Hi Ken,

The problem as stated by Microchip Tech Support during a phone call:

Any flash processors coming from the Gresham, OR fab MAY have an ICSP
programming problem at 5V VDD.  The processors will program fine with
the low voltage ICSP algorithm.  This programming anomaly does not
effect the normal operation of the processors.

I experienced the problem programming my boards with my ICD2 set to use
its internal 5V VDD.  At 5V, the ICD2 uses algorithm #2.  There were a
predictable number of failures to program this way per lot of boards.
The failed boards were then programmed with  the ICD2 set to use an
external VDD supply of 4.25V.  When the voltage is set this low, the
ICD2 selects algorithm #1 -- which by the way does take a longer time to
program the part.  These boards programmed 100% this way.  Using the
external supply makes programming production quantities more tedious
though.

I don't know if Microchip has published anything about this yet since my
mystery was solved.  The other thing is I didn't feel real warm and
fuzzy about using the ICD2 long term due to the varied environmental
conditions my equipment gets used, so I opted for the PM3 to test the
parts at voltage extremes also.  Still, 100% of the parts are programmed
1st time through 100% of the time.

That's everything I have.

Bill

> -----Original Message-----
> From: piclist-bounces@mit.edu 
> [mailto:piclist-bounces@mit.edu] On Behalf Of Ken Pergola
> Sent: Tuesday, November 09, 2004 10:41 PM
> To: Microcontroller discussion list - Public.
> Subject: RE: [PIC]MPLAB PM3 Universal Device Programmer
> 
> 
> 
> William Bross wrote:
> 
> > And, since we use 877As exclusively
> > right now, the selectable voltage settings keep the flash 
> programming 
> > bug from biting us.
> 
> Hi Bill,
> 
> I'm just curious about this problem you have experienced.
> 
> 1) How does the problem manifest itself?
> 
> 2) Has Microchip confirmed this and published any 
> documentation regarding this?
> 
> 
> Thanks very much for your time.
> 
> Best regards,
> 
> Ken Pergola
> 
> 
> _______________________________________________
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at 
> http://mailman.mit.edu/mailman/listinfo/piclis> t
> 


_______________________________________________
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist