Bitwise IO: Difference between revisions

; are as far left as possible.

inc de ;skip bit 7

ld b,7 ;loop counter

ld a,(de)

or a ;compares accumulator to zero. Assumes a null-terminated string.

; Otherwise compare A to your terminator of choice.

sub &30 ;we're left with 0 if the ascii was "0" and 1 if the ascii was "1"

rl (hl) ;rotate it out of the carry into (HL)

inc de

;a macro that becomes DJNZ <label> on Zilog Z80 and DEC B JR NZ,<label> on Sharp LR35902

inc hl ;next output byte

xor a ;LD A,0

cp b ;compare B to zero

ret z ;if B=0, we're done. No need to adjust the last byte

rlc (hl)

ret</lang>