_lshiftc:
; de = dest
; hl = src
; a = shift count
	push af
		and a, 7
		jr z, .skip_bitshift
		inc a
		ld c, a
.loop_nbits:
		ld b, 30
		push hl,de
			or a
.lshift_bits:
			ld a, (hl)
			rla
			ld (de), a
			inc hl
			inc de
			djnz .lshift_bits
		pop de,hl
		dec c
		jr nz, .loop_nbits
.skip_bitshift:
	pop af
	or a
	rra
	rra
	rra
	or a
	ret z
	ld bc, 0			; make sure bcu is zeroed
	ld c, 30			; c is total length of region to copy bytes to
	ld b, a				; b is number of bytes to set to 0
	xor a				; zero a
.zero_nbytes:
	ld (de), a
	inc de					; increase de
	dec c					; decrease c
	djnz .zero_nbytes		; should stop when b = 0 and c = remaining bytes to copy
	ldir					; hl = LSB of src, de = next byte of dest
	ret