pokecrystal-board/engine/gfx/dma_transfer.asm

605 lines
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HDMATransferAttrmapAndTilemapToWRAMBank3::
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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decoord 0, 0
ld hl, wScratchTilemap
call PadTilemapForHDMATransfer
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransferToWRAMBank3
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ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransferToWRAMBank3
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ret
HDMATransferTilemapToWRAMBank3::
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
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decoord 0, 0
ld hl, wScratchTilemap
call PadTilemapForHDMATransfer
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransferToWRAMBank3
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ret
HDMATransferAttrmapToWRAMBank3:
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransferToWRAMBank3
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ret
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ReloadMapPart::
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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decoord 0, 0
ld hl, wScratchTilemap
call PadTilemapForHDMATransfer
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call DelayFrame
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di
ldh a, [rVBK]
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push af
ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransfer_Wait127Scanlines_toBGMap
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransfer_Wait127Scanlines_toBGMap
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pop af
ldh [rVBK], a
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ei
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ret
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Mobile_ReloadMapPart:
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ld hl, ReloadMapPart ; useless
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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decoord 0, 0
ld hl, wScratchTilemap
call PadTilemapForHDMATransfer
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call DelayFrame
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di
ldh a, [rVBK]
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push af
ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransfer_NoDI
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransfer_NoDI
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pop af
ldh [rVBK], a
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ei
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ret
; unused
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ld hl, .unreferenced_1040da
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jp CallInSafeGFXMode
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.unreferenced_1040da
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ld a, $1
ldh [rVBK], a
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ld a, BANK(w3_d800)
ldh [rSVBK], a
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ld de, w3_d800
ldh a, [hBGMapAddress + 1]
ldh [rHDMA1], a
ldh a, [hBGMapAddress]
ldh [rHDMA2], a
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ld a, d
ldh [rHDMA3], a
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ld a, e
ldh [rHDMA4], a
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ld a, $23
ldh [hDMATransfer], a
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call WaitDMATransfer
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ret
; unused
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ld hl, .unreferenced_104101
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jp CallInSafeGFXMode
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.unreferenced_104101
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ld a, $1
ldh [rVBK], a
ld a, BANK(w3_d800)
ldh [rSVBK], a
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ld hl, w3_d800
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call HDMATransferToWRAMBank3
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ret
OpenAndCloseMenu_HDMATransferTilemapAndAttrmap::
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; OpenText
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
; Transfer wAttrmap and Tilemap to BGMap
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; Fill vBGAttrs with $00
; Fill vBGTiles with " "
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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decoord 0, 0
ld hl, wScratchTilemap
call PadTilemapForHDMATransfer
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call DelayFrame
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di
ldh a, [rVBK]
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push af
ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransfer_Wait123Scanlines_toBGMap
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransfer_Wait123Scanlines_toBGMap
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pop af
ldh [rVBK], a
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ei
ret
Mobile_OpenAndCloseMenu_HDMATransferTilemapAndAttrmap:
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
; Transfer wAttrmap and Tilemap to BGMap
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; Fill vBGAttrs with $00
; Fill vBGTiles with $ff
decoord 0, 0, wAttrmap
ld hl, wScratchAttrmap
call PadAttrmapForHDMATransfer
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ld c, $ff
decoord 0, 0
ld hl, wScratchTilemap
call PadMapForHDMATransfer
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ld a, $1
ldh [rVBK], a
ld hl, wScratchAttrmap
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call HDMATransfer_Wait127Scanlines_toBGMap
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ld a, $0
ldh [rVBK], a
ld hl, wScratchTilemap
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call HDMATransfer_Wait127Scanlines_toBGMap
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ret
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CallInSafeGFXMode:
ldh a, [hBGMapMode]
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push af
ldh a, [hMapAnims]
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push af
xor a
ldh [hBGMapMode], a
ldh [hMapAnims], a
ldh a, [rSVBK]
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push af
ld a, BANK(wScratchTilemap)
ldh [rSVBK], a
ldh a, [rVBK]
