Hi Chris,
I've no idea if this could cause the problem you describe... but you have the COFIG set to "HS", but seem to be using a 4MHz osc? (which I think would use the "XT" setting).


@ DEVICE PIC16F870, HS_OSC, WDT_On, PWRT_ON, BOD_on, LVP_OFF , DEBUG_OFF, PROTECT_OFF

DEFINE OSC 4
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