Combat NTSC
This is the NTSC version of the code.
F000: 78 SEI ; Turn off interrupts F001: D8 CLD ; Binary mode (not BCD) F002: A2 FF LDX #$FF ; Stack pointer to 1_FF ... F004: 9A TXS ; ... ghosts to 0_FF F005: A2 5D LDX #$5D ; Clear memory ... F007: 20 BD F5 JSR $F5BD ; ... 00 through A2 (hardware registers and game variables) F00A: A9 10 LDA #$10 ; Console switches are all ... F00C: 8D 83 02 STA SWBCNT ; ... inputs (D4 is not used) F00F: 85 88 STA m88 ; ?? Is this the debounce? F011: 20 A3 F1 JSR $F1A3 ;
Main Game Loop
main: F014: 20 32 F0 JSR StartTVFrame ; Start the next TV frame F017: 20 57 F1 JSR $F157 ; ?? switches ?? F01A: 20 72 F5 JSR $F572 ; ?? pro switches ?? F01D: 20 DA F2 JSR $F2DA ; F020: 20 44 F4 JSR $F444 ; ?? Collisions ?? F023: 20 14 F2 JSR $F214 ; F026: 20 A9 F2 JSR $F2A9 ; F029: 20 F2 F1 JSR ScoreGraphics ; Convert the player scores to graphics offsets F02C: 20 54 F0 JSR DrawVisible ; Draw the screen F02F: 4C 14 F0 JMP main ; Back to top of main loop
Start the TV Frame
StartTVFrame: ; Increment the frame counter and trigger the vertical sync. ; The timer is set to time the blanking period. F032: E6 86 INC frameCounter ; Bump the frame counter F034: 85 2B STA HMCLR ; Clear horizontal motion registers F036: A9 02 LDA #$02 ; D1 bit ON F038: 85 02 STA WSYNC ; Wait for the end of the current line F03A: 85 01 STA VBLANK ; Turn the electron beam off F03C: 85 02 STA WSYNC ; Wait for all ... F03E: 85 02 STA WSYNC ; ... the electrons ... F040: 85 02 STA WSYNC ; ... to drain out F042: 85 00 STA VSYNC ; Trigger the vertical sync signal F044: 85 02 STA WSYNC ; Hold for ... F046: 85 02 STA WSYNC ; ... two scan lines F048: A9 00 LDA #$00 ; D1 bit OFF F04A: 85 02 STA WSYNC ; Hold for a third line F04C: 85 00 STA VSYNC ; Release the vertical sync signal F04E: A9 2B LDA #$2B ; Set timer to 43*64 = 2752 machine ... F050: 8D 96 02 STA TIM64T ; ... cycles 2752/(228/3) = 36 scanlines F053: 60 RTS ; Done
Draw the Visible Screen
DrawVisible: ; ; TODO Blurb on Frame 30 and the key ; F054: A9 20 LDA #$20 ; Start counting at 32 ... F056: 85 B4 STA scanlineNumber ; ... makes the playfield math easier F058: 85 02 STA WSYNC ; Wait for the end of the current line (ensure HMOVE is in the horiz blanking) F05A: 85 2A STA HMOVE ; Apply horizontal movement to all objects F05C: AD 84 02 LDA INTIM ; Wait for the visible TV to ... F05F: D0 FB BNE $F05C ; ... reach the visible area F061: 85 02 STA WSYNC ; 37th scanline F063: 85 2C STA CXCLR ; Clear the collision flags F065: 85 01 STA VBLANK ; Turn the electron beam back on F067: BA TSX ; Save stack ... F068: 86 D3 STX stackPointer ; ... pointer F06A: A9 02 LDA #$02 ; Playfield left/right color of P0/P1 F06C: 85 0A STA CTRLPF ; ... on top? F06E: A6 DC LDX mDC ; F070: 85 02 STA WSYNC ; F072: CA DEX ; F073: D0 FB BNE $F070 ; F075: A5 DC LDA mDC ; ?? F077: C9 0E CMP #$0E F079: F0 52 BEQ $F0CD ; Skip drawing the top numbers F07B: A2 05 LDX #$05 ; 5 rows per digit F07D: A9 00 LDA #$00 ; Clear ... F07F: 85 DE STA nextLeft ; ... next pattern for left two digits F081: 85 DF STA nextRight ; Clear next pattern for right two digits ; ; Loop for drawing digits ; From Z26 log for frame 30 ; Lines 42 through 53 ; ; 42| *.|.....................................................| At F083 ; ; Loop from F083 to F0CA ; 43|...1...................|.............1........................*..............| First pass - blanks ; 44|.........1.............|................1.....*..............................| Digit row 1 ; ; 45|...1...................|.............1........................*..............| Duplicate row 1 ; 46|.........1.............|................1.....*..............................| Digit row 2 ; 47|...1...................|.............1........................*..............| Duplicate row 2 ; 48|.........1.............|................1.....*..............................| Digit row 3 ; 49|...1...................|.............1........................*..............| Duplicate row 3 ; 50|.........1.............|................1.....*..............................| Digit row 4 ; 51|...1...................|.............1........................*..............| Duplicate row 4 ; 52|.........1.............|................1.....*..............................| Digit row 5 ; 53|...1...................|.............1........................*..............| Duplicate row 5 ; ; 54|.........1.........1..*|.....................................................