>      >  We've run into an interesting problem while trying to optimize an
>      >interface using the 16C63 serial port.
>      >
>      >  The application involves sending just a few bytes to the PIC and
>      then >returning a much larger number from the micro.
>      >
>      >  So, we hit on the (seemingly) clever idea of running the forward
>      >communication at 19K Baud thus avoiding the known BRGH=1 receive
>      >anomalies and the reverse at 115K maximizing our transfer rate.
>      >
>      >  The problem is that it doesn't work!  ...using the suggest coding
>      from >the data book.
>      >  Does anyone have any experience with changing the serial port baud
>      rate >"on the fly"?   Is there some mystic sequence necessary to
>      "reset" or >"re-initialize" the port beyond what is disclosed in the
>      data book?
>      >
>      >Thanks in advance for any suggestions, >   Jen :-)

Try to check for frame errors on both sides first.
After you've changed the baudrate, wait a while so the PC can re-sync on the first startbit. Same
applies to comms in the other direction.
Try sending a zero byte first.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za

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