mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-12-23 03:29:39 +00:00
322 lines
6.5 KiB
NASM
322 lines
6.5 KiB
NASM
|
|
.include "hvsync_generator.v"
|
|
.include "font_cp437_8x8.v"
|
|
.include "ram.v"
|
|
.include "tile_renderer.v"
|
|
.include "sprite_scanline_renderer.v"
|
|
.include "lfsr.v"
|
|
.include "sound_generator.v"
|
|
.include "cpu16.v"
|
|
.include "cpu_platform.v"
|
|
.module cpu_platform
|
|
|
|
.arch femto16
|
|
.org 0x8000
|
|
.len 32768
|
|
|
|
.define RegSwitches $fffe
|
|
.define RegFlags $ffff
|
|
|
|
.define KeyP1Left 1
|
|
.define KeyP1Right 2
|
|
.define KeyP1Up 4
|
|
.define KeyP1Down 8
|
|
.define KeyP1Btn1 16
|
|
.define KeyP1Btn2 32
|
|
|
|
.define ScreenBuffer $6000
|
|
.define PageTable $7e00
|
|
.define SpriteTable $7f00
|
|
|
|
jmp Start
|
|
|
|
Start:
|
|
mov sp,@$6fff
|
|
mov fx,@InitPageTable
|
|
jsr fx
|
|
mov ax,@$0700
|
|
mov fx,@ClearTiles
|
|
jsr fx
|
|
mov fx,@DrawMaze
|
|
jsr fx
|
|
mov bx,@HelloWorld
|
|
mov cx,@$0200
|
|
mov dx,@$6001
|
|
mov fx,@WriteString
|
|
jsr fx
|
|
mov fx,@ClearSprites
|
|
jsr fx
|
|
mov fx,@InitSprites
|
|
jsr fx
|
|
GameLoop:
|
|
mov fx,@WaitVSync
|
|
jsr fx
|
|
mov fx,@MoveSprites
|
|
jsr fx
|
|
jmp GameLoop
|
|
|
|
WaitVSync:
|
|
mov bx,@$FFFF
|
|
mov ax,[bx]
|
|
and ax,#16
|
|
bz WaitVSync
|
|
rts
|
|
|
|
WriteString:
|
|
mov ax,[bx]
|
|
bz StringDone
|
|
xor ax,cx
|
|
mov [dx],ax
|
|
inc bx
|
|
inc dx
|
|
jmp WriteString
|
|
StringDone:
|
|
rts
|
|
|
|
DrawMaze:
|
|
mov dx,@$6080
|
|
mov bx,@MazeData
|
|
DrawMazeLoop:
|
|
mov ax,[bx]
|
|
inc bx
|
|
mov fx,#4
|
|
ShiftMazeChar:
|
|
; rotate high 4 bits to low 4 bits
|
|
asl ax
|
|
rol ax
|
|
rol ax
|
|
rol ax
|
|
mov ex,ax
|
|
and ax,#7
|
|
adc ax,ex
|
|
; lookup character in table
|
|
mov ex,ax
|
|
and ex,#$f
|
|
add ex,@MazeChars
|
|
mov ex,[ex]
|
|
; store to video buffer
|
|
mov [dx],ex
|
|
inc dx
|
|
dec fx
|
|
bnz ShiftMazeChar
|
|
mov ax,dx
|
|
sub ax,@$6380
|
|
bnz DrawMazeLoop
|
|
rts
|
|
|
|
InitPageTable:
|
|
mov ax,@ScreenBuffer ; screen buffer
|
|
mov bx,@PageTable ; page table start
|
|
mov cx,#32 ; 32 rows
|
|
InitPTLoop:
|
|
mov [bx],ax
|
|
add ax,#32
|
|
inc bx
|
|
dec cx
|
|
bnz InitPTLoop
|
|
rts
|
|
ClearTiles:
|
|
mov bx,@ScreenBuffer
|
|
mov cx,@$3c0
|
|
