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; INPUT:
; a = oam block index (each block is 4 oam entries)
; b = Y coordinate of upper left corner of sprite
; c = X coordinate of upper left corner of sprite
; de = base address of 4 tile number and attribute pairs
WriteOAMBlock::
ld h, HIGH(wOAMBuffer)
swap a ; multiply by 16
ld l, a
call .writeOneEntry ; upper left
push bc
ld a, 8
add c
ld c, a
call .writeOneEntry ; upper right
pop bc
ld a, 8
add b
ld b, a
call .writeOneEntry ; lower left
ld a, 8
add c
ld c, a
; lower right
.writeOneEntry
ld [hl], b ; Y coordinate
inc hl
ld [hl], c ; X coordinate
inc hl
ld a, [de] ; tile number
inc de
ld [hli], a
ld a, [de] ; attribute
inc de
ld [hli], a
ret
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