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push af
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call ._hl_
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pop af
ldh [rVBK], a
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pop af
ldh [rSVBK], a
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pop af
ldh [hMapAnims], a
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pop af
ldh [hBGMapMode], a
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ret
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._hl_
jp hl
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HDMATransferToWRAMBank3:
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call _LoadHDMAParameters
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ld a, $23
ldh [hDMATransfer], a
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WaitDMATransfer:
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.loop
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call DelayFrame
ldh a, [hDMATransfer]
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and a
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jr nz, .loop
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ret
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HDMATransfer_Wait127Scanlines_toBGMap:
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; HDMA transfer from hl to [hBGMapAddress]
; hBGMapAddress -> de
; 2 * SCREEN_HEIGHT -> c
ldh a, [hBGMapAddress + 1]
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ld d, a
ldh a, [hBGMapAddress]
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ld e, a
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ld c, 2 * SCREEN_HEIGHT
jr HDMATransfer_Wait127Scanlines
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HDMATransfer_Wait123Scanlines_toBGMap:
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; HDMA transfer from hl to [hBGMapAddress]
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; hBGMapAddress -> de
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; 2 * SCREEN_HEIGHT -> c
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; $7b --> b
ldh a, [hBGMapAddress + 1]
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ld d, a
ldh a, [hBGMapAddress]
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ld e, a
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ld c, 2 * SCREEN_HEIGHT
jr HDMATransfer_Wait123Scanlines
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HDMATransfer_NoDI:
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; HDMA transfer from hl to [hBGMapAddress]
; [hBGMapAddress] --> de
; 2 * SCREEN_HEIGHT --> c
ldh a, [hBGMapAddress + 1]
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ld d, a
ldh a, [hBGMapAddress]
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ld e, a
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ld c, 2 * SCREEN_HEIGHT
; [rHDMA1, rHDMA2] = hl & $fff0
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ld a, h
ldh [rHDMA1], a
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ld a, l
and $f0
ldh [rHDMA2], a
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; [rHDMA3, rHDMA4] = de & $1ff0
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ld a, d
and $1f
ldh [rHDMA3], a
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ld a, e
and $f0
ldh [rHDMA4], a
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; b = c | %10000000
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ld a, c
dec c
or $80
ld b, a
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; d = $7f - c + 1
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ld a, $7f
sub c
ld d, a
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; while [rLY] >= d: pass
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.loop1
ldh a, [rLY]
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cp d
jr nc, .loop1
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; while not [rSTAT] & 3: pass
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.loop2
ldh a, [rSTAT]
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and $3
jr z, .loop2
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; load the 5th byte of HDMA
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ld a, b
ldh [rHDMA5], a
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; wait until rLY advances (c + 1) times
ldh a, [rLY]
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inc c
ld hl, rLY
.loop3
cp [hl]
jr z, .loop3
ld a, [hl]
dec c
jr nz, .loop3
ld hl, rHDMA5
res 7, [hl]
ret
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HDMATransfer_Wait123Scanlines:
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ld b, $7b
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jr _continue_HDMATransfer
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HDMATransfer_Wait127Scanlines:
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ld b, $7f
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_continue_HDMATransfer:
; a lot of waiting around for hardware registers
; [rHDMA1, rHDMA2] = hl & $fff0
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ld a, h
ldh [rHDMA1], a
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ld a, l
and $f0 ; high nybble
ldh [rHDMA2], a
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; [rHDMA3, rHDMA4] = de & $1ff0
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ld a, d
and $1f ; lower 5 bits
ldh [rHDMA3], a
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ld a, e
and $f0 ; high nybble
ldh [rHDMA4], a
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; e = c | %10000000
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ld a, c
dec c
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or $80
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ld e, a
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; d = b - c + 1
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ld a, b
sub c
ld d, a
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; while [rLY] >= d: pass
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.ly_loop
ldh a, [rLY]
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cp d
jr nc, .ly_loop
di
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; while [rSTAT] & 3: pass
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.rstat_loop_1
ldh a, [rSTAT]
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and $3
jr nz, .rstat_loop_1
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; while not [rSTAT] & 3: pass
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.rstat_loop_2
ldh a, [rSTAT]
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and $3
jr z, .rstat_loop_2
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; load the 5th byte of HDMA
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ld a, e
ldh [rHDMA5], a
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; wait until rLY advances (c + 1) times
ldh a, [rLY]
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inc c
ld hl, rLY
.final_ly_loop
cp [hl]
jr z, .final_ly_loop
ld a, [hl]
dec c
jr nz, .final_ly_loop
ld hl, rHDMA5
res 7, [hl]
ei
ret
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_LoadHDMAParameters:
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ld a, h
ldh [rHDMA1], a
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ld a, l
ldh [rHDMA2], a
ldh a, [hBGMapAddress + 1]
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and $1f
ldh [rHDMA3], a
ldh a, [hBGMapAddress]
ldh [rHDMA4], a
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ret
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PadTilemapForHDMATransfer:
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ld c, " "
jr PadMapForHDMATransfer
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PadAttrmapForHDMATransfer:
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ld c, $0
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PadMapForHDMATransfer:
; pad a 20x18 map to 32x18 for HDMA transfer
; back up the padding value in c to hMapObjectIndexBuffer
ldh a, [hMapObjectIndexBuffer]
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push af
ld a, c
ldh [hMapObjectIndexBuffer], a
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; for each row on the screen
ld c, SCREEN_HEIGHT
.loop1
; for each tile in the row
ld b, SCREEN_WIDTH
.loop2
; copy from de to hl
ld a, [de]
inc de
ld [hli], a
dec b
jr nz, .loop2
; load the original padding value of c into hl for 32 - 20 = 12 rows
ldh a, [hMapObjectIndexBuffer]
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ld b, BG_MAP_WIDTH - SCREEN_WIDTH
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.loop3
ld [hli], a
dec b
jr nz, .loop3
dec c
jr nz, .loop1
; restore the original value of hMapObjectIndexBuffer
pop af
ldh [hMapObjectIndexBuffer], a
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ret
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_Get2bpp::
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; 2bpp when [rLCDC] & $80
; switch to WRAM bank 6
ldh a, [rSVBK]
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push af
ld a, BANK(wScratchTilemap)
ldh [rSVBK], a
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push bc
push hl
; Copy c tiles of the 2bpp from b:de to wScratchTilemap
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ld a, b ; bank
ld l, c ; number of tiles
ld h, $0
; multiply by 16 (16 bytes of a 2bpp = 8 x 8 tile)
add hl, hl
add hl, hl
add hl, hl
add hl, hl
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ld b, h
ld c, l
ld h, d ; address
ld l, e
ld de, wScratchTilemap
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call FarCopyBytes
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pop hl
pop bc
push bc
call DelayFrame
pop bc
ld d, h
ld e, l
ld hl, wScratchTilemap
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call HDMATransfer_Wait127Scanlines
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; restore the previous bank
pop af
ldh [rSVBK], a
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ret
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_Get1bpp::
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; 1bpp when [rLCDC] & $80
.loop
ld a, c
cp $10
jp c, .bankswitch
jp z, .bankswitch
push bc
push hl
push de
ld c, $10
call .bankswitch
pop de
ld hl, $80
add hl, de
ld d, h
ld e, l
pop hl
lb bc, 1, 0
add hl, bc
pop bc
ld a, c
sub $10
ld c, a
jr .loop
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.bankswitch
ldh a, [rSVBK]
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push af
ld a, BANK(wScratchTilemap)
ldh [rSVBK], a
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push bc
push hl
ld a, b
ld l, c
ld h, $0
add hl, hl ; multiply by 8
add hl, hl ; multiply by 8
add hl, hl ; multiply by 8
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ld c, l
ld b, h
ld h, d
ld l, e
ld de, wScratchTilemap
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call FarCopyBytesDouble_DoubleBankSwitch
pop hl
pop bc
push bc
call DelayFrame
pop bc
ld d, h
ld e, l
ld hl, wScratchTilemap
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call HDMATransfer_Wait127Scanlines
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pop af
ldh [rSVBK], a
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ret
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HDMATransfer_OnlyTopFourRows:
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ld hl, .Function
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jp CallInSafeGFXMode
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.Function:
ld hl, wScratchTilemap
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decoord 0, 0
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call .Copy
ld hl, wScratchTilemap + $80
decoord 0, 0, wAttrmap
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call .Copy
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ld a, $1
ldh [rVBK], a
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ld c, $8
ld hl, wScratchTilemap + $80
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debgcoord 0, 0, vBGMap1
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call HDMATransfer_Wait127Scanlines
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ld a, $0
ldh [rVBK], a
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ld c, $8
ld hl, wScratchTilemap
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debgcoord 0, 0, vBGMap1
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call HDMATransfer_Wait127Scanlines
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ret
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.Copy:
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ld b, 4
.outer_loop
ld c, SCREEN_WIDTH
.inner_loop
ld a, [de]
ld [hli], a
inc de
dec c
jr nz, .inner_loop
ld a, l
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add BG_MAP_WIDTH - SCREEN_WIDTH
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ld l, a
ld a, h
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adc 0
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ld h, a
dec b
jr nz, .outer_loop
ret