ClearLoop:
|
|
mov [bx],ax
|
|
inc bx
|
|
dec cx
|
|
bnz ClearLoop
|
|
rts
|
|
ClearSprites:
|
|
mov ax,#0
|
|
mov cx,#$40
|
|
mov dx,@SpriteTable
|
|
ClearSLoop:
|
|
mov [dx],ax
|
|
inc dx
|
|
dec cx
|
|
bnz ClearSLoop
|
|
rts
|
|
InitSprites:
|
|
mov bx,@SpriteInitData
|
|
mov cx,#10
|
|
mov dx,@SpriteTable
|
|
InitSLoop:
|
|
mov ax,[bx]
|
|
mov [dx],ax
|
|
inc bx
|
|
inc dx
|
|
dec cx
|
|
bnz InitSLoop
|
|
rts
|
|
MoveSprites:
|
|
mov dx,@SpriteTable
|
|
mov cx,#5
|
|
MoveSLoop:
|
|
mov fx,@MoveSprite
|
|
jsr fx
|
|
add dx,#2
|
|
dec cx
|
|
bnz MoveSLoop
|
|
rts
|
|
MoveSprite:
|
|
; get sprite position
|
|
mov ax,[dx] ; x/y pos
|
|
; get direction sprite is moving
|
|
mov bx,[dx+1] ; direction
|
|
rol bx
|
|
rol bx
|
|
rol bx
|
|
rol bx
|
|
rol bx
|
|
and bx,#3 ; bx = direction (0-3)
|
|
; is sprite in middle of a lane?
|
|
mov ex,ax
|
|
and ex,@$0707
|
|
sub ex,@$0404
|
|
bnz JustUpdatePos ; no, just move
|
|
; is this the player?
|
|
mov fx,dx
|
|
sub fx,@SpriteTable
|
|
bnz NotPlayerMove
|
|
mov fx,@MovePlayer
|
|
jsr fx
|
|
NotPlayerMove:
|
|
; make sure we don't collide with wall
|
|
mov ex,ax
|
|
lsr ex
|
|
lsr ex
|
|
lsr ex ; divide X by 8
|
|
and ex,#31
|
|
mov fx,ex ; fx = X/8
|
|
mov ex,ax
|
|
lsr ex
|
|
lsr ex
|
|
lsr ex
|
|
lsr ex
|
|
lsr ex
|
|
lsr ex ; ex = Y/64
|
|
and ex,@$ffe0
|
|
or ex,fx ; ex = screen offset
|
|
add bx,@DirectionCells
|
|
add ex,[bx] ; add direction offset
|
|
sub bx,@DirectionCells
|
|
add ex,#33 ; add +1 right and +1 down
|
|
add ex,@ScreenBuffer
|
|
mov fx,[ex]
|
|
and fx,@$ff00
|
|
xor fx,@$0500
|
|
bz ChooseNewDirection
|
|
mov fx,#0
|
|
mov [ex],fx ; eat dots
|
|
JustUpdatePos:
|
|
; update x/y position
|
|
add bx,@DirectionXY
|
|
add ax,[bx] ; lookup & add to x/y
|
|
mov [dx],ax ; store x/y pos
|
|
rts
|
|
; Choose a new direction
|
|
ChooseNewDirection:
|
|
mov fx,dx
|
|
sub fx,@SpriteTable
|
|
bnz NotPlayer
|
|
rts
|
|
NotPlayer:
|
|
inc dx
|
|
mov bx,[dx] ; direction
|
|
add bx,@$1000
|
|
mov [dx],bx
|
|
dec dx
|
|
rts
|
|
MovePlayer:
|
|
mov fx,@RegSwitches
|
|
mov fx,[fx]
|
|
SwitchLoop:
|
|
mov ex,#0
|
|
lsr fx
|
|
bcs PlyrMove
|
|
mov ex,#2
|
|
lsr fx
|
|
bcs PlyrMove
|
|
mov ex,#3
|
|
lsr fx
|
|
bcs PlyrMove
|
|
mov ex,#1
|
|
lsr fx
|
|
bcs PlyrMove
|
|
