Ok, I'm stumped. I've been trying to figure this out for the past hour
and a bit, and I've gotten nowhere. I'm working on a project with two
18f252s on a single board. They both run independantly, and have their
own oscilators and ICSP ports. I am using a 2x5 header to isolate the
ICSP signals. I am trying to program using the WARP13a with Redback10a
and a homemade ICSP cable that's about 18 or so inches long. The cable
is 10 conductor ribbon cable. I'm using the WarpCore software, not MPLAB
to run the programmer.

Anyway, ICSP just isn't working. I've verified all the connections, and
they all check out. I've even got to the point of measuring from the ZIF
socket on the programmer to the socket on my board, and everything
matches up. My hex files will program just fine into the chip when it's
in the socket, but not when it's in circuit. It will even program in the
ZIF socket and I happen to have the ICSP cable plugged it still, so I'm
thinking that it's not the cable. I can't even verify in circuit. I've
checked and rechecked my circuit board, and with the ICSP cable plugged
in then I'm only connecting to the chip. I've even puled as much as I
can off the board so there's only a couple of LEDs left, no crystals or
anything else. With the WARP13 diagnostic, I read 4.97V at VDD and
12.86V at VPP on both the ZIF and socket in my circuit.

So, I have no clue what's going on. I can't program in circuit, and if I
program in the ZIF, then toss it into circuit and try to verify, it
fails. I'm getting a bit frustrated, as everything else seems to check
out. Only thing I can think of is the length of the cable and the speeds
used in programming, but would an 18inch length of ribbon cable really
cause so many problems? Anyone have any suggestions?

Help!

Thanks,
Josh
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completely foolproof is to underestimate the ingenuity of complete
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