mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-11-25 03:34:05 +00:00
57 lines
1.2 KiB
NASM
57 lines
1.2 KiB
NASM
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.arch femto16
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.include "hvsync_generator.v"
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.include "font_cp437_8x8.v"
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.include "ram.v"
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.include "tile_renderer.v"
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.include "sprite_scanline_renderer.v"
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.include "lfsr.v"
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.include "sound_generator.v"
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.include "cpu16.v"
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.include "cpu_platform.v"
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.module cpu_platform
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.org 0x8000
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.len 1024
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mov sp,@$6fff
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mov dx,@InitPageTable
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jsr dx
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mov ax,@$4ffe
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mov dx,@ClearTiles
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jsr dx
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mov ex,@ClearSprites
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jsr ex
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reset
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InitPageTable:
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mov ax,@$6000 ; screen buffer
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mov bx,@$7e00 ; page table start
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mov cx,#32 ; 32 rows
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InitPTLoop:
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mov [bx],ax
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add ax,#32
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inc bx
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dec cx
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bnz InitPTLoop
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rts
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ClearTiles:
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mov bx,@$6000
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mov cx,@$390
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ClearLoop:
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mov [bx],ax
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inc bx
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dec cx
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bnz ClearLoop
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rts
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ClearSprites:
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mov bx,@$7f00
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mov ax,#0
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mov cx,#$40
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ClearSLoop:
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mov ax,[bx]
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add ax,@$101
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mov [bx],ax
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inc bx
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dec cx
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bnz ClearSLoop
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