; XXXXXXX XXXXXXXX XX XXXXXX XXXXXXXX ; XXX XXX XXX XXX XXXX XXX XXX XXX ; XXX XXX XXX XXX XX XXX XXX ; XXX XXX XXX XXX XX XXX XXX ; XXX XXX XXX XXX XX XXX XXXXXX ; XXX XXX XXX XXX XX XXX XXX ; XXX XXXXXXXX XXX XX XXX XXX ; XXX XXX XXXXXXXXXXXXXXXX XXX XXX ; XXX XXX XXX XXX XX XXX XXX XXX ; XXXXXX XXX XXX XX XXXXXX XXXXXXXX ; ; XX XX XX XX XX XX XXXX XXXXXX XXXXXX XXXX ; XX XXX XX XX XX XXXX XX XX XX XX XX XX ; XX XX XX XX XX XX XX XX XX XX XXXX XX XX XX ; XX XX XXX XXXX XXXXXXXX XX XX XX XXXXXX XX ; XX XX XX XX XX XX XXXX XXXXXX XX XX XXXX ; ; XXXX XXXXXX XX XX XX XX XX XXXXXX ; XX XX XX XX XX XX XX XX XX ; XX XX XXXX XX XX XX XX XXXX ; XX XX XX XX XX XX XX XX XX ; XXXX XXXXXX XXXXXX XXXXXX XX XX XXXXXX ; ;Space Invaders Deluxe ;Hack by: Kurt(Nukey Shay)Howe ;Original program: ;Space Invaders ;By: Rick Maurer (c) 1980 Atari ;Special thanks to: ;Franklin(NE146)Cruz' 'Space Invaders' for paving the way ;Rob(raindog)Kudla's 'Space Invaders Arcade' for refining that idea ;Jeff(Yak)Minter's 'Beast Invaders' for supplying double-shot capability ;Albert(Albert)Yarusso, Alex(Alex)Bilstein, and AtariAge.com... ;for giving us all a place to show off ;) ;And the members of AtariAge.com for playtesting and support! ; ;Hack history: ;03/17/04 Flashing missiles, additional mothership added, "rainbow" bonus added. ;03/18/04 Difficulty switches changed, line added to represent "Earth", colorbars added. ;03/19/04 Explosion animation removed. ;03/20/04 Sounds altered, shot counting added. ;03/21/04 End-of-movement markers fixed. ;03/26/04 Final 4k build. ;10/04/04 Binary size doubled to 8k, 1st intermission added, mothership animations added. ;10/27/04 5-digit scoring implemented. ;11/27/04 Title marquee added. ;11/30/04 System stack eliminated. ;12/04/04 Onscreen point values shown for hit invaders/motherships. ;01/17/05 NTSC/PAL palette switching implemented. ;03/04/05 Pause function added (to the intermission kernal only). ;03/05/05 Hit sound altered, missile size altered, "rainbow" bonus sound added. ;09/20/05 7800 autodetect added, 2nd intermission added, true shot count! ;09/21/05 Display cleaned up (visible "attract" area reduced, HMOVE line now invisible). ;09/24/05 High Score function added (single-player and co-op variations). ;09/25/05 True rainbow bonus, player-independant shot counting capability. ;09/26/05 Invader GFX altered (3 new types), mothership now always enabled. ;09/27/05 High score routine moved, additional title display color tables, markers altered, ; original SI lives bug (that displays 1 life left in 2-player attract mode) corrected, ; title screen and intermission screen skip routines added. ; ;Instructions: ; Game variations follow the original manual