andrew/nesgame
Archived
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
This repository has been archived on 2026-05-18. You can view files and clone it. You cannot open issues or pull requests or push a commit.
Files
master
nesgame/nesgame.S

456 lines
13 KiB
ArmAsm
Raw Permalink Normal View History

Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; All NES ROMs have a 16 byte header that describes how the ROM
;; works; specifically, how many banks of 16kB PRG (program) code,
;; how many 8kB banks of CHR data, which mapper to use for bank swapping
;; and how to perform background mirroring
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
;; iNES header block
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.byte "NES",$1A
.byte $01 ;; 1 PRG ROM page (how big is an ophis page?)
.byte $02 ;; 1 CHR (tile/sprite) ROM page (how big is a page?)
.byte $00 ; Horizontal mirroring
.byte $00 ; Mapper 0 (NROM, no bank switching)
.byte $00,$00,$00,$00 ; Reserved bytes
.byte $00,$00,$00,$00 ; Reserved bytes
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.require "include/defines.S"
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
Made oamInsertMultiSprite a real function, just needs a list of actors to stop using $0200 now
2012-11-04 13:25:11 -05:00
.text zp
.org $0000
;; $0000 is reserved for things we use to extend PL/PH for call/return stacks
;; FIXME: Will need to expand this stuff once I start calling 2+
;; functions at once; e.g., JSR a -> JSR b -> JSR c...
;; will need to expand it to a real stack.
.space prevReturnAddrLo 1
.space prevReturnAddrHi 1
.org $0010
;; $0010 - 001F is reserved for global pointers
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.space curPaletteLo 1
.space curPaletteHi 1
Milestone 11 hit very early, 2nd sprite on screen, on my way to a multisprite list that just gets iterated.
2012-11-04 14:41:36 -05:00
.space curSpriteOAMIndexLo 1
.space curSpriteOAMIndexHi 1
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.space curBackgroundLo 1
.space curBackgroundHi 1
.space curBackgroundAttrLo 1
.space curBackgroundAttrHi 1
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.space curSpriteDataLo 1
.space curSpriteDataHi 1
Made oamInsertMultiSprite a real function, just needs a list of actors to stop using $0200 now
2012-11-04 13:25:11 -05:00
.org $0020
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
;; $0020 - 00FF is space for general purpose global variable
.space curBackgroundLen 1
.space curBackgroundAttrLen 1
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.space curSpriteLen 1
.space playery 1
.space playerx 1
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
.space pad1state 1
.space pad2state 1
.space pad3state 1
.space pad4state 1
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.space tempdivident 1
.space tempdivisor 1
.space tempdivresult 1
.space tempdivmodulus 1
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
.org $0040
.space sprMario2DataHook1 1
.space sprMario2DataHook2 1
.space sprMario2DataHook3 1
.space sprMario2DataHook4 1
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.text
.org $C000 ;; PRG bank code starts at 0xC000
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.require "include/math.S"
.require "include/graphics.S"
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; START will be called by the NES whenever the system boots
;; or when the reset button is pressed (think of _start in libc )
;; but the fact that the NES looks at "START" is only because we
;; specified it in bank 1 at 0xFFFA, the vector table
START:
SEI ;; disable IRQs (we don't have an IRQ vector)
CLD ;; disable decimal mode (NES 6502 doesn't have
;; a decimal mode, please don't produce decimal
;; mode instructions, NESASM!)
LDX #$40 ;; load 0x40 into X register
STX $4017 ;; store what's in X to address 0x4017 ...
;; 0x4017 is the Joystick 2 port?! WTF does this
;; do?!
LDX #$FF
TXS ;; Move the contents of X to the stack pointer
INX ;; increment X by 1, which causes overflow, so
;; now X is 0
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
STX $2000 ;; set PPU flag to disable NMI (0x2000 = 0)
Refinements to Milestone 3 implementation ; still not ready to break it out into a subroutine, but is getting much closer. Changed the way the metasprites are packed.
