Notes:Final Fight (SNES)/Bank 00

This is a sub-page of Notes:Final Fight (SNES).

Bank 00

Get Random Number

$00/B0E1 DA          PHX
$00/B0E2 A9 00       LDA #$00
$00/B0E4 EB          XBA
$00/B0E5 AD 09 01    LDA $0109  [$00:0109]
$00/B0E8 1A          INC A
$00/B0E9 29 03       AND #$03
$00/B0EB 8D 09 01    STA $0109  [$00:0109]
$00/B0EE AA          TAX
$00/B0EF BD 0A 01    LDA $010A,x
$00/B0F2 69 13       ADC #$13
$00/B0F4 9D 0A 01    STA $010A,x
$00/B0F7 FA          PLX
$00/B0F8 6B          RTL

Update Random Number Generator

$00/B0F9 AD 0A 01    LDA $010A  [$00:010A]
$00/B0FC 69 01       ADC #$01
$00/B0FE 8D 0A 01    STA $010A  [$00:010A]
$00/B101 AD 0B 01    LDA $010B  [$00:010B]
$00/B104 69 03       ADC #$03
$00/B106 8D 0B 01    STA $010B  [$00:010B]
$00/B109 AD 0C 01    LDA $010C  [$00:010C]
$00/B10C 69 05       ADC #$05
$00/B10E 8D 0C 01    STA $010C  [$00:010C]
$00/B111 AD 0D 01    LDA $010D  [$00:010D]
$00/B114 69 07       ADC #$07
$00/B116 8D 0D 01    STA $010D  [$00:010D]
$00/B119 AD B4 0C    LDA $0CB4  [$00:0CB4]   //Frame counter (load lower 8 bits of 16-bit value)
$00/B11C D0 15       BNE $15    [$B133]      //Skip to $B133 if non-zero. Every 256 frames (approx. 4.27 seconds) the $B11E-$B132 block will execute to provide more randomness
$00/B11E AD 0D 01    LDA $010D  [$00:010D]
$00/B121 6D 0C 01    ADC $010C  [$00:010C]
$00/B124 8D 0C 01    STA $010C  [$00:010C]
$00/B127 6D 0B 01    ADC $010B  [$00:010B]
$00/B12A 8D 0B 01    STA $010B  [$00:010B]
$00/B12D 6D 0A 01    ADC $010A  [$00:010A]
$00/B130 8D 0A 01    STA $010A  [$00:010A]
$00/B133 6B          RTL

Load Random Number When Enemy Spawns

$00/B2A4 E2 10       SEP #$10
$00/B2A6 22 E1 B0 00 JSL $00B0E1[$00:B0E1]   //Get Random Number
$00/B2AA 29 0F       AND #$0F                //Keep only lower 4 bits of random number
$00/B2AC AA          TAX
$00/B2AD BD B5 B2    LDA $B2B5,x             //TODO - unknown table
$00/B2B0 85 66       STA $66
$00/B2B2 C2 10       REP #$10
$00/B2B4 6B          RTL

Controller Copy

$00/CA41 AD CC 00    LDA $00CC  [$00:00CC]   //Demo mode
$00/CA44 F0 3D       BEQ $3D    [$CA83]      //Skip to $CA83 if in demo mode
$00/CA46 A2 00 0D    LDX #$0D00              //Player 1 stats
$00/CA49 A0 10 01    LDY #$0110              //Controller 1 buttons base address
$00/CA4C BD 11 00    LDA $0011,x             //Player 1 controller
$00/CA4F F0 03       BEQ $03    [$CA54]      //Skip to $CA54 if player 1 is using controller 1*
$00/CA51 A0 12 01    LDY #$0112              //Controller 2 buttons base address
$00/CA54 C2 20       REP #$20
$00/CA56 B9 08 00    LDA $0008,y
$00/CA59 9D 64 00    STA $0064,x             //Copy controller button presses
$00/CA5C B9 00 00    LDA $0000,y
$00/CA5F 9D 66 00    STA $0066,x             //Copy controller button presses
$00/CA62 E2 20       SEP #$20
$00/CA64 A2 80 0D    LDX #$0D80              //Player 2 stats
$00/CA67 A0 10 01    LDY #$0110              //Controller 1 buttons base address
$00/CA6A BD 11 00    LDA $0011,x             //Player 2 controller
$00/CA6D F0 03       BEQ $03    [$CA72]      //Skip to $CA72 if player 2 is using controller 1
$00/CA6F A0 12 01    LDY #$0112              //Controller 2 buttons base address
$00/CA72 C2 20       REP #$20
$00/CA74 B9 08 00    LDA $0008,y
$00/CA77 9D 64 00    STA $0064,x             //Copy controller button presses
$00/CA7A B9 00 00    LDA $0000,y
$00/CA7D 9D 66 00    STA $0066,x             //Copy controller button presses
$00/CA80 E2 20       SEP #$20
$00/CA82 6B          RTL

*Use PAR code 00CA5000 to control player 1 using the second controller.  Worth noting that only the first controller can pause the game.