with these exceptions: ; ; Console switches: ; *Color/B&W is used to toggle NTSC/PAL60 modes (except while the power-up title is displayed). ; *Left difficulty selects the base width of BOTH players. ; *Right difficulty selects between single and double shots (in non-simultanous variations). ; ; Scoring: ; *Points per invader are 30, 30, 20, 20, 10, and 10 (top row to bottom). In addition... ; *500-point bonus awarded for hitting a lowest invader last (1000 if from leftmost column). ; *500-point bonus awarded for hitting next-from-lowest invader last (leftmost column only). ; *Mothership values range from 50 to 300 points, the blinking mothership worth 500 points. ; ; Cosmetic: ; *A game title marquee is shown momentarily upon powerup. This display can be skipped by ; moving any direction on either joystick (also see 'Gameplay' below). ; *Game colors and sprite shapes altered to approximate coin-op "Deluxe"/"Part II" versions. ; *Display altered to keep track of up to 99,990 points each player (instead of only 9,990)! ; *The right score color (indicating # of players for that game variation) will be displayed ; in RED if that variation includes the high-score function...YELLOW if not. All single- ; player and co-op variations include the function. The high score is cleared if GAME SELECT ; is used at any time. ; *End-of-movement markers altered to indicate the number of player bases remaining. ; ; Gameplay: ; *One of two "intermissions" will appear following the completion of each board...during ; which gameplay can be suspended indefinately by pressing a controller button. Press again ; to resume. Intermissions can be skipped individually by moving a stick or using any console ; switch. The intermission display can be disabled completely by holding the RIGHT joystick ; in the DOWN direction when the powerup title display is shown. ; ; New strategies: ; *Blinking motherships: ; The blinking motherships are only allowed to appear when an internal 4-bit missile counter ; rolls to zero, and are always worth 500 points instead of a random value. Missile counters ; begin with a value of 1 for each player when a new game is started...so 15 more shots are ; required to make the blinking craft appear (and 16 shots following that, etc.). By keeping ; track of how many shots are fired, you can force this craft to appear every time. Seperate ; counters are used for each player during 2-player competition (non-simultanous) play. ; NOTE: The blinking craft cannot be struck by a missile when it is momentarily invisible. ; *The "rainbow" bonus: ; You collect bonus points if you can shoot a low invader (out of the original 36) last! ; Since the leftmost column has two bonus point