I'm actually metering directly on the leg straight off the driver IC- it's as if the channel 6 output is not sinking when it should be. I'm out of town till the end of the week so I can't test further. But I know that both chips are inserted properly since I inspected them under bright light and magnification- carefully looking at the gap between the underside of the chip and the dip socket.
I programmed the pic several different times, until I finally think I figured out the proper procedure- the final time I got the correct checksum, so I'm reasonably sure that it is programmed correctly. From memory- I loaded the hex file, setup the pickit3 programmer, voltage is at 5 volts, it read the chip properly, I erased it, then did a blank check, which reported the chip was empty, then I programmed, verified and read it- after each step the checksum reported as 90d4.
Could there be a problem in that I had tried to program it several times (incorrectly) prior to finally figuring out the correct (at least I think correct) steps?
Just saw the post about the stuck FET- I suppose it could be this, but wouldn't I still see the voltage change at the driver ic pin, as the driver sinks 5 volts trying to fire the FET?