2012-11-03 21:17:39 -04:00
STX $2001 ;; set PPU flag to disable rendering (0x2001=0)
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
STX $4010 ;; disable APU IRQs, no audio
_START_vblankwait:
BIT $2002 ;; Bitwise AND the accumulator (LDA) with mem
Refinements to Milestone 3 implementation ; still not ready to break it out into a subroutine, but is getting much closer. Changed the way the metasprites are packed.
2012-11-03 21:17:39 -04:00
;; at 0x2002, and set the Zero, Sign & Overflow
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; flags accordingly. 0x2002 is the PPU status
;; register; when 0x2002 has bit 7 set, we are
;; in vblank, so this is how we check for it.
BPL _START_vblankwait ;; Until the sign bit is set, loop here. Wait
;; for vblank.
_START_clearmem:
;; Hey look, it's the longest memset() ever!
LDA #$00
STA $0000, x ;; store 0 to (LDX) + 0x0000 ... but X should
;; be 0 at this point (see START where we INX),
;; so why aren't we just using zero-page
;; addressing?
;; ... that's what I thought at first, before
STA $0100, x ;; I realized that I'm looking at a loop:
Milestone 3, though the routine that moves teh sprite to playerx/playery doesn't seem to be working. Still meets the milestone.
2012-11-03 12:03:46 -04:00
STA $0200, x
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
STA $0400, x ;; for ( x = 0; x < 256 ; x++)
STA $0500, x ;; *(0x0100 + x) = 0;
STA $0600, x ;; ....
STA $0700, x ;; the INX and BNE at the bottom are the "; x++)"
Milestone 2
2012-11-03 08:41:02 -04:00
;; This clears the zero page (0000-00FF, the
;; stack (0100-01FF), the entirety of main RAM
;; (0200-07FF)
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
LDA #$FE ;; These two are clearing all of the sprite
Milestone 3 - the _MAIN_*Mario* code works better than it did now, but it still freaks out and cascades the tiles across the screen if I put it into the main loop.
2012-11-03 12:46:27 -04:00
STA $0200, x ;; OAM; previous tutorial had this at 0300,
Milestone 3, though the routine that moves teh sprite to playerx/playery doesn't seem to be working. Still meets the milestone.
2012-11-03 12:03:46 -04:00
;; which may have been wrong. We don't HAVE
;; to reserve this range for OAM; we could
;; just manually poke bits into the PPU, but
;; that is 3-4x (or more) slower than reserving
;; 256 bytes for an OAM copy that we DMA into
;; the PPU on every vblank/NMI
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
INX ;; X is already 0 so this should do X=1,
;; and the Zero and Sign flags should both go 0
BNE _START_clearmem ;; "; x++)", loop back to clrmem until X rolls
_START_vblankwait2:
BIT $2002 ;; copy paste going to happen in ASM
BPL _START_vblankwait2 ;; once we've gotten 1 vblank,
;; cleared mem, and gotten another vblank,
;; the PPU is ready. Wait for it.
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
JMP main
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
main:
;; horray, here is main()
LDA #$00
PHA
LDA #<palette
PHA
LDA #>palette
PHA
JSR paletteLoad
Milestone 2
2012-11-03 08:41:02 -04:00
;; $2000 is the PPU Control register, controlled by various bitflags.
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
;;
Milestone 2
2012-11-03 08:41:02 -04:00
;; 7654 3210
;; |||| ||||
;; |||| ||++- Base nametable address
;; |||| || (0 = $2000; 1 = $2400; 2 = $2800; 3 = $2C00)
;; |||| |+--- VRAM address increment per CPU read/write of PPUDATA
;; |||| | (0: increment by 1, going across;
;; |||| | 1: increment by 32, going down)
;; |||| +---- Sprite pattern table address for 8x8 sprites
;; |||| (0: $0000; 1: $1000; ignored in 8x16 mode)
;; |||+------ Background pattern table address (0: $0000; 1: $1000)
;; ||+------- Sprite size (0: 8x8; 1: 8x16)
;; |+-------- PPU master/slave select (has no effect on the NES)
;; +--------- Generate an NMI at the start of the
;; vertical blanking interval (0: off; 1: on)
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; The PPU mask is set at $2001, the 2nd PPU Control register, and it
;; sets one config option for every bit of the byte
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
;;
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; 76543210
;; ||||||||
;; |||||||+- Grayscale (0: normal color; 1: AND all palette entries
;; ||||||| with 0x30, effectively producing a monochrome display;
;; ||||||| note that colour emphasis STILL works when this is on!)
