On Sun, 14 Apr 1996, John Miskimins wrote:

> Chaipi Wijnbergen wrote:
> >
> > Hello PIC experts,
> >
> > I am developing a small project using the PIC 16C74 and recently needed
> > to change the Crystal from 16MHz to 20MHz. When I did that, a problem
> > started with the asynchronous communication controller, it started to
> > recived wronge characters.
>
>   I have had similar problems.  Two different systems (both based on the '74)
>  with two different
> boards (this does not appear to be a board level problem) both running at
 20MHz.
>   These systems
> were driven by a PC that sent down a sequence of commands and the PIC based
>  boards fed back
> status information so error handling in the PC program handled 'cleaning up'
 the
>  communications
> errors.  Spent quite a bit of time trying to figure out what was wrong and it
>  appeared that the
> PICs were to blame.
>
> - John Miskimins
>
I have the same problem also and still cannot fix it, I think that it is
a bug.

-Newson