rts
|
|
PlyrMove:
|
|
mov bx,ex
|
|
mov fx,bx
|
|
lsr fx
|
|
ror fx
|
|
ror fx
|
|
ror fx
|
|
ror fx
|
|
inc dx
|
|
mov ex,[dx] ; direction
|
|
and ex,@$0fff
|
|
or ex,fx
|
|
mov [dx],ex
|
|
dec dx
|
|
rts
|
|
|
|
HelloWorld:
|
|
.string HELLO WORLD
|
|
.data 0
|
|
|
|
SpriteInitData:
|
|
.data $b474 $0033
|
|
.data $8464 $0056
|
|
.data $8474 $1067
|
|
.data $8484 $2078
|
|
.data $8474 $3034
|
|
|
|
DirectionXY:
|
|
.data -1
|
|
.data 256
|
|
.data 1
|
|
.data -256
|
|
|
|
DirectionCells:
|
|
.data -1
|
|
.data 32
|
|
.data 1
|
|
.data -32
|
|
|
|
MazeData:
|
|
.data $3111 $1111 $1111 $1114 $3111 $1111 $1111 $1114
|
|
.data $2000 $0000 $0000 $0002 $2000 $0000 $0000 $0002
|
|
.data $2031 $1114 $0311 $1402 $2031 $1140 $3111 $1402
|
|
.data $2d51 $1116 $0511 $1605 $6051 $1160 $5111 $16d2
|
|
.data $2000 $0000 $0000 $0000 $0000 $0000 $0000 $0002
|
|
.data $2031 $1114 $0340 $3111 $1114 $0340 $3111 $1402
|
|
.data $2051 $1116 $0220 $5114 $3116 $0220 $5111 $1602
|
|
.data $2000 $0000 $0220 $0002 $2000 $0220 $0000 $0002
|
|
.data $5111 $1114 $0251 $1402 $2031 $1620 $3111 $1116
|
|
.data $3111 $1116 $0231 $1605 $6051 $1420 $5111 $1114
|
|
.data $2000 $0000 $0220 $0000 $0000 $0220 $0000 $0002
|
|
.data $2031 $1114 $0220 $3111 $1114 $0220 $3111 $1402
|
|
.data $2051 $1116 $0560 $2ccc $ccc2 $0560 $5111 $1602
|
|
.data $2000 $0000 $0000 $2ccc $ccc2 $0000 $0000 $0002
|
|
.data $5111 $1114 $0340 $2ccc $ccc2 $0340 $3111 $1116
|
|
.data $3111 $1116 $0220 $5111 $1116 $0220 $5111 $1114
|
|
.data $2000 $0000 $0220 $0000 $0000 $0220 $0000 $0002
|
|
.data $2031 $1114 $0251 $1403 $4031 $1620 $3111 $1402
|
|
.data $2051 $1116 $0511 $1605 $6051 $1160 $5111 $1602
|
|
.data $2d00 $0000 $0000 $0000 $0000 $0000 $0000 $00d2
|
|
.data $2031 $1114 $0311 $1403 $4031 $1140 $3111 $1402
|
|
.data $2051 $1116 $0511 $1602 $2051 $1160 $5111 $1602
|
|
.data $2000 $0000 $0000 $0002 $2000 $0000 $0000 $0002
|
|
.data $5111 $1111 $1111 $1116 $5111 $1111 $1111 $1116
|
|
|
|
MazeChars:
|
|
.data $07f9 ; empty
|
|
.data $05c4 $05b3 ; horizvert
|
|
.data $05da $05bf $05c0 $05d9 ; corners
|
|
.data $05c3 $05c1 $05c2 $05b4 ; 3-way
|
|
.data $05c5 ; 4-way
|
|
.data $0720 ; empty (no dot)
|
|
.data $07fe ; power pill
|
|
|
|
.data 123 $123
|
|
.align $10
|
|
|