Jim,

In answer to your question, Microchip just calls it "In-Circuit
Debug module available from Microchip" in their spec. Roughly 100h
worth of '87x code that loads at the top of code space and is
accessed by the ICD. Details at Microchip.

Re your question to Tony, on other PICs, the stack/TOS is not
available, as far as I know. It may be on the '87x, at least
when the debug bit is set. On the Scenix, shadow regs don't appear
to be available either, but the whole context (W, status, PC) is
stored in shadow automatically.

- Dan Michaels
Oricom Technologies
http://www.sni.net/~oricom
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At 09:50 AM 2/17/00 -0800, you wrote:
>Dan, What's the Microchip supplied module? you mean code? is source
>available? can you decompile it if not?
>
>Debug overhead really doesn't matter as most time is spent waiting for the
>wetware to cycle.
>
>Nice unit (1-chip testbench) you have there! Lots of function for little
>price. Now, if you can just add device programming, bootloader (have to go
>open source for that don't you?), monitor, debug, and improve your user
>interface software.... What do you sell the bare board for?
>
>Tony, That is really interesting code. Correct me if I'm wrong but the ISR
>can't see what the PC was before the interrupt can it? Can you read the
>stack? Scenix has a shadow register that stores the w, PC and something on a
>int IIRC. Reduces interrupt latency? Does the '877 have such a thing?
>Undocumented?
>
>---
>James Newton mailto:jamesnewton@geocities.com 1-619-652-0593
>http://techref.massmind.org NEW! FINALLY A REAL NAME!
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