Olin Lathrop wrote:

> Russell McMahon wrote:
>>> For such a broad question you can only get a likewise broad answer:
>>> "it depends, RTM".
>> 
>> '  I'd interpret the broad question as "having read a cross section
>> of manuals, I find that there are a wide range of situations that
>> apply. It may be that there are best practices, frowned on
>> procedures, most common means of implementation and more which I in
>> my necessarily incomplete knowledge may have failed to pick up on 
>> 
>> So, can anyone skilled in the art and experienced in the ways of the
>> beasts offer some generic advice through what is obviously a bit of
>> a minefield? If you know no more on the subject than I do you may
>> wish to wait with me for pearls of enlightenment from the masters. '
> 
> You may interpret it that way, but that's only one interpretation,
> and good questions don't need interpreting anyway.  He asked what he
> asked, and we should take it at face value.  Wouter's response was
> right on for that.  If the OP want's a better answer, he'll have to
> ask a better question. 

Right. For example, I have one design with a PIC that can run between 3V
and 5V, and often I use ICSP with the PIC's Vdd connected straight to
the 3.3V of the circuit, and it works fine -- except when I need to
reprogram a chip that has previously been protected. In this case, I
need to unpower the circuit and power the chip from the 5V the ICSP
programmer provides, to get the bulk erase working.

So it clearly depends... :)

Gerhard
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