Well, folks.  I wimped out and bought a BlackBox DB25/RS-232
converter.  It should be at our front door, porch pirates not
withstanding, in a couple of weeks.  Fourty years ago, I
interfaced a speech synthesizer board with the Syntronix
interface for an Apple II computer.  It took me several weeks to
get it working correctly.  The speech board had a Busy line data
flow stopper and the Apple II printer card needed the ACK signal
which is a pulse of about 500 nanoseconds.  I ended up taking the
Busy line from the speech board and it's trailing edge fired a
74-121 pulse generator chip.  I seem to recall that you can make
it fire on either the leading edge or trailing edge by wiring a
couple of pins differently.

	I learned a bunch of things in that project back in 1979,
one of them is to be paranoid about good grounding.  Some of the
noise on the ground wire from the data lines going up and down
looked a lot like ACK pulses so the speech was a bit skippy and
cleaned up a lot when there were no extra pulses that looked like
ACK's.

	Hopefully, this converter will let me sample the output
of the parallel port well enough to do the BIOS setups when
needed.

	I figure the extra dough which was not a terrible outlay
buys time that would just get otherwise wasted and I can get on
with other things.

Martin
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