Set Platform Height in Round

$00/D0A6 C2 20       REP #$20
$00/D0A8 AD B0 0C    LDA $0CB0  [$00:0CB0]   //Round
$00/D0AB 29 FF 00    AND #$00FF
$00/D0AE 0A          ASL A
$00/D0AF AA          TAX
$00/D0B0 BF BA D0 00 LDA $00D0BA,x           //Platform height table
$00/D0B4 8D CA 0C    STA $0CCA  [$00:0CCA]
$00/D0B7 E2 20       SEP #$20
$00/D0B9 6B          RTL

Platform Height in Round Table

00D0BA 4000 //Slum
00D0BC 2000 //Subway
00D0BE 4000 //West Side
00D0C0 4000 //Industrial Area
00D0C2 4000 //Bay Area
00D0C4 4000 //Up Town
00D0C6 4000 //Break Car
00D0C8 4000 //Break Glass
00D0CA 4000 //Empty slot
00D0CC 4000 //Empty slot
00D0CE 4000 //Empty slot

TODO 00D16B

$00/D16B AE CA 0C    LDX $0CCA  [$00:0CCA]   //Platform height in stage
$00/D16E 8E CE 0C    STX $0CCE  [$00:0CCE]   //Height of platform/object player is standing next to
$00/D171 22 FF D2 00 JSL $00D2FF[$00:D2FF]

Jump to Tile Properties for Tile Standing on

$00/D3C6 AD 00 00    LDA $0000  [$00:0000]
$00/D3C9 0A          ASL A
$00/D3CA AA          TAX
$00/D3CB FC D4 D3    JSR ($D3D4,x)

Tile Properties Pointer Table

00D3D4 00 22D4
00D3D6 01 22D4
00D3D8 02 26D4
00D3DA 03 39D4
00D3DC 04 4CD4
00D3DE 05 64D4
00D3E0 06 7CD4
00D3E2 07 8FD4
00D3E4 08 B7D4
00D3E6 09 DFD4
00D3E8 0A 95D4
00D3EA 0B BDD4
00D3EC 0C F7D4
00D3EE 0D 13D5
00D3F0 0E 2FD5
00D3F2 0F 4BD5
00D3F4 10 FDD4
00D3F6 11 19D5
00D3F8 12 35D5
00D3FA 13 51D5
00D3FC 14 67D5
00D3FE 15 67D5 (unused)
00D400 16 67D5 (unused)
00D402 17 67D5
00D404 18 67D5
00D406 19 6BD5 (unused)
00D408 1A 9BD4 (unused)
00D40A 1B C3D4 (unused)
00D40C 1C 7ED5
00D40E 1D A1D4
00D410 1E C9D4
00D412 1F 96D5
00D414 20 9AD5
00D416 21 ADD5
00D418 22 C3D5
00D41A 23 D9D5
00D41C 24 DFD5
00D41E 25 F5D5
00D420 26 FBD5

Copy Round Tile Properties from ROM to RAM

$00/E010 C2 20       REP #$20
$00/E012 0B          PHD
$00/E013 8B          PHB
$00/E014 A9 00 00    LDA #$0000
$00/E017 5B          TCD
$00/E018 8D 12 00    STA $0012  [$00:0012]
$00/E01B E2 20       SEP #$20
$00/E01D AD B0 0C    LDA $0CB0  [$00:0CB0]   //Round
$00/E020 0A          ASL A
$00/E021 AA          TAX
$00/E022 BC 69 E0    LDY $E069,x             //Pointer to Tile Properties Set
$00/E025 BB          TYX
$00/E026 BD 00 00    LDA $0000,x
$00/E029 8D 00 00    STA $0000  [$00:0000]   //Number of chunks
$00/E02C E8          INX
$00/E02D 8E 10 00    STX $0010  [$00:0010]   //Store start address of chunk
$00/E030 20 3B E0    JSR $E03B  [$00:E03B]   //Copy 256 Byte Chunk of Round Tile Properties
$00/E033 CE 00 00    DEC $0000  [$00:0000]   //Chunks for Round counter -1
$00/E036 D0 F8       BNE $F8    [$E030]      //Loop until all chunks for Round copied
$00/E038 AB          PLB
$00/E039 2B          PLD
$00/E03A 60          RTS

