Okay I understand that now. Thanks for the explanation.

Then for ICD2 it is weird. It should be able to program
12F629 with internal MCLR when 12F629 is not self-powered
but it doesn't. This must be a software bug, right? Or is
it a hardware limitation?

Is this a general problem for ICSP programmer if the 
target is self-powered. So even Promate III will not 
work. Am I right? 

It is not a problem for mass production though since most
likely the target power can always be switched off. Anyway
we will not use ICSP any more for mass production.

Regards,
Xiaofan

-----Original Message-----
From: Wouter van Ooijen 
Sent: Tuesday, July 26, 2005 5:00 PM

> Another possibility is to check PICkit 1 source code.
> I have programmed lots of 12F629 with internal MCLR with
> no problems. The firmware and the host software source
> codes are both available from Microchip website.

That is no answer to the problem: the PICkit1 is a programmer-target
combo, so it can switch the target's Vdd at will. The problem is when
the target is self-powered. 

You will run into the same problem when you try to use a PICkit1 to
program a self-powered target.

Wouter van Ooijen
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