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; copy b bytes of data from hl to de, but only during hblank
HblankCopyDataHLtoDE:
push bc
.loop
ei
di
ldh a, [rSTAT] ;
and STAT_LCDC_STATUS ;
jr nz, .loop ; assert hblank
ld a, [hl]
ld [de], a
ldh a, [rSTAT] ;
and STAT_LCDC_STATUS ;
jr nz, .loop ; assert still in hblank
ei
inc hl
inc de
dec b
jr nz, .loop
pop bc
ret
; copy c bytes of data from de to hl, but only during hblank
HblankCopyDataDEtoHL:
push bc
.loop
ei
di
ldh a, [rSTAT] ;
and STAT_LCDC_STATUS ;
jr nz, .loop ; assert hblank
ld a, [de]
ld [hl], a
ldh a, [rSTAT] ;
and STAT_LCDC_STATUS ;
jr nz, .loop ; assert still in hblank
ei
inc hl
inc de
dec c
jr nz, .loop
pop bc
ret
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