Quote Originally Posted by StoneColdFuzzy View Post
PIC16F628A, RB4 does nothing, no matter what. What else could be wrong?
Could be a breadboard problem, could be you have mistaken which pin is RB4 (I have done that), could be an inverted polarity LED you are using or a bad one or open resistor or other wiring error. Without seeing the breadboard and the exact code we are shooting in the dark.