invaders available instead of only one, you ; can better your odds of getting one by going after the other columns first and finishing ; the round with that column. Because player 1 begins the round under this column, you may ; find it to your advantage to begin a 2-player game instead and use the right (yellow) base, ; which begins each round under the rightmost column of invaders. ; ; ; ; ; ; ; Disassembly of sia.bin ; Disassembled Tue Mar 16 23:27:53 2004 ; Using DiStella v2.0 ; ; Command Line: C:\BIN\DISTELLA.EXE -pafscsi.cfg sia.bin ; ; si.cfg contents: ; CODE F000 FBFD ; GFX FBFE FD66 ; CODE FD67 FF4B ; GFX FF4C FFFB ; ; current .cfg contents: ;Bank 1... ; CODE D000 DAF8 ; GFX DAF9 DFF0 ; CODE DFF1 DFF4 ; GFX DFF5 DFFF ;Bank 2... ; CODE F000 FCAB ; GFX FCAC FFF0 ; CODE FFF1 FFF7 ; GFX FFF8 FFFF ; ; processor 6502 ;hardware register equates VSYNC = $00 ;Vertical Sync Set-Clear VBLANK = $01 ;Vertical Blank Set-Clear WSYNC = $02 ;Wait for Horizontal Blank RSYNC = $03 ;Reset Horizontal Sync Counter NUSIZ0 = $04 ;Number-Size player/missle 0 NUSIZ1 = $05 ;Number-Size player/missle 1 COLUP0 = $06 ;Color-Luminance Player 0 COLUP1 = $07 ;Color-Luminance Player 1 COLUPF = $08 ;Color-Luminance Playfield COLUBK = $09 ;Color-Luminance Background CTRLPF = $0A ;Control Playfield, Ball, Collisions REFP0 = $0B ;Reflection Player 0 REFP1 = $0C ;Reflection Player 1 PF0 = $0D ;Playfield Register Byte 0 (upper nybble used only) PF1 = $0E ;Playfield Register Byte 1 PF2 = $0F ;Playfield Register Byte 2 RESP0 = $10 ;Reset Player 0 RESP1 = $11 ;Reset Player 1 RESM0 = $12 ;Reset Missle 0 RESM1 = $13 ;Reset Missle 1 RESBL = $14 ;Reset Ball ;Audio registers AUDC0 = $15 ;Audio Control - Voice 0 (distortion) AUDC1 = $16 ;Audio Control - Voice 1 (distortion) AUDF0 = $17 ;Audio Frequency - Voice 0 AUDF1 = $18 ;Audio Frequency - Voice 1 AUDV0 = $19 ;Audio Volume - Voice 0 AUDV1 = $1A ;Audio Volume - Voice 1 ;Sprite registers GRP0 = $1B ;Graphics Register Player 0 GRP1 = $1C ;Graphics Register Player 1 ENAM0 = $1D ;Graphics Enable Missle 0 ENAM1 = $1E ;Graphics Enable Missle 1 ENABL = $1F ;Graphics Enable Ball HMP0 = $20 ;Horizontal Motion Player 0 HMP1 = $21 ;Horizontal Motion Player 1 HMM0 = $22 ;Horizontal Motion Missle 0 HMM1 = $23 ;Horizontal Motion Missle 1 HMBL = $24 ;Horizontal Motion Ball VDELP0 = $25 ;Vertical Delay Player 0 VDELP1 = $26 ;Vertical Delay Player 1 VDELBL = $27 ;Vertical Delay Ball RESMP0 = $28 ;Reset Missle 0 to Player 0 RESMP1 = $29 ;Reset Missle 1 to Player 1 HMOVE = $2A ;Apply Horizontal Motion HMCLR = $2B ;Clear Horizontal Move Registers CXCLR = $2C ;Clear Collision Latches Waste1 = $2D ;Unused Waste2 = $2E ;Unused Waste3 = $2F ;Unused ;collisions (bit 7) (bit 