| Digit ... aborted at F0CD ; F083: 85 02 STA WSYNC ; 42 21 {-hard_WSYNC} Wait for next row F085: A5 DE LDA nextLeft ; 43 0 {-ram_nextLeft} Digit graphics calculated last row F087: 85 0E STA PF1 ; 43 3 {-hard_PF1} Duplicate the left number from last row F089: A4 E2 LDY leftDigitMSD ; 43 6 {-ram_leftDigitMSD} Index to left number left digit F08B: B9 C5 F5 LDA $F5C5,Y ; 43 9 Get graphics for digit F08E: 29 F0 AND #$F0 ; 43 13 Only the left part of the pattern F090: 85 DE STA nextLeft ; 43 15 {-ram_nextLeft} New graphics for left number F092: A4 E0 LDY leftDigitLSD ; 43 18 {-ram_leftDigitLSD} Index to left number right digit F094: B9 C5 F5 LDA $F5C5,Y ; 43 21 Get graphics for digit F097: 29 0F AND #$0F ; 43 25 Only the right part of the pattern F099: 05 DE ORA nextLeft ; 43 27 {-ram_nextLeft} Combine left and right digits F09B: 85 DE STA nextLeft ; 43 30 {-ram_nextLeft} We'll use it next row ; F09D: A5 DF LDA nextRight ; 43 33 {-ram_nextRight} Digit graphics calculated last row F09F: 85 0E STA PF1 ; 43 36 {-hard_PF1} ** Duplicate the right number from last row F0A1: A4 E3 LDY rightDigitMSD ; 43 39 {-ram_rightDigitMSD} Index to right number left digit F0A3: B9 C5 F5 LDA $F5C5,Y ; 43 42 Get graphics for digit F0A6: 29 F0 AND #$F0 ; 43 46 Only the left part of the pattern F0A8: 85 DF STA nextRight ; 43 48 {-ram_nextRight} New graphics for right number F0AA: A4 E1 LDY rightDigitLSD ; 43 51 {-ram_rightDigitLSD} Index to the right number right digit F0AC: B9 C5 F5 LDA $F5C5,Y ; 43 54 Get graphics for digit F0AF: 25 87 AND maskRightNumber ; 43 58 {-ram_maskRightNumber} Blank the right number right digit if in game-select F0B1: 85 02 STA WSYNC ; 43 61 {-hard_WSYNC} Wait for next row ; F0B3: 05 DF ORA nextRight ; 44 0 {-ram_nextRight} Combine left and right digits F0B5: 85 DF STA nextRight ; 44 3 {-ram_nextRight} We'll use it later on this row F0B7: A5 DE LDA nextLeft ; 44 6 {-ram_nextLeft} Get the newly calculated graphics F0B9: 85 0E STA PF1 ; 44 9 {-hard_PF1} Draw the new left number F0BB: CA DEX ; 44 12 All digit rows done? F0BC: 30 0F BMI $F0CD ; 44 14 Yes ... done ; On the last row we write a bogus value for the first number, but we quickly clear it out at F0CD before ; it gets drawn F0BE: E6 E0 INC leftDigitLSD ; 44 16 {-ram_leftDigitLSD} Next row in left digit LSD F0C0: E6 E2 INC leftDigitMSD ; 44 21 {-ram_leftDigitMSD} Next row in left digit MSD F0C2: E6 E1 INC rightDigitLSD ; 44 26 {-ram_rightDigitLSD} Next row in right digit LSD F0C4: E6 E3 INC rightDigitMSD ; 44 31 {-ram_rightDigitMSD} Next row in right digit MSD F0C6: A5 DF LDA nextRight ; 44 36 {-ram_nextRight} Get the newly calculated graphics F0C8: 85 0E STA PF1 ; 44 39 {-hard_PF1} ** Draw the right number F0CA: 4C 83 F0 JMP $F083 ; 44 42 Back for all rows of digits ; ; Draw the play area F0CD: A9 00 LDA #$00 ; 54 17 Clear the score for ... F0CF: 85 0E STA PF1 ; 54 19 {-hard_PF1} ... next row F0D1: 85 02 STA WSYNC ; 54 22 {-hard_WSYNC} Make a blank line ; ; 55|..W.....C.....c | | ; F0D3: A9 05 LDA #$05 ; 55 0 Playfield over players and ... F0D5: 85 0A STA CTRLPF ; 55 2 {-hard_CTRLPF} 55 2 ... reflect playfield F0D7: A5 D6 LDA colorP0 ; 55 5 {-ram_colorP0} 55 5 Set color ... F0D9: 85 06 STA COLUP0 ; 55 8 {-hard_COLUP0} 55 8 ... player 0 F0DB: A5 D7 LDA colorP1 ; 55 11 {-ram_colorP1} 55 11 Set color ... F0DD: 85 07 STA COLUP1 ; 55 14 {-hard_COLUP1} 55 14 ... player 1 ; ; Top of loop ; ; Same loop for the rest of the screen, but at 155 we are in the middle of the screen ; where the players are. Let's pick up the video timing at the top of the loop midway ; across the scanline 155. ; 155| | .........................*........| ; 156|X..........u..........t|....................................................Y| ; 157|.........0.......1.....|..2.........................................*........