So if I place halt in the middle of my prgm, it would do nothing because the interrupt 1 is running, right? >well: > >nop (00h) does nothing at all, it's a No Operation... wastes 4 cycles >halt (76h) waits until next interrupt... if intrpts are disabled (di) then >CRASH ! _________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com.