On 7 Jan 98 at 22:08, XPY-35 wrote: > <snip>...If B is set to 0 right before DJNZ is reached, will it > loop back or quit? And if B is 1, will it loop back? > DJNZ decrements B and then checks for zero. If B was zero prior to executing this instruction, it'll loop 256 times. If B was 1 prior to this instruction, it'll fall through. Steve