| ; ; Using the stackpointer here to speed up the writes. ; We start pointing to ENAM1 and work lower in memory. ; This is the playing area where the players and missiles are. F0DF: A2 1E LDX #$1E ; 155 42 Pointer to ... F0E1: 9A TXS ; 155 44 ... ENAM1 ; ;Player 0 ; F0E2: 38 SEC ; 155 46 Clear the borrow flag F0E3: A5 A4 LDA player0row ; 155 48 {-ram_player0row} Player 0's row number F0E5: E5 B4 SBC scanlineNumber ; 155 51 {-ram_scanlineNumber} Compare it to the current row ; To speed up the lookup, the players graphics are interleaved. Even rows ; are for player 0 and odd rows are for player 1. F0E7: 29 FE AND #$FE ; 155 54 Even is for player 0 F0E9: AA TAX ; 155 56 Hold the graphics pointer F0EA: 29 F0 AND #$F0 ; 155 68 Within the 16 row window? F0EC: F0 04 BEQ $F0F2 ; 155 60 Yes ... draw the player F0EE: A9 00 LDA #$00 ; No player 0 graphics on this row F0F0: F0 02 BEQ $F0F4 ; JMP $F0F4 F0F2: B5 BD LDA playerXpicture,X ; 155 63 {-ram_playerXpicture} 155 63 Get the graphics for this row F0F4: 85 02 STA WSYNC ; 155 67 {-hard_WSYNC} 155 67 Wait for next row F0F6: 85 1B STA GRP0 ; 156 0 {-hard_GRP0} 156 0 Draw player 0 on this row ; ; Missile 1 ; F0F8: A5 A7 LDA missile1row ; 156 3 {-ram_missile1row} Missile 1 row F0FA: 45 B4 EOR scanlineNumber ; 156 6 {-ram_scanlineNumber} Compare it to the current row F0FC: 29 FE AND #$FE ; 156 9 Odd and even rows (doubling) ; The Z flag is in the D1 position of the status register. This maps to ; D1 of the Enable-Missile-1. Thus when the current row is the same as the ; missile the Z flag will be set and will enable the missile with the push. F0FE: 08 PHP ; 156 11 Turn missile 1 on or off ; ; Missile 0 ; F0FF: A5 A6 LDA missile0row ; 156 14 {-ram_missile0row} Missile 0 row F101: 45 B4 EOR scanlineNumber ; 156 17 {-ram_scanlineNumber} Compare it to the current row F103: 29 FE AND #$FE ; 156 20 Odd and even rows (doubling) F105: 08 PHP ; 156 22 Turn missile 0 on or off ; ; Playfield graphics pointers. ; ; The playfield pattern is a table of 12 entries. This loop runs the table forwards with ; each entry drawn over 8 rows. 8*12 = 96 rows. Then the loop runs the table backwards ; with each entry drawn over 8 rows. 96 rows again. The bottom of the screen reflects ; the top. ; ; The reflection happens with the upper bit of the row count in B4. Positive values are the ; upper half of the screen. Negative values are the lower half. The number "12", as in ; twelve entries, is difficult to work with but "16" is easy. The math assumes the table ; is 16 values and starts with the fourth value. The loop uses entries 4-16 on the positive ; top half. Then 16-4 on the bottom half. The graphics pointers are backed up 4 bytes so ; that the table looks like 16 bytes. B4 starts at 32 (32/8=4) at the top half of the ; screen. In the bottom half the check at F10C keeps the code from drawing the bogus ; values in the table entries 3, 2, 1, and 0. ; F106: A5 B4 LDA scanlineNumber ; 156 25 {-ram_scanlineNumber} Current row F108: 10 02 BPL $F10C ; 156 28 We are in the top (non reflected) region ; $B4 is 80, scanline 152 F10A: 49 F8 EOR #$F8 ; 156 30 Reflection: run the table backwards from 15 F10C: C9 20 CMP #$20 ; 156 32 At the bottom of the screen just use ... F10E: 90 04 BCC $F114 ; 156 34 ... the last pattern over and over ; Playfield graphics are 8-rows tall F110: 4A LSR A ; 156 36 Divide ... F111: 4A LSR A ; 156 38 ... by ... F112: 4A LSR A ; 156 40 ... 8 (each playfield value covers 8 rows) F113: A8 TAY ; 156 42 Graphics offset to Y for later ; F114: A5 A5 LDA player1row ; 156 44 {-ram_player1row} Player 1's row number F116: 38 SEC ; 156 47 Clear the borrow flag (this is how 6502 works) F117: E5 B4 SBC scanlineNumber ; 156 49 {-ram_scanlineNumber} Compare the row numbers F119: E6 B4 INC scanlineNumber ; 156 52 {-ram_scanlineNumber} Bump to next row (doubling) F11B: EA NOP ; 156 57 ?? Timing ? F11C: 09 01 ORA #$01 ; 156 59 Odd is for player 1 F11E: AA TAX ; 156 61 Hold the graphics pointer F11F: 29 F0 AND #$F0 ; 156 63 Within the 16 row window? F121: F0 04 BEQ $F127 ; 156 65 Yes ... draw the player F123: A9 00 LDA #$00 ; No player 1 graphics on this row F125: F0 02 BEQ $F129 ; JMP $F129 F127: B5 BD LDA playerXpicture,X ; 156 68 {-ram_playerXpicture} Get the graphics for this row F129: 24 82 BIT skipPlayfield ; 156 72 {-ram_skipPlayfield} Bit 7 goes to the M flag F12B: 85 1C STA GRP1 ; 156 75 {-hard_GRP1} Draw player 1 on this row ; F12D: 30 0C BMI $F13B ; 157 2 If D7 of $82 is set, skip the playfield F12F: B1 B5 LDA (pf0Graphics),Y ; 157 4 {-ram_pf0Graphics} Copy the ... F131: 85 0D STA PF0 ; 157 9 {-hard_PF0} ... PF0 graphics F133: B1 B7 LDA (pf1Graphics),Y ; 157 12 {-ram_pf1Graphics} Copy the ... F135: 85 0E STA PF1 ; 157 17 {-hard_PF1} ... PF1 graphics F137: B1 B9 LDA (pf2Graphics),Y ; 157 20 {-ram_pf2Graphics} Copy the ... F139: 85 0F STA PF2 ; 157 25 {-hard_PF2} ... PF2 graphics F13B: E6 B4 INC scanlineNumber ; 157 28 {-ram_scanlineNumber} Next row (we are doing 2 at a time) F13D: A5 B4 LDA scanlineNumber ; 157 33 {-ram_scanlineNumber} Have we done all ... F13F: 49 EC EOR #$EC ; 157 36 ... 