163 lines
6.3 KiB
ArmAsm
163 lines
6.3 KiB
ArmAsm
; Global addresses and engine values
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SHADOW_REG equ $E0C035
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STATE_REG equ $E0C068
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NEW_VIDEO_REG equ $E0C029
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BORDER_REG equ $E0C034 ; 0-3 = border, 4-7 Text color
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VBL_VERT_REG equ $E0C02E
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VBL_HORZ_REG equ $E0C02F
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KBD_REG equ $E0C000
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KBD_STROBE_REG equ $E0C010
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VBL_STATE_REG equ $E0C019
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MOD_REG equ $E0C025
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COMMAND_KEY_REG equ $E0C061
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OPTION_KEY_REG equ $E0C062
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SHADOW_SCREEN equ $012000
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SHADOW_SCREEN_SCB equ $019D00
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SHADOW_SCREEN_PALETTES equ $019E00
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SHR_SCREEN equ $E12000
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SHR_SCB equ $E19D00
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SHR_PALETTES equ $E19E00
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; Direct page locations used by the engine
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ScreenHeight equ 0 ; Height of the playfield in scan lines
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ScreenWidth equ 2 ; Width of the playfield in bytes
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ScreenY0 equ 4 ; First vertical line on the physical screen of the playfield
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ScreenY1 equ 6 ; End of playfield on the physical screen. If the height is 20 and Y0 is
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ScreenX0 equ 8 ; 100, then ScreenY1 = 120.
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ScreenX1 equ 10
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ScreenTileHeight equ 12 ; Height of the playfield in 8x8 blocks
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ScreenTileWidth equ 14 ; Width of the playfield in 8x8 blocks
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StartX equ 16 ; Which code buffer byte is the left edge of the screen. Range = 0 to 167
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StartY equ 18 ; Which code buffer line is the top of the screen. Range = 0 to 207
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EngineMode equ 20 ; Defined the mode/capabilities that are enabled
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; bit 0: 0 = Single Background, 1 = Parallax
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DirtyBits equ 22 ; Identify values that have changed between frames
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BG1DataBank equ 24 ; Data bank that holds BG1 layer data
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BG1AltBank equ 26 ; Alternate BG1 bank
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BlitterDP equ 28 ; Direct page address the holder blitter data
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OldStartX equ 30
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OldStartY equ 32
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LastPatchOffset equ 34 ; Offset into code field that was patched with BRA instructions
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StartXMod164 equ 36
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StartYMod208 equ 38
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BG1StartX equ 40 ; Logical offset of the second background
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BG1StartXMod164 equ 42
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BG1StartY equ 44
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BG1StartYMod208 equ 46
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OldBG1StartX equ 48
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OldBG1StartY equ 50
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BG1OffsetIndex equ 52
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BG0TileOriginX equ 54 ; Coordinate in the tile map that corresponds to the top-left corner
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BG0TileOriginY equ 56
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OldBG0TileOriginX equ 58
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OldBG0TileOriginY equ 60
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BG1TileOriginX equ 62 ; Coordinate in the tile map that corresponds to the top-left corner
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BG1TileOriginY equ 64
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OldBG1TileOriginX equ 66
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OldBG1TileOriginY equ 68
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TileMapWidth equ 70
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TileMapHeight equ 72
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TileMapPtr equ 74
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FringeMapPtr equ 78
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BG1TileMapWidth equ 82
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BG1TileMapHeight equ 84
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BG1TileMapPtr equ 86
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SCBArrayPtr equ 90 ; Used for palette binding
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SpriteBanks equ 94 ; Bank bytes for the sprite data and sprite mask
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Next equ 96
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BankLoad equ 128
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AppSpace equ 160 ; 16 bytes of space reserved for application use
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tiletmp equ 178 ; 16 bytes of temp storage for the tile renderers
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blttmp equ 192 ; 32 bytes of local cache/scratch space for blitter
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tmp8 equ 224 ; another 16 bytes of temporary space to be used as scratch
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tmp9 equ 226
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tmp10 equ 228
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tmp11 equ 230
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tmp12 equ 232
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tmp13 equ 234
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tmp14 equ 236
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tmp15 equ 238
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tmp0 equ 240 ; 16 bytes of temporary space to be used as scratch
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tmp1 equ 242
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tmp2 equ 244
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tmp3 equ 246
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tmp4 equ 248
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tmp5 equ 250
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tmp6 equ 252
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tmp7 equ 254
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DIRTY_BIT_BG0_X equ $0001
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DIRTY_BIT_BG0_Y equ $0002
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DIRTY_BIT_BG1_X equ $0004
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DIRTY_BIT_BG1_Y equ $0008
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DIRTY_BIT_BG0_REFRESH equ $0010
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DIRTY_BIT_BG1_REFRESH equ $0020
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; Script definition
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YIELD equ $8000
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JUMP equ $4000
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SET_PALETTE_ENTRY equ $0002
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SWAP_PALETTE_ENTRY equ $0004
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SET_DYN_TILE equ $0006
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CALLBACK equ $0010
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; ReadControl return value bits
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PAD_BUTTON_B equ $01
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PAD_BUTTON_A equ $02
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PAD_KEY_DOWN equ $04
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; Tile constants
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TILE_ID_MASK equ $01FF
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TILE_SPRITE_BIT equ $8000 ; Set if this tile intersects an active sprite
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TILE_PRIORITY_BIT equ $4000 ; Put tile on top of sprite
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TILE_FRINGE_BIT equ $2000
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TILE_MASK_BIT equ $1000
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TILE_DYN_BIT equ $0800
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TILE_VFLIP_BIT equ $0400
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TILE_HFLIP_BIT equ $0200
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; Sprite constants
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SPRITE_HIDE equ $8000
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SPRITE_16X16 equ $1800
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SPRITE_16X8 equ $1000
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SPRITE_8X16 equ $0800
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SPRITE_8X8 equ $0000
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SPRITE_VFLIP equ $0400
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SPRITE_HFLIP equ $0200
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MAX_TILES equ {26*41} ; Number of tiles in the code field (41 columns * 26 rows)
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TILE_STORE_SIZE equ {MAX_TILES*2} ; The tile store contains a tile descriptor in each slot
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TS_TILE_ID equ TILE_STORE_SIZE*0
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TS_DIRTY equ TILE_STORE_SIZE*1
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TS_SPRITE_FLAG equ TILE_STORE_SIZE*2
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TS_TILE_ADDR equ TILE_STORE_SIZE*3 ; const value
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TS_CODE_ADDR_LOW equ TILE_STORE_SIZE*4 ; const value
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TS_CODE_ADDR_HIGH equ TILE_STORE_SIZE*5 ; const value
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TS_WORD_OFFSET equ TILE_STORE_SIZE*6
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TS_BASE_ADDR equ TILE_STORE_SIZE*7
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TS_SPRITE_ADDR equ TILE_STORE_SIZE*8
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TS_SCREEN_ADDR equ TILE_STORE_SIZE*9
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