;; ||||||+-- Disable background clipping in leftmost 8 pixels of screen
;; |||||+--- Disable sprite clipping in leftmost 8 pixels of screen
;; ||||+---- Enable background rendering
;; |||+----- Enable sprite rendering
;; ||+------ Intensify reds (and darken other colors)
;; |+------- Intensify greens (and darken other colors)
;; +-------- Intensify blues (and darken other colors)
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
Milestone 3 : Refined the CopyMarioToORAM routine and moved it inside of the NMI, now it works as designed. Also refactored the 'actor' data that drives the function; See sprMario, sprMario_x, sprMario_y. Now to draw a character all I need is this routine, and 3 arrays; one with tile indexes, and one each of x and y offsets for each of those tiles. Then I can draw the entire thing in the right way given an X,Y starting point.
2012-11-03 16:45:38 -04:00
LDA #$80
STA playerx
STA playery
Made oamInsertMultiSprite a real function, just needs a list of actors to stop using $0200 now
2012-11-04 13:25:11 -05:00
;; Put mario in as the first multisprite
LDA #<sprMarioData
PHA
LDA #>sprMarioData
PHA
LDA sprMario
PHA
;; DO IT
Milestone 11 hit very early, 2nd sprite on screen, on my way to a multisprite list that just gets iterated.
2012-11-04 14:41:36 -05:00
LDA #$00
STA curSpriteOAMIndexLo
LDA #$02
STA curSpriteOAMIndexHi
Made oamInsertMultiSprite a real function, just needs a list of actors to stop using $0200 now
2012-11-04 13:25:11 -05:00
JSR oamInsertMultiSprite
Milestone 11 hit very early, 2nd sprite on screen, on my way to a multisprite list that just gets iterated.
2012-11-04 14:41:36 -05:00
;; ----------------------------------
LDA #$20
STA playerx
LDA #$20
STA playery
LDA #<sprMario2Data
PHA
LDA #>sprMario2Data
PHA
LDA sprMario2
PHA
LDA #$40
STA curSpriteOAMIndexLo
LDA #$02
STA curSpriteOAMIndexHi
JSR oamInsertMultiSprite
;; ---------------------------
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
_bgcall:
LDA bgattrsize
PHA
LDA #>backgroundattrs
PHA
LDA #<backgroundattrs
PHA
LDA bgsize
PHA
LDA #>background
PHA
LDA #<background
PHA
JSR backgroundLoad
;; Apparently you do NOT set sprite and tile data while these are turned on, bad things
;; will happen!
LDA #%10010000 ; enable NMI (so we get a function call every
; vblank), and draw sprites from table 0
STA $2000
LDA #%10011110 ;; turn on sprites, turn on background, don't clip on the left
STA $2001 ;; Write to PPU Control Register 2
LDA #$00 ; hey PPU, stop friggin scrolling!
STA $2005
STA $2005
LDX #$0
Milestone 11 hit very early, 2nd sprite on screen, on my way to a multisprite list that just gets iterated.
2012-11-04 14:41:36 -05:00
Milestone 3 - the _MAIN_*Mario* code works better than it did now, but it still freaks out and cascades the tiles across the screen if I put it into the main loop.
2012-11-03 12:46:27 -04:00
_MAIN_loop:
Milestone 3, though the routine that moves teh sprite to playerx/playery doesn't seem to be working. Still meets the milestone.
2012-11-03 12:03:46 -04:00
JMP _MAIN_loop ;; Loop forever
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
NMI:
Milestone 2
2012-11-03 08:41:02 -04:00
;; We need to copy all our OAM data to put sprites on screen during
;; vblank. $2003 is the PPU OAM address, so we're going to tell it
;; to pull OAM from $0200, and do a DMA transfer.