236 rows? F141: D0 9C BNE $F0DF ; 157 38 No ... go back for more ; ; End of frame ; ; 258|x..........u..........t|.............................................y.......| ; 259|..0.......1.......2....|...............t..u..x..y..x..0..1..2... | ; ?? See the "x..y..x" on this last line? Why clear the GRP0 twice ?? ; F143: A6 D3 LDX stackPointer ; 259 33 {-ram_stackPointer} Restore the ... F145: 9A TXS ; 259 36 ... stack pointer ; We just EORed with EC (11101100) and checked for zero. ; The only way we get a zero is when A = EC, which means D1 is ; zero for the stores below. F146: 85 1D STA ENAM0 ; 259 38 {-hard_ENAM0} Turn off missile 0 F148: 85 1E STA ENAM1 ; 259 41 {-hard_ENAM1} Turn off missile 1 F14A: 85 1B STA GRP0 ; 259 44 {-hard_GRP0} Turn off player 0 F14C: 85 1C STA GRP1 ; 259 47 {-hard_GRP1} Turn off player 1 F14E: 85 1B STA GRP0 ; 259 50 {-hard_GRP0} Turn off player 0 (?? why again) F150: 85 0D STA PF0 ; 259 53 {-hard_PF0} Turn off playfield 0 F152: 85 0E STA PF1 ; 259 56 {-hard_PF1} Turn off playfield 1 F154: 85 0F STA PF2 ; 259 59 {-hard_PF2} Turn off playfield 2 F156: 60 RTS ; 259 62 Done ; ?? Called from main loop F157: AD 82 02 LDA SWCHB ; Console switches F15A: 4A LSR A ; RESET switch to carry F15B: B0 13 BCS $F170 ; 1 means NOT pressed ... skip F15D: A9 0F LDA #$0F ; No longer blanking ... F15F: 85 87 STA maskRightNumber ; ... the right digit for P1 score F161: A9 FF LDA #$FF F163: 85 88 STA m88 ; F165: A9 80 LDA #$80 F167: 85 DD STA mDD ; F169: A2 E6 LDX #$E6 F16B: 20 BD F5 JSR $F5BD ; F16E: F0 60 BEQ $F1D0 ; JMP F1D0 ; F170: A0 02 LDY #$02 F172: A5 DD LDA mDD ; F174: 25 88 AND m88 ; F176: C9 F0 CMP #$F0 F178: 90 08 BCC $F182 ; F17A: A5 86 LDA frameCounter ; F17C: 29 30 AND #$30 F17E: D0 02 BNE $F182 ; F180: A0 0E LDY #$0E ; F182: 84 DC STY mDC ; F184: A5 86 LDA frameCounter ; F186: 29 3F AND #$3F F188: D0 08 BNE $F192 ; F18A: 85 89 STA m89 ; F18C: E6 DD INC mDD ; F18E: D0 02 BNE $F192 ; F190: 85 88 STA m88 ; F192: AD 82 02 LDA SWCHB ; Console switches F195: 29 02 AND #$02 ; SELECT pressed? F197: F0 04 BEQ $F19D ; 0 means YES F199: 85 89 STA m89 ; F19B: D0 54 BNE $F1F1 ; JMP F1F1 ; F19D: 24 89 BIT m89 ; F19F: 30 50 BMI $F1F1 ; F1A1: E6 80 INC m80 ; ; ?? Called before main loop ... initialization? F1A3: A2 DF LDX #$DF F1A5: 20 BD F5 JSR $F5BD ; F1A8: A9 FF LDA #$FF F1AA: 85 89 STA m89 ; F1AC: A4 80 LDY m80 ; F1AE: B9 D8 F7 LDA $F7D8,Y ; F1B1: 85 A3 STA mA3 ; F1B3: 49 FF EOR #$FF F1B5: D0 04 BNE $F1BB ; F1B7: A2 DD LDX #$DD F1B9: D0 EA BNE $F1A5 ; F1BB: A5 81 LDA m81 ; F1BD: F8 SED F1BE: 18 CLC F1BF: 69 01 ADC #$01 F1C1: 85 81 STA m81 ; F1C3: 85 A1 STA scoreP1 ; F1C5: D8 CLD F1C6: 24 A3 BIT mA3 ; F1C8: 10 06 BPL $F1D0 ; F1CA: E6 85 INC m85 ; F1CC: 50 02 BVC $F1D0 ; F1CE: E6 85 INC m85 ; F1D0: 20 25 F5 JSR $F525 ; F1D3: A9 32 LDA #$32 F1D5: 85 A5 STA player1row ; F1D7: A9 86 LDA #$86 F1D9: 85 A4 STA player0row ; F1DB: 24 A3 BIT mA3 ; F1DD: 30 12 BMI $F1F1 ; F1DF: 85 A5 STA player1row ; F1E1: 85 11 STA RESP1 ; RESP1:28,11 F1E3: A9 08 LDA #$08 F1E5: 85 96 STA m96 ; F1E7: A9 20 LDA #$20 F1E9: 85 20 STA HMP0 ; HMP0:29,12 F1EB: 85 21 STA HMP1 ; HMP1:29,12 F1ED: 85 02 STA WSYNC ; WSYNC:29,12 F1EF: 85 2A STA HMOVE ; HMOVE:30,13 F1F1: 60 RTS ScoreGraphics: ; Convert the score values in A1 to 5-byte digit offsets in E0,E2 ; Convert the score values in A2 to 5-byte digit offsets in E1,E3 F1F2: A2 01 LDX #$01 ; Loop over 1 and 0 ... score for each player F1F4: B5 A1 LDA scoreP1,X ; Get score F1F6: 29 0F AND #$0F ; Just the lower digit F1F8: 85 D2 STA scratch1 ; We will add this back to make 5 F1FA: 0A ASL A ; Digit * 2 F1FB: 0A ASL A ; Digit * 4 F1FC: 18 CLC ; No carry F1FD: 65 D2 ADC scratch1 ; Digit * 5 F1FF: 95 E0 STA leftDigitLSD,X ; Store offset F201: B5 A1 LDA scoreP1,X ; Get score again F203: 29 F0 AND #$F0 ; Upper digit this time F205: 4A LSR A ; Digit*16 / 2 = Digit*8 F206: 4A LSR A ; Digit*4 F207: 85 D2 STA scratch1 ; Hold Digit*4 F209: 4A LSR A ; Digit*2 F20A: 4A LSR A ; Digit*1 F20B: 18 CLC ; No carry F20C: 65 D2 ADC scratch1 ; Now Digit*5 F20E: 95 E2 STA leftDigitMSD,X ; Store offset F210: CA DEX ; Loop back for ... F211: 10 E1 BPL $F1F4 ; ... players 1 and 0 F213: 60 RTS ; Done ; ?? Called from main loop F214: 24 83 BIT m83 ; F216: 50 04 BVC $F21C ; F218: A9 30 LDA #$30 F21A: 10 02 BPL $F21E ; F21C: A9 20 LDA #$20 F21E: 85 B1 STA mB1 ; F220: A2 03 LDX #$03 F222: 20 54 F2 JSR $F254 ; F225: CA DEX F226: 20 54 F2 JSR $F254 ; F229: CA DEX