The timer and port interrupt vector registers seem to be resetting to zero when I run my program. What causes that?
SOLUTION: I don’t have a clue. If you find out, let your instructor know so he can put the answer here. PROBLEM: I am using the H1 bit to generate a port interrupt, but I can’t seem to clear the port interrupt request from the PI/T. SOLUTION: The interrupt may be cleared by clearing the H1S bit in the Port Status Register. You need to write a “1” to this bit to clear it to 0. See Section 2.3 of your PI/T manual. Note that to avoid resetting other bits, you must create a mask where only the H1S bit position is set, and all other bit positions are cleared. PROBLEM: I think I’m clearing the PI/T interrupt, but it seems like the PI/T interrupt pin is still staying low. SOLUTION: Check the PIRQ and TIRQ pins of the PI/T to be sure you have external pull-up resistors attached.
