I'm using a PIC16F877 USART (rx/tx connected to MAX233) to Transmit data to
a PC.  It's only running at 9600 baud, and it *does* work (kinda!).  Problem
I see is that, I put a "send_byte" call into a tight loop (yes, it tests
TXSTA/TRMT = HIGH before sending), and the output of the '233 turns to s***
after a few seconds!  (the P-P amplitude of the waveform drops to about 6v,
and it looks like it's broken into oscillation).  The input to the '233 is
still rock-solid correct for the character sequence I'm transmitting, but
the evidence (both on the 'scope and on Hyperterm at the receiving end)
shows that things went south.  Has anyone ever seen this symptom?  I've only
ever used MAX232's before, but aside from channel count didn't expect to see
much difference.  Hmm?
Jim

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