and the CONFIG statement Dave provided cannot have the CPD_OFF fuse because it doesn't exist in a 16F628A.INC file. The program won't compile with CPD_OFF in the string.
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I have MCS 5.0.0.3
PBPX 3.0.1.4

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Darrel, I upgraded MPLAB, MCS+ and PBP3.0 as required. No change.
Are you saying that you still can't compile with _CPD_OFF in the config line, even after updating?
If so, you may be compiling for the wrong chip.

My serial input works.
And what about the loopback? Do you have that working.