I know the subject is nothing to do with LF, but I
didn't keep the original thread...
A few months ago someone on one of these two LF reflectors
pointed me at the Enhanced USART in the 16F688 and later PIC
devices, saying how the baud rate could be set as high as Fosc
/ 4. So getting 3M Baud with a 12MHz Xtal for compatibility
with FTDI chip COM ports at thier highest setting.
Who was it and have you managed to do this? I finally got
round to testing a 16F688 at 3Meg and am getting some funny
results that mean sometimes the PIC's EUSART sends the right
data, and sometimes it gets itself tied up in knots, sending
one character several times
It is not a programming error either, as the code works
perfectly at lower baud rates, by just changing the divider.
The nature of the problem looks and feels like something
inherent to the internals of the chip