F22A: B5 8D LDA m8D,X ; F22C: 29 08 AND #$08 F22E: 4A LSR A F22F: 4A LSR A F230: 86 D1 STX mD1 ; F232: 18 CLC F233: 65 D1 ADC mD1 ; F235: A8 TAY F236: B9 A8 00 LDA mA8,Y ; F239: 38 SEC F23A: 30 01 BMI $F23D ; F23C: 18 CLC F23D: 2A ROL A F23E: 99 A8 00 STA mA8,Y ; F241: 90 0D BCC $F250 ; F243: B5 AC LDA mAC,X ; F245: 29 01 AND #$01 F247: 0A ASL A F248: 0A ASL A F249: 0A ASL A F24A: 0A ASL A F24B: 85 B1 STA mB1 ; F24D: 20 54 F2 JSR $F254 ; F250: CA DEX F251: F0 D7 BEQ $F22A ; F253: 60 RTS F254: F6 AC INC mAC,X ; F256: B5 95 LDA m95,X ; F258: 29 0F AND #$0F F25A: 18 CLC F25B: 65 B1 ADC mB1 ; F25D: A8 TAY F25E: B9 F7 F5 LDA $F5F7,Y ; ??DATA?? F261: 85 B0 STA mB0 ; F263: 24 82 BIT skipPlayfield ; F265: 70 13 BVS $F27A ; F267: B5 95 LDA m95,X ; F269: 38 SEC F26A: E9 02 SBC #$02 F26C: 29 03 AND #$03 F26E: D0 0A BNE $F27A ; F270: B5 AC LDA mAC,X ; F272: 29 03 AND #$03 F274: D0 04 BNE $F27A ; F276: A9 08 LDA #$08 F278: 85 B0 STA mB0 ; F27A: A5 B0 LDA mB0 ; F27C: 95 20 STA HMP0,X ; HMP0:28,20,22 HMP1:26,18,19 HMM1:lots HMM0:lots F27E: 29 0F AND #$0F F280: 38 SEC F281: E9 08 SBC #$08 F283: 85 D4 STA mD4 ; F285: 18 CLC F286: 75 A4 ADC player0row,X ; F288: 24 A3 BIT mA3 ; F28A: 30 04 BMI $F290 ; F28C: E0 02 CPX #$02 F28E: B0 10 BCS $F2A0 ; F290: C9 DB CMP #$DB F292: B0 04 BCS $F298 ; F294: C9 25 CMP #$25 F296: B0 08 BCS $F2A0 ; F298: A9 D9 LDA #$D9 F29A: 24 D4 BIT mD4 ; F29C: 30 02 BMI $F2A0 ; F29E: A9 28 LDA #$28 F2A0: 95 A4 STA player0row,X ; F2A2: E0 02 CPX #$02 F2A4: B0 02 BCS $F2A8 ; F2A6: 95 25 STA VDELP0,X ; VDELP1:27,26,19,20 VDELP0:29,21,22 F2A8: 60 RTS ; ?? Called from main loop F2A9: A9 01 LDA #$01 F2AB: 25 86 AND frameCounter ; F2AD: AA TAX F2AE: B5 95 LDA m95,X ; F2B0: 95 0B STA REFP0,X ; REFP1:20,19,18,21 REFP0:lots F2B2: 29 0F AND #$0F F2B4: A8 TAY F2B5: 24 83 BIT m83 ; F2B7: 10 02 BPL $F2BB ; F2B9: 94 97 STY m97,X ; F2BB: 8A TXA F2BC: 49 0E EOR #$0E F2BE: AA TAX F2BF: 98 TYA F2C0: 0A ASL A F2C1: 0A ASL A F2C2: 0A ASL A F2C3: C9 3F CMP #$3F F2C5: 18 CLC F2C6: 30 03 BMI $F2CB ; F2C8: 38 SEC F2C9: 49 47 EOR #$47 F2CB: A8 TAY F2CC: B1 BB LDA (mBB),Y ; F2CE: 95 BD STA playerXpicture,X ; F2D0: 90 02 BCC $F2D4 ; F2D2: 88 DEY F2D3: 88 DEY F2D4: C8 INY F2D5: CA DEX F2D6: CA DEX F2D7: 10 F3 BPL $F2CC ; F2D9: 60 RTS ; ?? Called from main loop F2DA: A5 8A LDA m8A ; F2DC: 38 SEC F2DD: E9 02 SBC #$02 F2DF: 90 2B BCC $F30C ; F2E1: 85 8A STA m8A ; F2E3: C9 02 CMP #$02 F2E5: 90 24 BCC $F30B ; F2E7: 29 01 AND #$01 F2E9: AA TAX F2EA: F6 95 INC m95,X ; F2EC: B5 D8 LDA mD8,X ; F2EE: 95 D6 STA colorP0,X ; F2F0: A5 8A LDA m8A ; F2F2: C9 F7 CMP #$F7 F2F4: 90 03 BCC $F2F9 ; F2F6: 20 08 F5 JSR $F508 ; F2F9: A5 8A LDA m8A ; F2FB: 10 0E BPL $F30B ; F2FD: 4A LSR A F2FE: 4A LSR A F2FF: 4A LSR A F300: 95 19 STA AUDV0,X ; AUDV0:12,13 F302: A9 08 LDA #$08 F304: 95 15 STA AUDC0,X ; AUDC0:12,13 F306: BD FE F7 LDA $F7FE,X ; Negative number?? F309: 95 17 STA AUDF0,X ; AUDF0:12,13 F30B: 60 RTS F30C: A2 01 LDX #$01 F30E: AD 82 02 LDA SWCHB ; SWCHB:7,16,14 F311: 85 D5 STA mD5 ; F313: AD 80 02 LDA SWCHA ; SWCHA:7,16,14 F316: 24 88 BIT m88 ; F318: 30 02 BMI $F31C ; F31A: A9 FF LDA #$FF F31C: 49 FF EOR #$FF F31E: 29 0F AND #$0F F320: 85 D2 STA scratch1 ; F322: A4 85 LDY m85 ; F324: B9 0F F7 LDA $F70F,Y ; F327: 18 CLC F328: 65 D2 ADC scratch1 ; F32A: A8 TAY F32B: B9 12 F7 LDA $F712,Y ; F32E: 29 0F AND #$0F F330: 85 D1 STA mD1 ; F332: F0 04 BEQ $F338 ; F334: D5 91 CMP m91,X ; F336: D0 04 BNE $F33C ; F338: D6 93 DEC m93,X ; F33A: D0 0D BNE $F349 ; F33C: 95 91 STA m91,X ; F33E: A9 0F LDA #$0F F340: 95 93 STA m93,X ; F342: A5 D1 LDA mD1 ; F344: 18 CLC F345: 75 95 ADC m95,X ; F347: 95 95 STA m95,X ; F349: F6 8D INC m8D,X ; F34B: 30 1E BMI $F36B ; F34D: B9 12 F7 LDA $F712,Y ; F350: 4A LSR A F351: 4A LSR A F352: 4A LSR A F353: 4A LSR A F354: 24 D5 BIT mD5 ; F356: 30 23 BMI $F37B ; F358: 95 8B STA m8B,X ; F35A: 0A ASL A F35B: A8 TAY F35C: B9 37 F6 LDA $F637,Y ; F35F: 95 A8 STA mA8,X ; F361: C8 INY F362: B9 37 F6 LDA $F637,Y ; F365: 95 AA STA mAA,X ; F367: A9 F0 LDA #$F0 F369: 95 8D STA m8D,X ; F36B: 20 80 F3 JSR $F380 ; F36E: AD 80 02 LDA SWCHA ; SWCHA:lots F371: 4A LSR A F372: 4A LSR A F373: 4A LSR A F374: 4A LSR A F375: 06 D5 ASL mD5 ; F377: CA DEX F378: F0 9C BEQ $F316 ; F37A: 60 RTS F37B: 38 SEC F37C: E5 85 SBC m85 ; F37E: 10 D8 BPL $F358 ; F380: A5 A3 LDA mA3 ; F382: 30 08 BMI $F38C ; F384: 29 01 AND #$01 F386: F0 04 BEQ $F38C ; F388: A5 DB LDA mDB ; F38A: 95 D6 STA colorP0,X ; F38C: B5 99 LDA m99,X ; F38E: F0 27 