RS-232 Problem (Configuration ?)

Mike Davis wrote: RS-232 is not a problem as long as you have a few tools and some patience. You might change the A3 jumper (temporary) by REMOVING jumpers: TD Pin 1 to Pin 15 RD RD Pin 2 to Pin 16 TD and INSTALLING a jumper: RD Pin 15 to Pin 16 TD This will give you a loopback to your terminal that will test your cabling and the correctness of the handshaking with your terminal. If this does not work, I would look at the handshaking first. If that works, and you have a logic probe, you could change the A3 jumpers back to their original jumpers and using the logic probe, test for the pulses being received at pin 3 on the 8251 at B5. --Doug ========================================= Doug Coward @ home in Poulsbo, WA Analog Computer Online Museum and History Center http://dcoward.best.vwh.net/analog =========================================