front panels

From: Jack Peacock <peacock_at_simconv.com>
Date: Mon Feb 23 14:53:56 1998

The one thing you could do with a real front panel (not the debugger ROMs
and a keyboard/LED display) is debug new card designs. Remember the Morrow
S-100 extender card with the built-in logic probe? For those of us who
wanted to build our own cards (remember wirewrap too?) but couldn't afford a
home o-scope, much less a logic analyzer, the logic probe and single
stepping front panel were invaluable. You could actually single step
execute an I/O command and see the address and data bus decode on the
peripheral card. And when you finished soldering that new 8KB static RAM
board full of 2102s, you could see the bit change from 1 to 0 right before
your eyes, no better way to find a bad chip or solder joint.

The best thing IMSAI ever did was come out with a good front panel, not that
wiring nightmare that MITS put on the Altair. I still have a running IMSAI
with the front panel (circa 1977), plus an Ithaca Intersystems S-100 with
the front panel, which was only a slight improvement over the IMSAI version.
I also had one homebrew S-100 with the Wameco front panel, which used hex
displays for address and data but otherwise was identical to the IMSAI front
panel. Does anyone remember other front panel S-100 cards besides MITS,
IMSAI, Ithaca, and Wameco? Wasn't there a Byte-8 sold by Olson Electronics
for a while that also had a front panel?
Received on Mon Feb 23 1998 - 14:53:56 GMT