BEQ $F3B7 ; F390: B5 D8 LDA mD8,X ; F392: 95 D6 STA colorP0,X ; F394: B5 99 LDA m99,X ; F396: C9 07 CMP #$07 F398: 90 14 BCC $F3AE ; F39A: 24 D5 BIT mD5 ; F39C: 10 04 BPL $F3A2 ; F39E: C9 1C CMP #$1C F3A0: 90 0C BCC $F3AE ; F3A2: C9 30 CMP #$30 F3A4: 90 1F BCC $F3C5 ; F3A6: C9 37 CMP #$37 F3A8: B0 21 BCS $F3CB ; F3AA: 24 83 BIT m83 ; F3AC: 50 1D BVC $F3CB ; F3AE: A9 00 LDA #$00 F3B0: 95 99 STA m99,X ; F3B2: A9 FF LDA #$FF F3B4: 95 28 STA RESMP0,X ; RESMP1:10,18,19,17 RESMP0:lots F3B6: 60 RTS F3B7: 24 88 BIT m88 ; F3B9: 10 04 BPL $F3BF ; F3BB: B5 3C LDA INPT4,X ; INPT5:9 INPT4:11,12 F3BD: 10 37 BPL $F3F6 ; F3BF: 20 10 F4 JSR $F410 ; F3C2: 4C AE F3 JMP $F3AE ; F3C5: 20 10 F4 JSR $F410 ; F3C8: 4C DE F3 JMP $F3DE ; F3CB: B5 9F LDA m9F,X ; F3CD: F0 0A BEQ $F3D9 ; F3CF: 20 10 F4 JSR $F410 ; F3D2: A9 30 LDA #$30 F3D4: 95 99 STA m99,X ; F3D6: 4C DE F3 JMP $F3DE ; F3D9: B5 99 LDA m99,X ; F3DB: 20 00 F3 JSR $F300 ; F3DE: A5 86 LDA frameCounter ; F3E0: 29 03 AND #$03 F3E2: F0 0C BEQ $F3F0 ; F3E4: 24 84 BIT m84 ; F3E6: 70 0A BVS $F3F2 ; F3E8: 24 82 BIT skipPlayfield ; F3EA: 50 04 BVC $F3F0 ; F3EC: 29 01 AND #$01 F3EE: D0 02 BNE $F3F2 ; F3F0: D6 99 DEC m99,X ; F3F2: A9 00 LDA #$00 F3F4: F0 BE BEQ $F3B4 ; F3F6: A9 3F LDA #$3F F3F8: 95 99 STA m99,X ; F3FA: 38 SEC F3FB: B5 A4 LDA player0row,X ; F3FD: E9 06 SBC #$06 F3FF: 95 A6 STA missile0row,X ; F401: B5 95 LDA m95,X ; F403: 95 97 STA m97,X ; F405: A9 1F LDA #$1F F407: 95 9B STA m9B,X ; F409: A9 00 LDA #$00 F40B: 95 9D STA m9D,X ; F40D: 4C CB F3 JMP $F3CB ; F410: B5 9F LDA m9F,X ; F412: F0 0D BEQ $F421 ; F414: A9 04 LDA #$04 F416: 95 15 STA AUDC0,X ; F418: A9 07 LDA #$07 F41A: 95 19 STA AUDV0,X ; F41C: B5 9B LDA m9B,X ; F41E: 95 17 STA AUDF0,X ; F420: 60 RTS F421: A4 85 LDY m85 ; F423: B9 33 F7 LDA $F733,Y ; F426: 25 88 AND m88 ; F428: 95 19 STA AUDV0,X ; AUDV0:13,12,21,19 AUDV1:10,9,18,16 F42A: B9 36 F7 LDA $F736,Y ; F42D: 95 15 STA AUDC0,X ; AUDC1:10,9,18,16 AUDC0:13,12,21,19 F42F: 18 CLC F430: A9 00 LDA #$00 F432: 88 DEY F433: 30 04 BMI $F439 ; F435: 69 0C ADC #$0C F437: 10 F9 BPL $F432 ; F439: 75 8B ADC m8B,X ; F43B: A8 TAY F43C: 8A TXA F43D: 0A ASL A F43E: 79 39 F7 ADC $F739,Y ; F441: 95 17 STA AUDF0,X ; AUDF1:10,9,18,17 AUDF0:lots F443: 60 RTS ; ?? Called from main loop F444: A2 01 LDX #$01 ; Start with Player 1 (back again from F504) F446: B5 30 LDA CXM0P,X ; Collisions between this player's missile and other player F448: 10 2C BPL $F476 ; D7 clear -- this player's missile did not hit other player F44A: 24 84 BIT m84 ; F44C: 50 06 BVC $F454 ; F44E: B5 9B LDA m9B,X ; F450: C9 1F CMP #$1F F452: F0 22 BEQ $F476 ; F454: F6 95 INC m95,X ; F456: F6 97 INC m97,X ; ; F458: F8 SED ; BCD mode for 2-digit score F459: B5 A1 LDA scoreP1,X ; Player score F45B: 18 CLC ; No carry F45C: 69 01 ADC #$01 ; Give 1 point ... F45E: 95 A1 STA scoreP1,X ; ... to player F460: D8 CLD ; Out of BCD mode for normal math ; F461: 8A TXA F462: 18 CLC F463: 69 FD ADC #$FD F465: 85 8A STA m8A ; F467: A9 FF LDA #$FF F469: 85 28 STA RESMP0 ; F46B: 85 29 STA RESMP1 ; F46D: A9 00 LDA #$00 F46F: 95 19 STA AUDV0,X ; F471: 85 99 STA m99 ; F473: 85 9A STA m9A ; F475: 60 RTS ; F476: 24 A3 BIT mA3 ; F478: 10 03 BPL $F47D ; F47A: 4C 01 F5 JMP $F501 ; F47D: B5 9F LDA m9F,X ; F47F: F0 0A BEQ $F48B ; F481: C9 04 CMP #$04 F483: F6 9F INC m9F,X ; F485: 90 04 BCC $F48B ; F487: A9 00 LDA #$00 F489: 95 9F STA m9F,X ; F48B: B5 34 LDA CXM0FB,X ; Collisions between this player's missile and the playfield F48D: 30 07 BMI $F496 ; Bit set ... this player's missile hit the playfield F48F: A9 00 LDA #$00 F491: 95 9D STA m9D,X ; F493: 4C D6 F4 JMP $F4D6 ; ; F496: 24 82 BIT skipPlayfield ; F498: 50 36 BVC $F4D0 ; F49A: B5 9D LDA m9D,X ; F49C: D0 19 BNE $F4B7 ; F49E: F6 9F INC m9F,X ; F4A0: D6 9B DEC m9B,X ; F4A2: B5 97 LDA m97,X ; F4A4: 95 B2 STA mB2,X ; F4A6: 49 FF EOR #$FF F4A8: 95 97 STA m97,X ; F4AA: F6 97 INC m97,X ; F4AC: B5 97 LDA m97,X ; F4AE: 29 03 AND #$03 F4B0: D0 02 BNE $F4B4 ; F4B2: F6 97 INC m97,X ; F4B4: 4C D4 F4 JMP $F4D4 ; F4B7: C9 01 CMP #$01 F4B9: F0 0B BEQ $F4C6 ; F4BB: C9 03 CMP #$03 F4BD: 90 15 BCC $F4D4 ; F4BF: D0 13 BNE $F4D4 ; F4C1: B5 B2 LDA mB2,X ; F4C3: 4C C8 F4 JMP $F4C8 ; F4C6: B5 97 LDA m97,X ; F4C8: 18 CLC F4C9: 69 08 ADC #$08 F4CB: 95 97 STA m97,X ; F4CD: 4C D4 F4 JMP $F4D4 ; ; F4D0: A9 01 LDA #$01 F4D2: 95 99 STA m99,X ; F4D4: F6 9D INC m9D,X ; F4D6: B5 32 LDA CXP0FB,X ; Collisions between this player and the playfield F4D8: 30 04 BMI $F4DE ; Bit set ... this player hit the playfield F4DA: A5 37 LDA CXPPMM ; Collisions between players F4DC: 10 09 BPL $F4E7 ; Bit is clear ... no collisions F4DE: A5 8A LDA m8A ; F4E0: C9 02 CMP #$02 F4E2: 90 09 BCC $F4ED ; F4E4: 20 08 F5 JSR $F508 ; F4E7: A9 03 LDA #$03 F4E9: 95 E4 STA mE4,X ; F4EB: D0 14 BNE $F501 ; F4ED: D6 E4 DEC mE4,X ; F4EF: 30 06 BMI $F4F7 ; F4F1: B5 8B LDA m8B,X ; F4F3: F0 0C BEQ $F501 ; F4F5: D0 02 BNE $F4F9 ; F4F7: F6 95 INC m95,X ; F4F9: B5 95 LDA m95,X ; F4FB: 18 CLC F4FC: 69 08 ADC #$08 F4FE: 20 0F F5 JSR $F50F ; F501: CA DEX F502: 30 03 BMI $F507 ; F504: 4C 46 F4 JMP $F446 ; F507: 60 RTS F508: 8A TXA F509: 49 01 EOR #$01 F50B: A8 TAY F50C: B9 97 00 LDA m97,Y ; F50F: 29 0F AND #$0F F511: A8 TAY F512: B9 27 F6 LDA $F627,Y ; F515: 20 7C F2 JSR $F27C ; F518: A9 00 LDA #$00 F51A: 95 A8 STA mA8,X ; F51C: 95 AA STA mAA,X ; F51E: 95 8D STA m8D,X ; F520: B5 D8 LDA mD8,X ; F522: 95 D6 STA colorP0,X ; F524: 60 RTS F525: A6 85 LDX m85 ; Player type (0=tank, 1=jet, 2=plane) F527: BD C6 F7 LDA PlayerPicLSB,X ; Get picture ... F52A: 85 BB STA mBB ; ... pointer LSB F52C: BD C9 F7 LDA PlayerPicMSB,X ; Get picture ... F52F: 85 BC STA mBC ; ... pointer MSB F531: A5 A3 LDA mA3 ; F533: 4A LSR A F534: 4A LSR A F535: 29 03 AND #$03 F537: AA TAX F538: A5 A3 LDA mA3 ; F53A: 10 0A BPL $F546 ; F53C: 29 08 AND #$08 F53E: F0 04 BEQ $F544 ; F540: A2 03 LDX #$03 F542: 10 04 BPL $F548 ; F544: A9 80 LDA #$80 F546: 85 82 STA skipPlayfield ; F548: A5 A3 LDA mA3 ; F54A: 0A ASL A F54B: 0A ASL A F54C: 24 A3 BIT mA3 ; F54E: 30 06 BMI $F556 ; F550: 85 02 STA WSYNC ; WSYNC:27,10 F552: 85 84 STA m84 ; F554: 29 80 AND #$80 F556: 85 83 STA m83 ; F558: A9 F7 LDA #$F7 ; MSB of tables ... F7xx F55A: 85 B6 STA pf0Graphics+1 ; For PF0 pointer F55C: 85 B8 STA pf1Graphics+1 ; For PF1 pointer F55E: 85 BA STA pf2Graphics+1 ; For PF2 pointer F560: BD CC F7 LDA $F7CC,X ; Lookup LSB F563: 85 10 STA RESP0 ; Set horizontal position of P0 F565: 85 B5 STA pf0Graphics ; LSB for PF0 pointer F567: BD D0 F7 LDA $F7D0,X ; LSB for ... F56A: 85 B7 STA pf1Graphics ; ... PF1 pointer F56C: BD D4 F7 LDA $F7D4,X ; LSB for ... F56F: 85 B9 STA pf2Graphics ; ... PF2 pointer F571: 60 RTS ; Done ; ?? Called from main loop F572: A5 A3 LDA mA3 ; F574: 29 87 AND #$87 F576: 30 02 BMI $F57A ; F578: A9 00 LDA #$00 F57A: 0A ASL A ; Two bytes each F57B: AA TAX F57C: BD 5D F7 LDA plyrNumSize,X ; Number and size of player 0 F57F: 85 04 STA NUSIZ0 ; F581: BD 5E F7 LDA $F75E,X ; Number and size of player 1 F584: 85 05 STA NUSIZ1 ; F586: A5 A3 LDA mA3 ; F588: 29 C0 AND #$C0 F58A: 4A LSR A F58B: 4A LSR A F58C: 4A LSR A F58D: 4A LSR A F58E: A8 TAY F58F: A5 88 LDA m88 ; F591: 8D 82 02 STA SWCHB ; F594: 49 FF EOR #$FF F596: 25 DD AND mDD ; F598: 85 D1 STA mD1 ; F59A: A2 FF LDX #$FF F59C: AD 82 02 LDA SWCHB ; F59F: 29 08 AND #$08 F5A1: D0 04 BNE $F5A7 ; F5A3: A0 10 LDY #$10 F5A5: A2 0F LDX #$0F F5A7: 86 D2 STX scratch1 ; F5A9: A2 03 LDX #$03 F5AB: B9 65 F7 LDA $F765,Y ; F5AE: 45 D1 EOR mD1 ; F5B0: 25 D2 AND scratch1 ; F5B2: 95 06 STA COLUP0,X ; F5B4: 95 D6 STA colorP0,X ; F5B6: 95 D8 STA mD8,X ; F5B8: C8 INY F5B9: CA DEX F5BA: 10 EF BPL $F5AB ; F5BC: 60 RTS ; Clear memory ($A2+X) incrementing X until X=0 ; From F007 X=5D to FF (clear 00 through A2) All registers and variables RAM ; From F16B X=E6 to FF (clear 89 through A2) ; From F1A5 X=DF to FF (clear 82 through A2) F5BD: A9 00 LDA #$00 ; Value 0 F5BF: E8 INX ; Next location F5C0: 95 A2 STA $A2,X ; Clear memory F5C2: D0 FB BNE $F5BF ; All done? F5C4: 60 RTS ; No ... back for more ; -----------------------------------------------------------------------------------------------------------------------------
Data Area
All data from here down
Numbers
F5C5: 0E 0A 0A 0A 0E ; 0 ; .... ***. ; .... *.*. ; .... *.*. ; .... *.*. ; .... **** F5CA: 22 22 22 22 22 ; 11 ; ..*. ..*. ; ..*. ..*. ; ..*. ..*. ; ..*. ..*. ; ..*. ..*. F5CF: EE 22 EE 88 EE ; 22 ; ***. ***. ; ..*. ..*. ; ***. ***. ; *... *... ; ***. ***. F5D4: EE 22 66 22 EE ; 33 ; ***. ***. ; ..*. ..*. ; .**. .**. ; ..*. ..*. ; ***. ***. F5D9: AA AA EE 22 22 ; 44 ; *.*. *.*. ; *.*. *.*. ; ***. ***. ; ..*. ..*. F5DE: EE 88 EE 22 EE ; 55 ; ***. ***. ; *... *... ; ***. ***. ; ..*. ..*. ; ***. ***. F5E3: EE 88 EE AA EE ; 66 ; ***. ***. ; *... *... ; ***. ***. ; *.*. *.*. ; ***. ***. F5E8: EE 22 22 22 22 ; 77 ; ***. ***. ; ..*. ..*. ; ..*. ..*. ; ..*. ..*. ; ..*. ..*. F5ED: EE AA EE AA EE ; 88 ; ***. ***. ; *.*. *.*. ; ***. ***. ; *.*. *.*. ; ***. ***. F5F2: EE AA EE 22 EE ; 99 ; ***. ***. ; *.*. *.*. ; ***. ***. ; ..*. ..*. ; ***. ***. ; ?? From F25E F5F7: F8 F5F8: F7 F5F9: F6 06 F5FB: 06 06 F5FD: 16 17 F5FF: 18 F600: 19 1A 0A F603: 0A F604: 0A F605: FA F606: F9 F8 F7 F609: F6 F6 F60B: 06 16 F60D: 16 17 ; ?? F60F: 18 19 1A 1A 0A FA FA F9 F617: E8 E6 E4 F4 04 14 24 26 F61F: 28 2A 2C 1C 0C FC EC EA F627: C8 C4 C0 E0 00 20 40 44 F62F: 48 4C 4F 2F 0F EF CF CC F637: 00 00 80 80 84 20 88 88 F63F: 92 48 A4 A4 A9 52 AA AA F647: D5 AA DA DA DB 6D EE EE
