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; copy c bytes of data from hl to de, b times.
; used to copy gfx data with c = TILE_SIZE
CopyGfxData:
ld a, [wLCDC]
rla
jr nc, .next_tile
.hblank_copy
push bc
push hl
push de
ld b, c
call JPHblankCopyDataHLtoDE
ld b, $0
pop hl
add hl, bc
ld e, l
ld d, h
pop hl
add hl, bc
pop bc
dec b
jr nz, .hblank_copy
ret
.next_tile
push bc
.copy_tile
ld a, [hli]
ld [de], a
inc de
dec c
jr nz, .copy_tile
pop bc
dec b
jr nz, .next_tile
ret
; copy bc bytes from hl to de. preserves all registers except af
CopyDataHLtoDE_SaveRegisters:
push hl
push de
push bc
call CopyDataHLtoDE
pop bc
pop de
pop hl
ret
; copy bc bytes from hl to de
CopyDataHLtoDE:
ld a, [hli]
ld [de], a
inc de
dec bc
ld a, c
or b
jr nz, CopyDataHLtoDE
ret
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