>What I really meant to ask about was
> about anyone's experience with a high volume design which works.

If I had to do it, I would do "autobaud".  That requires the PC to
send at least one known character to the device to measure the bit
time.  An odd-code ASCII char works best, since the start bit is
always zero, you can time the start bit.  Hayes modems, of course,
use 0x41h ("A" of the first "AT command ) to autobaud.

Measure a bit time in cycles and remember it.  Then the
oscillator frequency doesn't matter as long as its stable and
reasonably fast.

If you have to be unidirectional, of course, this won't work.  But if
you can, you get auto baudrate setting in the bargain.

Barry.
------------
Barry King, KA1NLH
Engineering Manager
NRG Systems "Measuring the Wind's Energy"
Hinesburg, Vermont, USA
www.nrgsystems.com