;LOAD 3RD,Y AND STA SEGLOC,Y ;STORE IT AT 0,Y POSITION IN THE QUEUE INY LDA SEGLOC+2,Y ;GET 3RD,Y AND STA SEGLOC,Y ;STORE IT AT 1ST,Y POSITION OF QUEUE INY DEX ;X REG CONTAINS LENGTH OF WORM TO DECREASE BNE QUEUE ;DONE WITH ALL SEGMENTS OF WORM IF <>0 THEN NO CLC BCC LESSER ;BRANCH ALWAYS GREATER DEC ADDLEN ;DEC # OF SEGMENTS TO ADD INC LENGTH ;INC LENGTH OF WORM INC HDPTR ;ADD TWO TO QUEUE HEAD POINTER INC HDPTR LESSER LDY #$00 DEC HDPTR ;SUBTRACT TWO FROM HEAD POINTER DEC HDPTR LDA (HDPTR),Y ;GET COORD OF SEGMENT BEHIND THE CURRENT HEAD STA X ;SAVE THEM PHA ; AND PUSH THEM ONTO STACK FOR LATER USE INC HDPTR LDA (HDPTR),Y ;GET Y COORD AND STA Y ;SAVE AND PHA ;PUSH IT ALSO INC HDPTR LDA #$EA ;NOP ERASING THE HEAD ON HIRES 1 STA DEL STA DEL+1 STA DEL1 STA DEL1+1 JSR SEGCLR ;ERASE SEGMENT ON PAGE 2 LDY #$00 CLC LDA X ;GET CURRENT HEAD POS ADC XI ;AND ADD X DIREC. VECTOR STA X ;SAVE IT STA (HDPTR),Y ;PUT ON THE BACK OF THE QUEUE INY CLC LDA Y ;GET CURR. Y ADC YJ ;ADD Y DIR. VECTOR STA Y ;SAVE AND STA (HDPTR),Y ;PUT ON BACK OF QUEUE JSR SEGTST ;TEST IF NEW HEAD WILL HIT ANYTHING LDA COLL ;GET COLLISION COUNTER BEQ NOCOLL ;EQUALS ZERO THAT'S GOOD JSR MORE1 ;ERASE THE APPLE AT ITS CURR. POSITION JSR SEGTST ;TEST NEW HEAD AGAIN LDA COLL ;TRY THE COLL. COUNTER AGAIN BNE DEAD ;NONZERO THIS TIME AND YOU DIE LDY POINT ;FIND OUT HOW MANY POINTS THE APPLE IS WORTH SCORUP JSR SCORE ;AND UPDATE THE SCORE ACCORDINGLY DEY BNE SCORUP LDA #$60 ;SET UP FOR NOISE FOR HITTING APPLE STA PITCH LDA #$64 STA EPITCH LDA #$03 STA TIME1 JSR SOUND DEC APCOUNT ;ONE LESS APPLE TO EAT BNE ADDL ;DONE WITH ALL TEN YET CLC BCC NOCOLL ;SKIP OVER DIE ROUTINE ADDL JSR MSAFE ;DRAW NEW MUSHROOM JSR SAFE ;DRAW NEW APPLE CLC LDA ADDLEN ;ADD 5 SEGMENTS TO WORM ADC #$05 STA ADDLEN CLC BCC NOCOLL ;SKIP DIE SEQUENCE DEAD JSR MORE1 ;REDRAW APPLE SINCE IT DID NOT CAUSE COLLISION NOCOLL LDA #$91 ;RESTORE SEGMENT ROUTINE TO NORMAL AFTER NOPS STA DEL STA DEL1 LDA #GRBUFFL STA DEL+1 STA DEL1+1 JSR SEGSET ;FINALLY DRAW THE NEW HEAD PLA ;GET COORD. OF HEAD SEGMENT THAT WAS ERASED STA Y ;AND REDAW IT. PLA STA X JSR SEGSET *** SEGSET,SEGCLR AND SEGTST *** DO ALL OPERATIONS ON THE *** WORM ITSELF. SEGSET JSR SSETUP ;GET PROPER