>     It seems that the internal oscillator on the 16F690 is stable and
> precise enough for serial communications as long as the other side  
> has a
> crystal and I maintain VCC at 3.3 volts. Is that assumption  
> correct ? Can I
> really rely on the internal oscillator for USART communications ?  
> Speed will
> be 4800 baud.

I use 9600pbs in a project and it appears to work perfectly. My  
protocol has built in checksumming etc and have rarely seen errors  
despite the fact its in a reasonably harsh environment.
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