LDA #$00
STA $2003
Milestone 3 - the _MAIN_*Mario* code works better than it did now, but it still freaks out and cascades the tiles across the screen if I put it into the main loop.
2012-11-03 12:46:27 -04:00
LDA #$02
Milestone 2
2012-11-03 08:41:02 -04:00
STA $4014 ; 4014 is the OAM_DMA operation, which will
; do a DMA from the (LDA|$2003) address,
; for FF bytes (in our case $0200-$02FF),
; which takes ~513 cycles. An unrolled
; loop to do the same thing would take
; 3-4 times as long.
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
_latch1:
LDA #$01
STA $4016
LDA #$00
STA $4016
LDA #$00
STA pad1state
LDX #$08
CLC
_readpad1:
LDA $4016
AND #%00000001
ORA pad1state
DEX
BEQ _storepad1
CLC
ROL
STA pad1state
JMP _readpad1
_storepad1:
STA pad1state
_checkselect:
LDA #padselect
AND pad1state
BEQ _checkstart
LDA sprMario2DataHook1
CLC
ADC #$01
STA sprMario2DataHook1
_checkstart:
LDA #padstart
AND pad1state
BEQ _checka
LDA sprMario2DataHook2
CLC
ADC #$01
STA sprMario2DataHook2
_checka:
LDA #pada
AND pad1state
BEQ _checkb
LDA sprMario2DataHook3
CLC
ADC #$01
STA sprMario2DataHook3
_checkb:
LDA #padb
AND pad1state
BEQ _checkwalkright
LDA sprMario2DataHook4
CLC
ADC #$01
STA sprMario2DataHook4
_checkwalkright:
LDA #%00000001
AND pad1state
BEQ _checkwalkleft
LDA playerx
CLC
ADC #$01
STA playerx
_checkwalkleft:
LDA #padleft
AND pad1state
BEQ _checkwalkup
LDA playerx
SEC
SBC #$01
STA playerx
_checkwalkup:
LDA #padup
AND pad1state
BEQ _checkwalkdown
LDA playery
SEC
SBC #$01
STA playery
_checkwalkdown:
LDA #paddown
AND pad1state
BEQ _move_mario
LDA playery
CLC
ADC #$01
STA playery
_move_mario:
;; Put mario in as the first multisprite
LDA #<sprMarioData
PHA
LDA #>sprMarioData
PHA
LDA sprMario
PHA
;; DO IT
LDA #$00
STA curSpriteOAMIndexLo
LDA #$02
STA curSpriteOAMIndexHi
JSR oamInsertMultiSprite
_nmi_finish:
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
LDA #%10010000 ; enable NMI (so we get a function call every
; vblank), and draw sprites from table 0
STA $2000
LDA #%00011110 ;; turn on sprites, turn on background, don't clip on the left
STA $2001 ;; Write to PPU Control Register 2
LDA #$00 ; hey PPU, stop friggin scrolling!
STA $2005
STA $2005
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
RTI
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
Milestone 2
2012-11-03 08:41:02 -04:00
palette:
Milestone 3.5, tiles and sprites both present on the screen. Also started breaking the code out into libraries for easier editing and maintenance.
2012-11-06 23:30:20 -05:00
.byte $22,$29,$1A,$0F,$22,$36,$17,$0F,$22,$30,$21,$0F,$22,$27,$17,$0F ;;background palette
.byte $22,$1C,$15,$14,$22,$02,$38,$3C,$22,$1C,$15,$14,$22,$02,$38,$3C ;;sprite palette
bgsize:
.byte $80
bgattrsize:
.byte $08
background:
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24 ;;row 1
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24 ;;all sky
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24 ;;row 2
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24 ;;all sky
.byte $24,$24,$24,$24,$45,$45,$24,$24,$45,$45,$45,$45,$45,$45,$24,$24 ;;row 3
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$53,$54,$24,$24 ;;some brick tops
.byte $24,$24,$24,$24,$47,$47,$24,$24,$47,$47,$47,$47,$47,$47,$24,$24 ;;row 4
.byte $24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$24,$55,$56,$24,$24 ;;brick bottoms
backgroundattrs:
.byte %00000000,%00010000,%01010000,%00010000
.byte %00000000,%00000000,%00000000,%00110000
.byte $24,$24,$24,$24
.byte $47,$47,$24,$24
.byte $47,$47,$47,$47
.byte $47,$47,$24,$24
.byte $24,$24,$24,$24
.byte $24,$24,$24,$24
.byte $24,$24,$24,$24
.byte $55,$56,$24,$24 ;;brick bottoms
;; All sprites live between 0200-02FF; there are a max of 64 sprites
;; on screen, and each one has a 4 byte struct describing it.
