Folks,
Before I go off and waste a bunch of time trying to do the impossible (but
hey it may be fun), does anyone have any advice on what is the fastest half
duplex rs323 comms I can expect to get using software only on a 4MHz 16f876
(using a resonator not a crystal)?

I'm currently using the code created by Andy N1YEW and posted on piclist.com
and have this working fine at 19200 baud, but if possible I would like to
run a little faster. I know I should probably be using the built in hardware
but the board layout (not mine) will not allow it. I could also switch to a
higher speed but again I would like to avoid changes to the board. The way
things are I can probably dedicate the entire cpu to the serial code while
transmitting/receiving with the exception of a TMR0 roll over interrupt that
has been coded with minimal register save and just a simple increment of a
counter (approx 5 instructions long), the interrupt occurs every 65535
instructions (TMR0 is using divide by 256 pre-scaler).

Thanks for any help

Andy

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