SHIFTED SHAPE SDRAW LDY DELTAY ;GET CURRENT Y OFFSET JSR XYCALC ;CALCULATE MEMORY ADDRESS FOR HEAD LDY #$00 LDA WORM,X ;GET WORM'S SHAPE FROM TABLE ORA (GRBUFFL2),Y ;USE ORA FOR OVERLAPPING SEGMENTS STA (GRBUFFL),Y ;STORE ON PAGE 1 STA (GRBUFFL2),Y ;AND ON PAGE 2 INY INX LDA WORM,X ;SAME AS ABOVE SINCE THE WORM IS TWO BYTES WIDE ORA (GRBUFFL2),Y STA (GRBUFFL),Y STA (GRBUFFL2),Y INX INY INC DELTAY ;GO TO NEXT LINE ON SCREEN DEC DEPTH ;DONE WITH SHAPE YET? BNE SDRAW ;NO KEEP DOING MORE RTS SEGTST LDA #$00 ;INITIALIZE COLLISION COUNTER STA COLL JSR SSETUP ;GET SHIFTED SHAPE STST LDY DELTAY JSR XYCALC ;CALCULATE MEMORY ADDRESS LDY #$00 LDA WORM,X AND (GRBUFFL2),Y ;TEST PAGE TWO FOR COLLISIONS BEQ SKIP ;NONE GO ON INC COLL ;HIT SOMETHING INCREASE COLL SKIP INX INY LDA WORM,X AND (GRBUFFL2),Y ;DO THE SAME FOR THE SECOND BYTE OF WORM BEQ SKIP1 INC COLL SKIP1 INX INC DELTAY DEC DEPTH BNE STST RTS SEGCLR JSR SSETUP ;CALCULATE OFFSET SCLR LDY DELTAY JSR XYCALC LDY #$00 LDA WORM,X EOR #$FF ;COMPLEMENT WORM'S SHAPE AND (GRBUFFL),Y ;TO SIMULTATE A BIT CLEAR ROUTINE. DEL STA (GRBUFFL),Y ;A BIC OPCODE ON SOME MACHINES (PDP-11) STA (GRBUFFL2),Y ;EOR CAN NOT BE USED TO ERASE SHAPES BECAUSE INY ;OF THE OVERLAP IN THE SHAPES INX LDA WORM,X EOR #$FF AND (GRBUFFL),Y DEL1 STA (GRBUFFL),Y STA (GRBUFFL2),Y INY INX INC DELTAY DEC DEPTH BNE SCLR RTS SSETUP LDX X ;GET COORD. THAT WERE PASSED IN X,Y REG. LDY Y LDA XBASE,X ;GET THE BYTE OFFSET FROM TABLE STA DELTAX LDA XOFF,X ;GET THE BIT OFFSET FOR THE SHAPE TAX STY DELTAY ;STORE ABSOLUTE Y COORD. LDA #$07 STA DEPTH RTS XYCALC LDA TBL1,Y ;READS ADDRESS TABLES. CLC ADC DELTAX STA GRBUFFL STA GRBUFFL2 LDA TBL2,Y STA GRBUFFH LDA TBL3,Y STA GRBUFFH2 RTS *** SHAPESET DRAWS EITHER A MUSH- *** ROOM OR AN APPLE DEPENDING *** ON THE ADDRESS AT SHAPEL & *** SHAPEH. WORKS THE SAME AS THE *** OTHER SHAPE DRAWING ROUTINE SHAPESET JSR SHSETUP SHDRAW LDY DELTAY JSR XYCALC LDY #$00 SHDRAW2 INX NAME LDA MUSH,X EOR (GRBUFFL2),Y STA (GRBUFFL),Y STA (GRBUFFL2),Y INY CPY SLNGH BNE SHDRAW2 INC DELTAY CPX DEPTH BLT SHDRAW RTS SHSETUP STX DELTAX STY DELTAY LDX #$00 NAME1 LDA MUSH,X STA SLNGH INX NAME3 LDA MUSH,X STA DEPTH RTS SHTEST LDA #$00 ;TEST TO SEE WHETHER THE