On Mon, 07 Apr 2003 12:42:27 -0500, you wrote: Crap. Oh well, I was planning a Revision B anyway, to take care of the bugs I already discovered (such as DFSE skipping on error like an RF08 instead of skip-on-no-error). I guess I'll have to figure out how to clear the LS191 counters I used for registers. Maybe there's a 4 bit counter with a clear input I can use. The simplest way would be to force 0's into the load inputs to the counters for EMA and EA and strobe the clock line with that IOT, but that would require a couple of chips and there is just no more room (and keep the board "cheap", standard 160x100mm Eurocard size and two-layer). I could put a lot more logic on a 4-layer board but they cost a LOT more. All those 12-bit busses take up a lot of PCB real estate! Meanwhile I think it'll work with a non-expanded (4K) machine like my 8/L ;) Back to the drawing board! -Charles