Copy 256 Byte Chunk of Round Tile Properties

$00/E03B A9 00       LDA #$00
$00/E03D EB          XBA
$00/E03E B2 10       LDA ($10)               //Start address of chunk
$00/E040 EB          XBA
$00/E041 AA          TAX
$00/E042 AC 12 00    LDY $0012  [$00:0012]
$00/E045 C2 20       REP #$20
$00/E047 EE 10 00    INC $0010  [$00:0010]   //Set start address of next chunk for the next time this subroutine runs
$00/E04A E2 20       SEP #$20
$00/E04C 8B          PHB
$00/E04D A9 7F       LDA #$7F                //Destination RAM bank
$00/E04F 48          PHA
$00/E050 AB          PLB
$00/E051 A9 00       LDA #$00
$00/E053 8D 08 00    STA $0008  [$7F:0008]
$00/E056 BF 00 80 0F LDA $0F8000,x[$0F:8000] //Source ROM address
$00/E05A 99 00 20    STA $2000,y[$7F:2000]   //Destination RAM address (+$7F0000)
$00/E05D E8          INX
$00/E05E C8          INY
$00/E05F CE 08 00    DEC $0008  [$7F:0008]
$00/E062 D0 F2       BNE $F2    [$E056]      //Loop until entire 256 byte chunk copied
$00/E064 AB          PLB
$00/E065 8C 12 00    STY $0012  [$00:0012]
$00/E068 60          RTS

Tile Properties Pointer Table

00E069 7FE0 Slum
00E06B B9E0 Subway
00E06D 88E0 West Side
00E06F 95E0 Industrial Area
00E071 95E0 Bay Area
00E073 9AE0 Up Town
00E075 ABE0 Break Car
00E077 ADE0 Break Glass
00E079 B1E0 Unused slot
00E07B B1E0 Unused slot
00E07D B1E0 Unused slot

Tile Properties Sets

The first byte is the number of 256 byte chunks in the set. For the following bytes, to get the start address of the 256 byte chunk, multiply the value by $0100 and add it to the base address of $0F8000.

E07F 08 0001020304050618 - Slum
E088 0C 0008191A1B1C1D1E1F202118 - West Side
E095 04 00060818 - Bay Area (Industrial Area also points here)
E09A 10 00060F1011121314181F222325262728 - Up Town (note that $24 is skipped - the 256 byte chunk is blank, all $00)
E0AB 01 1F - Break Car
E0AD 03 151617 - Break Glass
E0B1 07 00010203040506 (??? - a copy of the Slum, without the final chunk - what's the purpose of this?)
E0B9 0C 00060708090A0B0C0D0E0F18 - Subway

Update Countdown Timer HUD

$00/E59B A9 20       LDA #$20
$00/E59D EB          XBA
$00/E59E AD BD 0C    LDA $0CBD  [$00:0CBD]   //First digit of countdown timer
$00/E5A1 0A          ASL A
$00/E5A2 0A          ASL A
$00/E5A3 09 80       ORA #$80
$00/E5A5 C2 20       REP #$20
$00/E5A7 8F 9C 24 7E STA $7E249C[$7E:249C]   //Update upper left tile
$00/E5AB 1A          INC A
$00/E5AC 8F 9E 24 7E STA $7E249E[$7E:249E]   //Update upper right tile
$00/E5B0 1A          INC A
$00/E5B1 8F DC 24 7E STA $7E24DC[$7E:24DC]   //Update lower left tile
$00/E5B5 1A          INC A
$00/E5B6 8F DE 24 7E STA $7E24DE[$7E:24DE]   //Update lower right tile
$00/E5BA E2 20       SEP #$20
$00/E5BC AD BC 0C    LDA $0CBC  [$00:0CBC]   //Second digit of countdown timer
$00/E5BF 0A          ASL A
$00/E5C0 0A          ASL A
$00/E5C1 09 80       ORA #$80
$00/E5C3 C2 20       REP #$20
$00/E5C5 8F A0 24 7E STA $7E24A0[$7E:24A0]   //Update upper left tile
$00/E5C9 1A          INC A
$00/E5CA 8F A2 24 7E STA $7E24A2[$7E:24A2]   //Update upper right tile
$00/E5CE 1A          INC A
$00/E5CF 8F E0 24 7E STA $7E24E0[$7E:24E0]   //Update lower left tile
$00/E5D3 1A          INC A
$00/E5D4 8F E2 24 7E STA $7E24E2[$7E:24E2]   //Update lower right tile
$00/E5D8 E2 20       SEP #$20
$00/E5DA EE E6 00    INC $00E6  [$00:00E6]
$00/E5DD 6B          RTL

Update Lives HUD

$00/E5DE AD 6F 0D    LDA $0D6F  [$00:0D6F]   //Lives 9 and beyond
$00/E5E1 F0 04       BEQ $04    [$E5E7]      //Skip to $E5E7 if not 9 lives or more remaining
$00/E5E3 A9 09       LDA #$09                //Appears as 8 lives on HUD
$00/E5E5 80 07       BRA $07    [$E5EE]
$00/E5E7 AD 6E 0D    LDA $0D6E  [$00:0D6E]   //Lives
$00/E5EA 3A          DEC A                   //Lives -1
$00/E5EB 10 01       BPL $01    [$E5EE]      //Skip to $E5EE if counter rolls over
$00/E5EC 1A          INC A                   //Restore previous value
$00/E5EE 8F 56 24 7E STA $7E2456[$7E:2456]   //Update lives HUD tilemap
$00/E5F2 EE E6 00    INC $00E6  [$00:00E6]
$00/E5F5 6B          RTL