On 20/11/2010 04:36, James Newton wrote:
> Thanks much Dwayne, and everyone else who has replied to this.
>
> I verified the limitations, and found that the MCLR function must be
> disabled from the external pin for the debugger to work at all.
>
> I don't have the ICD2 help file installed (since I don't have an ICD 2) a=
nd
> the PICKit 2 help file doesn't list a Limitations topic group.
>
> I probably wasn't being clear... even with NO external circuitry attached=
,
> just the PICKit2, the RJ11 adapter, and the 12F675 debugging header (all
> stop) I still can't step the chip. I can program it, I can run it (and
> verify that it is running "Hello World" with a meter on GPIO2 pin), and i=
t
> will try to debug, but either run away ignoring the break point, or
> repeatedly step without being commanded to do so (which locks MPLAB up).
>
> I've tried bypass caps on the power pins, pulling MCLR high with a resist=
or,
> and a million other things. I have the later PICKit 2 with the red button=
,
> so it doesn't need the pull ups on the data pins, but I tried that anyway=
,
> etc...
>
> It just doesn't work.
>
> I considered buying a PICKit 3 out of pocket just to see if it would work=
,
> but I think, based on your experience and the comments of others, that I
> will wait and try to save my pennies for an ICD2 or ICD3. Why is the 2 mo=
re
> expensive than the 3?

My advice is to get the ICD3 if you are getting anything - it's far=20
better than the PicKit3(which has had quite a few teething problems),=20
and the ICD2 is now unsupported I believe. The ICD3 is the replacement=20
for the ICD2, and does everything and more for less price. I got one=20
when I needed more than my PicKit2 could handle (debugging PIC32 and so=20
on) and I'm very glad I did, has worked great for me so far over quite a=20
few projects. If the 12F675 is debug friendly with anything (i.e. it's=20
not the chip itself that's got problems), I'd bet on the ICD3 doing okay=20
with it.

Maybe ask Microchip for confirmation about the 12Fs before you go=20
spending, but for PICs in general the ICD3 is a handy thing to have around.
(pity I don't have any 12Fs here, or I would have tried one and reported=20
back..)
By the way, (you probably know this, but just in case) all the help=20
files are available on the Microchip site, and each chip has a page that=20
links to the relevant documents (errata, app notes, etc) so you will=20
probably find info on debugging limitations there.

> Anyway, I was able to get the immediate job done without the debug functi=
on.
> It was fun playing hi-low with a single PIC pin to find the mid point of =
the
> A2D reading on the POT... long story.
>
> Thanks again.
>
> --
> James Newton
> 1-970-462-7764


--=20
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