Tank Pictures
F64F: 00 FC FC 38 3F 38 FC FC F657: 1C 78 FB 7C 1C 1F 3E 18 F65F: 19 3A 7C FF DF 0E 1C 18 F667: 24 64 79 FF FF 4E 0E 04 F66F: 08 08 6B 7F 7F 7F 63 63 F677: 24 26 9E FF FF 72 70 20 F67F: 98 5C 3E FF FB 70 38 18 F687: 38 1E DF 3E 38 F8 7C 18
Jet Pictures
F68F: 60 70 78 FF 78 70 60 00 F697: 00 C1 FE 7C 78 30 30 30 F69F: 00 03 06 FC FC 3C 0C 0C F6A7: 02 04 0C 1C FC FC 1E 06 F6AF: 10 10 10 38 7C FE FE 10 F6B7: 40 20 30 38 3F 3F 78 60 F6BF: 40 60 3F 1F 1E 1E 18 18 F6C7: 00 83 7F 3E 1E 0C 0C 0C
Plane Pictures
F6CF: 00 8E 84 FF FF 04 0E 00
F6D7: 00 0E 04 8F 7F 72 07 00
F6DF: 10 36 2E 0C 1F B2 E0 40
F6E7: 24 2C 5D 1A 1A 30 F0 60
F6EF: 18 5A 7E 5A 18 18 18 78
F6F7: 34 36 5A 78 2C 0C 06 0C
F6FF: 08 6C 70 B8 DC 4E 07 06
F707: 38 10 F0 7C 4F E3 02 00
; ?? From F324 guidance for 0=tanks, 1=jets, 2=planes
F70F: 00 0B 16
; ?? From F32B guides the tanks in pre-game
F712: 00
F713: 10 00
F715: FF
F716: 01 11 ; There are more tank levels than others. is this why there are more in this table??
F718: 01 FF
F71A: 0F
F71B: 1F
F71C: 0F
; ?? guides jets in pre-game
F71D: 50 5F
F71F: 51 FF
F721: 30
F722: 3F
F723: 31 FF
F725: 70 7F
F727: 71 90
F729: B0 70
F72B: FF
F72C: 91 B1
F72E: 71 FF
F730: 9F
F731: BF
F732: 7F
; ?? From F423
F733: 08 02 02
; ?? From F42A
F736: 02
F737: 03
F738: 08
; ?? From F43E
F739: 1D 05 00
F73C: 00
F73D: 00
F73E: 00
F73F: 00
F740: 00
F741: 00
F742: 00
F743: 00
F744: 00
F745: 00
F746: 00
F747: 1D 1D 16
F74A: 16 0F
F74C: 0F
F74D: 00
F74E: 00
F74F: 00
F750: 00
F751: 00
F752: 00
F753: 00
F754: 00
F755: 00
F756: 12
F757: 10 10
F759: 0C
F75A: 0C
F75B: 07
F75C: 07
plyrNumSize:
; Number/size of players, width of missile
; copies width copies width
F75D: 00 00 ; P0 = 1 1 P1 = 1 1
F75F: 01 01 ; P0 = 2 close 1 P1 = 2 close 1
F761: 00 03 ; P0 = 1 1 P1 = 3 close 1
F763: 27 03 ; P0 = 1 quad 4 P1 = 3 close 1
; ?? Colors from F5AB
F765: EA 3C
F767: 82
F768: 44
F769: 32
F76A: 2C 8A DA
F76D: 80
F76E: 9C
F76F: DA
F770: 3A
F771: 64
F772: A8
F773: DA
F774: 4A
F775: 08 04 00 0E
; There are 4 play field patterns
; - Empty tank field
; - Simple tank field
; - Complex tank field
; - Clouds
; The empty-air-field is just no playfield at all
; Each pattern has three tables of 12 bytes. Each pattern is used over 8 rows.
; 12*2*8 = 192 rows of the playfield
; 12 bytes each mirrored left, right, top, bottom
; PF0 for all tank levels
F779: F0 10 10 10 10 10 10 10 10 10 10 10
; PF1 for complex tanks
F785: FF 00 00 00 38 00 00 00 60 20 20 23
; PF2 for complex tanks
F791: FF 80 80 00 00 00 1C 04 00 00 00 00
; PF1 and PF2 for blank tanks (vertical line)
F79D: FF
; PF0 for air (all off)
F79E: 00 00 00
; PF1 and PF2 for air
F7A1: 00 00 00 00 00 00 00 00 00 07 1F 3F
; If you start the clouds PF1 and PF2 at F7A2 then this makes a fatter cloud!
; You could also back up for smaller clouds. I bet the larger cloud was
; intended for a second air playfield ... different for planes and jets.
; Maybe they ran out of code space to use it.
F7AD: 7F
; PF1 for simple tanks
F7AE: FF 00 00 00 00 00 00 00 00 60 20 21
; PF2 for simple tanks
F7BA: FF 00 00 00 80 80 80 80 00 00 00 07
; Pointers to player pictures 0=tank, 1=jet, 2=plane
PlayerPicLSB:
F7C6: 4F CF 8F ; Picture pointers LSB
PlayerPicMSB:
F7C9: F6 F6 F6 ; Picture pointers MSB
; Four different play fields
; F779, F785, F791 ' Complex tanks
; F779, F79D, F79D ' Blank tanks
; F779, F7AE, F7BA ' Simple tanks
; F79E, F7A1, F7A1 ' Clouds
; 0 1 2 3
F7CC: 75 75 75 9A ; PF0 LSB (add 4 the drawing loop treats this as entries 4 through 16 (1)
F7D0: 81 99 AA 9D ; PF1 LSB (add 4)
F7D4: 8D 99 B6 9D ; PF2 LSB (add 4)
Playfields
; ?? From F1AE
F7D8: 24 28
F7DA: 08
F7DB: 20 00 48
F7DE: 40
F7DF: 54
F7E0: 58
F7E1: 25 29
F7E3: 49 55
F7E5: 59 A8 88
F7E8: 98
F7E9: 90 A1
F7EB: 83
F7EC: E8
F7ED: C8
F7EE: E0 C0
F7F0: E9 E2
F7F2: C1 FF
F7F4: 00 00 00 00 00 00
Vectors
F7FA: 00 00 ; NMI Vector (not used)
F7FC: 00 F0 ; Reset vector to F000
F7FE: 0F 11 ; IRQ/vector to 110F (maybe debug hardware?)