SHAPE WILL BE STA AMCOLL ;PLOTTED ON TOP OF SOMETHING ELSE JSR SHSETUP ;IF IT IS SAFE THEN AMCOLL RETURNS A ZERO SHTEST1 LDY DELTAY ;OTHERWISE IT IS NONZERO JSR XYCALC LDY #$00 SHTEST2 INX NAME2 LDA MUSH,X AND (GRBUFFL),Y BEQ SKIP2 INC AMCOLL SKIP2 INY CPY SLNGH BNE SHTEST2 INC DELTAY CPX #$2B BLT SHTEST1 RTS *** MSAFE & SAFE FIND A PLACE *** ON THE SCREEN FOR THE MUSH- *** ROOMS AND APPLES THAT IS NOT *** ALREADY OCCUPIED MSAFE JSR RANDOM ;CALLS APPLESOFT RANDOM ROUTINE LDA RNDL ;GET RND # AND #$1F ;MASKS OUT TOP FOUR BITS CLC ADC #$04 ;ADDS FOUR TO GIVE A VALUE BETWEEN 4 AND 20 STA MX ;SAVE IN X COORD. FOR SHAPE TAX LDA RNDH ;GETS OTHER RND # AND #$7F ;MASKS OUT HIGH BIT CLC ;ADDS 10 ADC #$0A ; TO GIVE A VALUE BETWEEN 10 AND 138 STA MY ;SAVE IN Y COORD TAY LDA #<MUSH ;INSTUCT DRAW ROUTINE THAT IT IS TO STA NAME+1 ;DRAW A MUSHROOM STA NAME1+1 STA NAME2+1 STA NAME3+1 JSR SHTEST ;TEST SHAPE AREA LDA AMCOLL ;IS THERE A COLLISION BEQ MORE ;NO THEN GO ON CLC BCC MSAFE ;YES, GET NEW COORD. AND TRY AGAIN MORE LDX MX ;GET (X,Y) OF MUSHROOM LDY MY JSR SHAPESET ;AND DRAW IT RTS SAFE JSR RANDOM ;SAFE WORKS THE SAME AS THE MSAFE ROUTINE LDA RNDL ;EXCEPT THAT THE RANDOM X IS ALWAYS AN EVEN # AND #$1E ;FOR A POSSIBLE COLOR APPLE AS A MODIFICATION CLC ADC #$04 CMP AX BEQ SAFE STA AX TAX LDA RNDH AND #$7F CLC ADC #$0A STA AY TAY LDA #<APPLE STA NAME+1 STA NAME1+1 STA NAME2+1 STA NAME3+1 JSR SHTEST LDA AMCOLL BEQ MORE1 CLC BCC SAFE MORE1 LDX AX LDY AY JSR SHAPESET RTS *** PARTIAL SCREEN CLEARS THE *** MIDDLE OF THE SCREEN. IT IS *** USED BETWEEN LEVELS. PSCRN LDX #$07 ;START SEVEN LINES DOWN BECAUSE OF THE BORDER NXTLIN LDA TBL1,X STA GRBUFFL STA GRBUFFL2 LDA TBL2,X STA GRBUFFH LDA TBL3,X STA GRBUFFH2 LDY #$02 ;START TWO BYTES OVER IN THE X DIREC. AGAIN BORD. NDONE LDA #$00 ;STORE ZEROS TO CLEAR STA (GRBUFFL),Y STA (GRBUFFL2),Y INY CPY #$26 ;UNTIL THE 38TH BYTE. LEAVES 2 BYTE BORDER BNE NDONE INX CPX #$A0 BNE NXTLIN RTS *** LEVELSET SETS UP THE LEVEL *** ACCORDING TO THE TEMPLATES *** LEVEL1,LEVEL2 ETC. IN THE *** THE TEMPLATES, IF A BIT IS *** ON THEN A BLOCK 7X7 PIXELS *** WILL BE DRAWN AT THAT *** LOCATION. LEVELSET LDY LCOUNT ;GET CURRENT LEVEL LDA TABLEL,Y ;GET ADDRESS OF CURRENT