In-Circuit Debugger Mode

[paul borgmeier]

Does this help?
http://ww1.microchip.com/downloads/e...Doc/51242a.pdf
EDIT: Section 2.7.2 looks (possibly) promising

[Darrel Taylor]

Excellent!

Thank you very much Paul. That's exactly what I needed.

I guess my searching skillz need a little work.

Much appreciated!

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[Bruce]

Watcha doin there Mr. wizard?

[Darrel Taylor]

I truely wish I knew.

At this point, it's a Big Idea, searching for a purpose.

Got a lot of little pieces, and like Leggo's, I've got to put them together into something functional.
Just wish I knew what that was going to be.

It started out as a Visual Interface to a Servo driver. But it seems to have taken a left turn somewhere.

[Bruce]

I was just curious.

I tried looking up an appnote on this a while back myself, but it seems to be
some dark secret Microchip doesn't want to divulge.

Strange they would build-in this functionality, and never put anything
together showing how to use it.

[David Barker]

At one time it looked like microchip might be fairly open with ICD and 16 parts. However, for 18 parts they just shut down. I agree with Bruce - it is something they don't want to publish in the public domain...

[Darrel Taylor]

They probably wanted to sell ICD2's without competition. But now that half of Taiwan and Hong Kong, know how to clone it. It's time they Pony'd up. (Not Likely)

And you're right, info on the 18F debugger is hard to come by, but I'm finding little bit's and pieces here and there that are looking promissing.

One interesting point, is that chips like the 18F4550 and 18F4321 etc. in the 44 TQFP package have a dedicated debugger port on the pins that are normally "No Connection". This opens up RB7:6 and MCLR/VPP for normal use, while still having debugger functions. 18F452 doesn't have it.

Probably the best info I've found so far is from http://www.picbook.com

They have a program, QwikBug developed by students at Georgia Tech. That's a debugger for 18F452 and 18F4520 with full source code. They list several Microchip engineers as references, so it looks like they got Microchip to give out a little more info.

Unfortunately, they use the USART for coms to the PC instead of the ICSP port, but it sure is a good start. (well Commented)

Still searching though.

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