6) CXM0P = $30 ;Read Collision - M0-P1 M0-P0 CXM1P = $31 ;Read Collision - M1-P0 M1-P1 CXP0FB = $32 ;Read Collision - P0-PF P0-BL CXP1FB = $33 ;Read Collision - P1-PF P1-BL CXM0FB = $34 ;Read Collision - M0-PF M0-BL CXM1FB = $35 ;Read Collision - M1-PF M1-BL CXBLPF = $36 ;Read Collision - BL-PF ----- CXPPMM = $37 ;Read Collision - P0-P1 M0-M1 INPT0 = $38 ;Read Pot Port 0 INPT1 = $39 ;Read Pot Port 1 INPT2 = $3A ;Read Pot Port 2 INPT3 = $3B ;Read Pot Port 3 INPT4 = $3C ;Read Input - Trigger 0 (bit 7) INPT5 = $3D ;Read Input - Trigger 1 (bit 7) ;RIOT registers SWCHA = $0280 ;Port A data register for joysticks (High nybble:player0,low nybble:player1) SWACNT = $0281 ;Port A data direction register (DDR) SWCHB = $0282 ;Port B data (console switches) bit pattern LR--B-SR SWBCNT = $0283 ;Port B data direction register (DDR) INTIM = $0284 ;Timer output TIMINT = $0285 ; WasteA = $0286 ;Unused/undefined WasteB = $0287 ;Unused/undefined WasteC = $0288 ;Unused/undefined WasteD = $0289 ;Unused/undefined WasteE = $028A ;Unused/undefined WasteF = $028B ;Unused/undefined WasteG = $028C ;Unused/undefined WasteH = $028D ;Unused/undefined WasteI = $028E ;Unused/undefined WasteJ = $028F ;Unused/undefined WasteK = $0290 ;Unused/undefined WasteL = $0291 ;Unused/undefined WasteM = $0292 ;Unused/undefined WasteN = $0293 ;Unused/undefined TIM1T = $0294 ;set 1 clock interval TIM8T = $0295 ;set 8 clock interval TIM64T = $0296 ;set 64 clock interval T1024T = $0297 ;set 1024 clock interval Invaders = $91 ;# of invaders left for current player Mship = $C9 Framecount = $CA Variation = $DC Score = $E6 P1scoreHi = Score P2scoreHi = Score+1 P1scoreLo = Score+2 P2scoreLo = Score+3 ;ram assignment changes Icolor = $DD Temp = $DE ColorShift = $DF Ctrl = $FA DifSw = $FB Mask = $FC Lives = $FD ;bit0-1=lives, bit2=intermission autoskip (set in boot sequence). ;bits 7,4,3=pointer to bonus score gfx,bit5=P1 bonus double flag,bit6=hiscore flag FLAG2 = $FE ;bit4=Mystery ship,bit5=P2 bonus double flag,bit6=PAL/NTSC,bit7=console type,low nybble free SHOT = $FF ;nybble shot counter ;intermission ram (all shared) PrintTemp = $AB TempCounter = $EB TempGFX = $CC PlayerX = $CB ShipPos = $C8 ShipMem = $9D Trigger = $9C OldTrigger = $9B ShipWaits = $9A ;constants: ;colors YEAR = $98 SKY = $00 ;Begin first bank ORG $1000 RORG $D000 LD000: sta $1FF9 ;4 go back to second bank ;check score color lda FLAG2 ;3 and #$40 ;2 tax ;2 bit Lives ;3 bvs LD00D ;2 inx ;2 LD00D: lda YELLOW,x ;4 sta COLUP1 ;3 LD012: lda INTIM ;4 bne LD012 ;2 sta VBLANK ;3 enable TIA sta CXCLR ;3 ldx #$00 ;2 ;mothership disable lda Framecount ;3 and #$18 ;2 lsr ;2 lsr ;2 sta Temp ;3 lda #$EA ;2 sta WSYNC ;3 sta TIM64T ;4 sta HMCLR ;3 bit $AA ;3 bmi