pic18F6722 issues
Hi all,
I'm trying to bring up a pic design that's using an 18F6722. I've used these parts about 8 times in the past but this one is really stumping me. As far as I can tell, this design is not much different from any of the others. It is an XBEE transceiver for my solar panel system to monitor the current and voltage delivered by my solar panels. This board serially connects to my V-I monitoring board that measures the PV array current and voltage.
When I try to program the PIC, I get "Target Device does not match selected device" error. I see on my scope that the oscillator is not functioning. I'm not sure if that's what is stopping the programming sequence. When I use my MELABS USB programmer to read the device, the Config bytes appear to be set but all code space is "FF" on a part that I just soldered onto the board.
I have all the programmer connections exactly the same as my last functioning design and have the digital PGM pin 43 pulled low on the 64 pin part. I'm using the same 18pf caps on the crystal to ground as I've use MANY time before.
The MCLR pullup is 4.7k Ohms as I've used in the past too.
I'm really stumped on this one...
Has anyone more things check?
Thanks,
Brian
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