LEVEL TEMPLATE STA NODONE1+1 LDA TABLEH,Y STA NODONE1+2 LDY #$00 STY COUNT STY VERT LDA #$03 ;THREE BYTES MAKE ONE ROW (24 BITS) STA FINISH1 NODONE3 LDX VERT ;GET STARTING ADDRESS FROM ABBREV. LOOKUP TAB. LDA TABL1,X STA GRBUFFL STA GRBUFFL2 LDA TABL2,X STA GRBUFFH LDA TABL3,X STA GRBUFFH2 CLC ADC #$20 ;H BYTE OF ADDRESS TO STOP AT STA FINISH NODONE2 LDX COUNT LDY #$00 NODONE1 LDA LEVEL1,X ;GET BYTES OF TEMPLATE STA SHIFTER LDA #$08 ;EIGHT BITS IN A BYTE STA POS NODONE ASL SHIFTER ;SHIFT BITS INTO CARRY FLAG THEN TEST TO SEE BCC ZERO ;IF BITS ARE SET. IF NOT THE BRANCH LDA #$7F ;OTHERWISE FILL THE BYTE ON SCREEN STA (GRBUFFL),Y STA (GRBUFFL2),Y ZERO INY ;GO ON TO NEXT BIT DEC POS ;DONE WITH ALL EIGHT YET? BNE NODONE ;NO THEN GO FINISH INX ;DONE WITH THREE BYTES YET CPX FINISH1 ;NO THEN GO DO THAT BNE NODONE1 CLC LDA GRBUFFH ;CALCULATE NEXT HIRES ADDRESS RATHER THAN ADC #$04 ;LOOKING UP STA GRBUFFH CMP FINISH ;COMPARE TO FINISHING ADDRESS BNE NODONE2 ;NOT DONE YET DO MORE LDA FINISH1 ;STORE OLD FINISH MARKER IN COUNT STA COUNT CLC ADC #$03 ;UPDATE FINISH MARKER BY THREES TO KEEP TRACK STA FINISH1 ;OF THE END OF ROWS INC VERT ;NEXT LINE LDA VERT CMP #$0C ;DONE WITH ALL TWELVE YET? BNE NODONE3 ;NO THEN GO BACK RTS SCORE1 LDA #$40 ;SET UP SOUND ROUTINE STA PITCH ;FOR A BONUS SCORE LDA #$44 STA EPITCH LDA #$10 STA TIME1 STY TEMP JSR SOUND LDY TEMP LDA #$A0 JSR WAIT SCORE LDX #$03 MOSCO INC SCLOC,X ;KEEP SCORE DIRECTLY ON THE SCREEN BY LDA SCLOC,X ;INCREMENTING SCREEN LOCATIONS CMP #': BNE MORSC LDA #'0 STA SCLOC,X DEX CPX #$01 ;IF THE PLAYER GETS 10000 PTS BNE MOSCO INC LIFLOC ;GIVE HIM ANOTHER LIFE CLC BCC MOSCO MORSC RTS *** SOUND IS THE GENERAL PURPOSE *** SOUND ROUTINE THAT GENERATES *** A TONE OR SERIES OF TONES *** DEPENDING ON THE VALUES OF *** PITCH,TIME AND EPITCH (END- *** PITCH) SOUND LDA TIME1 STA TIME SOUND1 LDX PITCH LDA $C030 SOUND2 DEY BNE SOUND3 DEC TIME BEQ TEST SOUND3 DEX BNE SOUND2 BEQ SOUND1 TEST LDA PITCH CLC ADC #$04 STA PITCH CMP EPITCH BNE SOUND RTS MY HEX 00 MINSPD HEX 00 AMCOLL HEX 00 POS HEX 00 COUNT HEX 00 FINISH HEX 00 VERT HEX 00 AX HEX 00 AY HEX 00 COLL HEX 00 TEMP HEX 00 DIE? HEX 00 EPITCH HEX 00 TIME1 HEX 00 POINT HEX 00 FINISH1 HEX 00