LD03B ;2 ;check mothership lda $9E ;3 cmp #$B4 ;2 beq LD03B ;2 jmp LD113 ;3 jump to display mothership LD03B: jmp LD984 ;3 jump to display score LD03E: stx Waste2 ;3 dec $89 ;5 lda $89 ;3 bmi LD055 ;2 cmp #$03 ;2 lda #$02 ;2 bcc LD04D ;2 lsr ;2 LD04D: sta ENABL ;3 sta WSYNC ;3 sta HMCLR ;3 bpl LD072 ;2 LD055: clc ;2 adc $8A ;3 sta $89 ;3 lda #$00 ;2 sta WSYNC ;3 sta HMCLR ;3 sta ENABL ;3 lda $88 ;3 sta HMBL ;3 and #$0F ;2 tay ;2 LD069: dey ;2 bpl LD069 ;2 sta RESBL ;3 lda #$7C ;2 sta $8A ;3 LD072: sta WSYNC ;3 sta HMOVE ;3 stx Waste2 ;3 jmp LD421 ;3 LD07B: sta WSYNC ;3 lda FLAG2 ;3 and #$40 ;2 eor #$40 ;2 tay ;2 lda CYAN,y ;4 get P1 base/score color sta COLUP0 ;3 lda #$02 ;2 sta CTRLPF ;3 lda #$04 ;2 sta $EE ;3 lda #$DF ;2 sta $EF ;3 bit $AA ;3 bmi LD09D ;2 lda #$FF ;2 bne LD09F ;2 LD09D: txa ;2 NOP ;2 LD09F: sta.w Mask ;4 ;invisible ldy Icolor ;3 lda ColorShift ;3 bne LD0AC ;2 ldy #$05 ;2<- adjusted invisible color bne LD0AE ;2 LD0AC: NOP ;2 NOP ;2 LD0AE: sty Icolor ;3 LD0B0: ldy $F0 ;3 lda ($EE),y ;5 lsr ;2 sta PF0 ;3 NOP ;2 stx PF1 ;3 ldy $EE ;3 lda UTdigits,y ;4 and Mask ;3 ldy $F5 ;3 ora ($EE),y ;5 lsr ;2 sta PF2 ;3 ldy $F2 ;3 lda ($EE),y ;5 sta PF0 ;3 ldy $EE ;3 lda UTdigits,y ;4 and Mask ;3 ldy $F7 ;3 ora ($EE),y ;5 sta PF2 ;3 ldy $F4 ;3 lda ($EE),y ;5 sta $81 ;3 ldy $F1 ;3 lda ($EE),y ;5 ora $81 ;3 asl ;2 sta PF1 ;3 NOP ;2 stx PF0 ;3 stx PF2 ;3 ldy $F6 ;3 lda ($EE),y ;5 sta $81 ;3 ldy $F3 ;3 lda ($EE),y ;5 ora $81 ;3 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 sta PF1 ;3 dec $EE ;5 bpl LD0B0 ;2 lda $89 ;3 clc ;2 adc #$F9 ;2 sta $89 ;3 NOP ;2 stx PF1 ;3 jmp LD1A7 ;3 ;bugfix...correct ground during UFO LD113: cmp #$0F ;2 bcs LD119 ;2 sta WSYNC ;3 LD119: cmp #$20 ;2 bcs LD11F ;2 sta WSYNC ;3 LD11F: ldy #$FF ;2 sec ;2 don't remove LD122: iny ;2 sbc #$0F ;2 bcs LD122 ;2 eor #$FF ;2 sbc #$06 ;2 asl ;2 asl ;2 asl ;2 asl ;2 sty $83,x ;4 ora $83,x ;4 sta $83,x ;4 sta WSYNC ;3 NOP ;2 iny ;2 sta HMP0,x ;4 NOP ;2 LD13C: dey ;2 bpl LD13C ;2 sta RESP0,x ;4 dec $89 ;5 lda $89 ;3 ldx #$02 ;2 cmp #$03 ;2 bcc LD14D ;2 ldx #$00 ;2 LD14D: stx ENABL ;3 ldx Temp ;3 ;shot check lda FLAG2 ;3 and #$10 ;2 bne LD158 ;2 branch if mystery ship inx ;2 blinking LD158: lda MothershipGFXtbl,x ;4 sta $EE ;3 lda #>MothershipGFX ;2 sta $EF ;3 lda #$00 ;2 sta NUSIZ0 ;3 sta WSYNC ;3 sta HMOVE ;3 lda $C8 ;3 and #$39 ;2 cmp #$39 ;2 bne LD178 ;2 ldy Mship ;3 lda MothershipScoreGFXtbl,y ;4 sta $EE ;3 LD178: sta WSYNC ;3 sta HMCLR ;3 dec $89 ;5 lda $89 ;3 ldy #$02 ;2 cmp #$03 ;2 bcc LD188 ;2 ldy #$00 ;2 LD188: sty ENABL ;3 ldy #$08 ;2 LD18C: sta WSYNC ;3 lda ($EE),y ;5 sta GRP0 ;3 tya ;2 lsr ;2 bcs LD1A4 ;2 dec $89 ;5 lda $89 ;3 ldx #$02 ;2 cmp #$03 ;2 bcc LD1A2 ;2 ldx #$00 ;2 LD1A2: stx