;; *(sprite + 0) = y position
;; *(sprite + 1) = tile index (0-FF) in the pattern table for pixels
;; *(sprite + 2) = attributes. Color palette, priority, and mirroring.
;; 76543210
;; ||| ||
;; ||| ++- Color Palette of sprite. Choose which set of 4 from
;; ||| the 16 colors to use. You can select sprite colors only
;; ||| in groups of 4 on 4 byte boundaries; so you can select
;; ||| colors 0-3, 4-7, 8-11, and 12-15, but not 2-5, for
;; ||| example. Palette construction and use is an art in
;; ||| itself!
;; |||
;; ||+------ Priority (0: in front of background; 1: behind background)
;; |+------- Flip sprite horizontally
;; +-------- Flip sprite vertically
;; *(sprite + 3) = x position
Milestone 3, though the routine that moves teh sprite to playerx/playery doesn't seem to be working. Still meets the milestone.
2012-11-03 12:03:46 -04:00
sprMario:
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.byte $08 ; Total number of subsprites in this metasprite
Refinements to Milestone 3 implementation ; still not ready to break it out into a subroutine, but is getting much closer. Changed the way the metasprites are packed.
2012-11-03 21:17:39 -04:00
sprMarioData:
;; Y, Tile, Atr, X
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.byte $00,$00,$00,$00
.byte $00,$01,$00,$08
.byte $08,$02,$00,$00
.byte $08,$03,$00,$08
.byte $10,$04,$00,$00
.byte $10,$05,$00,$08
.byte $18,$06,$00,$00
.byte $18,$07,$00,$08
Milestone 11 hit very early, 2nd sprite on screen, on my way to a multisprite list that just gets iterated.
2012-11-04 14:41:36 -05:00
sprMario2:
.byte $08 ; Total number of subsprites in this metasprite
sprMario2Data:
;; Y, Tile, Atr, X
.byte $00,$08,$00,$00
.byte $00,$09,$00,$08
.byte $08,$0A,$00,$00
.byte $08,$0B,$00,$08
.byte $10,$0C,$00,$00
.byte $10,$0D,$00,$08
.byte $18,$0E,$00,$00
.byte $18,$0F,$00,$08
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.advance $FFFA
.word NMI ;; For Non-Maskable Interrupts, please jump to the location
Some reformatting
2012-11-02 22:23:15 -04:00
;; of the NMI label
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.word START ;; For the reset button or power-on, jump to the location
Some reformatting
2012-11-02 22:23:15 -04:00
;; of the START label
Converted to Ophis, ripped out pad reading code to start over
2012-11-04 12:00:03 -05:00
.word 0 ;; If we used an external IRQ vector, we would put it here
Milestone 1 : Boot a rom that does nothing
2012-11-02 22:17:59 -04:00
;; --- graphics bank
Milestone 5 achieved! Mario moves on the screen now in response to the arrow keys, and sets a bunch of variables in response to A/B/Select/Start.
2012-11-11 16:02:54 -05:00
Some reformatting
2012-11-02 22:23:15 -04:00
.org $0000 ;; CHR data is below PRG data in the memory
Milestone 3, though the routine that moves teh sprite to playerx/playery doesn't seem to be working. Still meets the milestone.
2012-11-03 12:03:46 -04:00
.incbin "mario.chr" ; include 8kB of graphics from SMB1
Reference in New Issue Copy Permalink