ENABL ;3 LD1A4: dey ;2 bpl LD18C ;2 LD1A7: lda #$00 ;2 sta WSYNC ;3 sta GRP0 ;3 lda $84 ;3 sta HMP1 ;3 sta HMP0 ;3 and #$0F ;2 tay ;2 LD1B6: dey ;2 bpl LD1B6 ;2 sta RESP0 ;3 lda #$06 ;2 sta RESP1 ;3 sta WSYNC ;3 sta HMOVE ;3 sta NUSIZ0 ;3 sta NUSIZ1 ;3 ldx #$0A ;2 lda #>SpriteGFX ;2 <-invaders LD1CB: sta $EF,x ;4 dex ;2 dex ;2 bpl LD1CB ;2 dec $89 ;5 lda $89 ;3 ldy #$02 ;2 cmp #$03 ;2 bcc LD1DD ;2 ldy #$00 ;2 LD1DD: sty ENABL ;3 lda WSYNC ;3 and #$40 ;2 sta $82 ;3 sta CXCLR ;3 sta HMCLR ;3 lda #$F0 ;2 sta HMP1 ;3 sta WSYNC ;3 sta HMOVE ;3 LD1F1: dec $8F ;5 bpl LD200 ;2 ldy #$05 ;2 lda #$01 ;2 sta VDELP0 ;3 sta VDELP1 ;3 jmp LD2E5 ;3 LD200: jmp LDA35 ;3 LD203: stx $EE ;3 inx ;2 lda $C7 ;3 asl ;2 asl ;2 clc ;2 adc $C7 ;3 clc ;2 adc #$59 ;2 sta $C7 ;3 and #$20 ;2 bne LD218 ;2 dex ;2 dex ;2 LD218: cpx #$08 ;2 bcs LD226 ;2 lda $C7 ;3 cmp #$C0 ;2 bcc LD226 ;2 lda ($F0),y ;5 sta ($F0),y ;6 LD226: ldx $EE ;3 lda ($F0),y ;5 and LDD79,x ;4 sta ($F0),y ;6 jmp LD636 ;3 LD232: sta HMCLR ;3 lda $84 ;3 horizontal position bmi LD238 ;2 (req'd) LD238: and #$0F ;2 tax ;2 LD23B: dex ;2 bpl LD23B ;2 LD23E: lda ($F8),y ;5 tax ;2 lda ($EE),y ;5 sta GRP0 ;3 lda ($F0),y ;5 sta GRP1 ;3 lda ($F2),y ;5 sta GRP0 ;3 lda ($F4),y ;5 sta GRP1 ;3 lda ($F6),y ;5 sta GRP0 ;3 txa ;2 sta GRP1 ;3 sta GRP0 ;3 dec $89 ;5 dey ;2 ;waste 14 cycles NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 lda ($F8),y ;5 tax ;2 lda ($EE),y ;5 sta GRP0 ;3 lda ($F0),y ;5 sta GRP1 ;3 lda ($F2),y ;5 sta GRP0 ;3 lda ($F4),y ;5 sta GRP1 ;3 lda ($F6),y ;5 sta GRP0 ;3 txa ;2 sta GRP1 ;3 sta GRP0 ;3 lda $89 ;3 cmp #$04 ;2 bcc LD28A ;2 lda #$00 ;2 bcs LD28D ;2 LD28A: NOP ;2 lda #$02 ;2 LD28D: sta.w ENABL ;4 dey ;2 bpl LD23E ;2 iny ;2 sty GRP0 ;3 sty GRP1 ;3 sty HMCLR ;3 sty GRP0 ;3 sty GRP1 ;3 sta WSYNC ;3 dec $89 ;5 lda $89 ;3 cmp #$03 ;2 bcc LD2AB ;2 tya ;2 A/Y=0 bcs LD2AE ;2 LD2AB: NOP ;2 lda #$02 ;2 LD2AE: sta ENABL ;3 ldy $80 ;3 dec Icolor ;5 switch to next color band lda WSYNC ;3 ora RSYNC ;3 asl ;2 bmi LD2C1 ;2 NOP ;2 waste NOP ;2 waste sta Waste2 ;3 waste bpl LD2C8 ;2 always branch LD2C1: lda $82 ;3 ora LDE61,y ;4 sta $82 ;3 LD2C8: sta CXCLR ;3 dey ;2 dec $8C ;5 bpl LD2D7 ;2 lda #$00 ;2 sta VDELP0 ;3 sta VDELP1 ;3 beq LD34E ;2 always branch LD2D7: dec $89 ;5 lda $89 ;3 ldx #$02 ;2 cmp #$03 ;2 bcc LD2E3 ;2 ldx #$00 ;2 LD2E3: stx ENABL ;3 LD2E5: sty $80 ;3 lda.wy $92,y ;4 sta $F8 ;3 ldx #$F4 ;2 LD2EE: lsr $F8 ;5 bcc LD2F9 ;2 lda InvaderGFXtbl,y ;4 adc $8B ;3 bne LD2FF ;2 ;change invaders to point GFX LD2F9: lda Lives ;3 and #$98 ;2 keep only bits 7,4, and 8 (A=$00, $90, or $98) NOP ;2 NOP ;2 LD2FF: sta Ctrl,x ;4 inx ;2 inx ;2 bmi LD2EE ;2 dec $89 ;5 lda $89 ;3 ldx #$02 ;2 cmp #$03 ;2 bcc LD311 ;2 ldx #$00 ;2 LD311: stx ENABL ;3 lda $C8 ;3 and #$38 ;2 lsr ;2 lsr ;2 lsr ;2 cmp $80 ;3 bne LD332 ;2 lda $C8 ;3 and #$07 ;2 asl ;2 tax ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 NOP ;2 lda #TextGFX ;2 sta $AC,x ;4 dey ;2 dex ;2 dex ;2 bpl LF917 ;2 lda INPT5 ;3 rol ;2 lda INPT4 ;3 ror ;2 and #$C0 ;2 tax ;2 cpx $9B ;3 beq LF93C ;2 cpx #$C0 ;2 beq LF93C ;2 lda $9C ;3 eor #$80 ;2 sta $9C ;3 LF93C: stx $9B ;3 lda #$00 ;2 sta AUDV1 ;3 ldy #$07 ;2 ldx #$07 ;2 sta WSYNC ;3 LF948: dex ;2 bne LF948 ;2 sta RESP0 ;3 lda #$93 ;2 sta RESP1 ;3 sta HMP0 ;3 sty HMP1 ;3 sta NUSIZ0 ;3 sta NUSIZ1 ;3 ldx #$0A ;2 LF95B: lda INTIM ;4 bne LF95B ;2 sta VBLANK ;3 sta WSYNC ;3 sta HMOVE ;3 stx COLUP0 ;3 stx COLUP1 ;3 stx $EB ;3 dex ;2 dex ;2 NOP ;2 LF96F: dex ;2 bpl LF96F ;2 LF972: ldy $EB ;3 lda ($AB),y ;5 sta GRP0 ;3 bit VSYNC ;3 lda ($AD),y ;5 sta GRP1 ;3 lda ($B5),y ;5 tax ;2 txs ;2 lda ($AF),y ;5 sta $CC ;3 lda ($B1),y ;5 tax ;2 lda ($B3),y ;5 ldy $CC ;3 sty GRP0 ;3 stx GRP1 ;3 sta GRP0 ;3 tsx ;2 stx GRP1 ;3 dec $EB ;5 bpl LF972 ;2 lda $CB ;3 NOP ;2 NOP ;2 tay ;2 and #$0F ;2 sta WSYNC ;3 tax ;2 lda #$00 ;2 sta COLUP0 ;3 sta COLUP1 ;3 sty HMP1 ;3 NOP ;2 dex ;2 LF9AE: dex ;2 bpl LF9AE ;2 sta RESP1 ;3 sta WSYNC ;3 sta HMOVE ;3 txs ;2 inx ;2 stx NUSIZ0 ;3 stx NUSIZ1 ;3 stx GRP0 ;3 stx GRP1 ;3 lda P2scoreHi ;3 eor P1scoreLo ;3 and #$03 ;2 bit FLAG2 ;3 bvs LF9CD ;2 ora #$04 ;2 LF9CD: tay ;2 lda IntermissionColorTbl,y ;4 sta COLUP1 ;3 ldy #>EscapeShip1 ;2 sty $9E ;3 lda Framecount ;3 and #$04 ;2 asl ;2 beq LF9E0 ;2 ora #$01 ;2 ship gfx index = 0 or 9 LF9E0: sta WSYNC ;3 tay ;2 lda P2scoreHi ;3 eor P1scoreLo ;3 and #$02 ;2 beq LFA3D ;2 tya ;2 ora #$20 ;2 alternate ship gfx #$20 from 1st tay ;2 lda Framecount ;3 bpl LFA3D ;2 bit $9A ;3 bpl LFA3D ;2 ldy #$20 ;2 kill animation when jettisoned ;"engine trouble" 2nd part sty $9D ;3 eor #$FF ;2 lsr ;2 tay ;2 bpl LFA03 ;2 LFA01: sta WSYNC ;3 LFA03: dey ;2 bpl LFA01 ;2 ldy #$08 ;2 LFA08: lda ($9D),y ;5 sta GRP1 ;3 sta WSYNC ;3 dey ;2 cpy #$03 ;2 bne LFA08 ;2 stx GRP1 ;3 lda Framecount ;3 sec ;2 sbc #$7E ;2 lsr ;2 tax ;2 LFA1C: sta WSYNC ;3 ldy #$00 ;2 txa ;2 and #$03 ;2 bne LFA27 ;2 ldy #$42 ;2 LFA27: sty GRP1 ;3 dex ;2 bne LFA1C ;2 ldy #$04 ;2 LFA2E: lda ($9D),y ;5 sta GRP1 ;3 sta WSYNC ;3 dey ;2 bpl LFA2E ;2 stx GRP1 ;3 ldy #$41 ;2 bne LFA5D ;2 always branch ;regular intermissions ("S.O.S!" and "Engine trouble" part 1) LFA3D: sty $9D ;3 lda Framecount ;3 eor #$FF ;2 lsr ;2 tay ;2 LFA45: sta WSYNC ;3 dey ;2 bpl LFA45 ;2 ldy #$09 ;2 LFA4C: lda ($9D),y ;5 sta GRP1 ;3 sta WSYNC ;3 dey ;2 bpl LFA4C ;2 stx GRP1 ;3 lda Framecount ;3 lsr ;2 tay ;2 LFA5B: sta WSYNC ;3 LFA5D: dey ;2 bpl LFA5B ;2 lda #$50 ;2 sta TIM64T ;4 lda Framecount ;3 bpl LFA6F ;2 lda $9D ;3 cmp #