> > I am currently trying to fix some programming issues with the
Wisp628
> > and a 16F877A.
>
> If you have trouble contact me, the 16F87xA's should program OK (no
> /MCLR that can be used for I/O, no Vpp-before-Vcc mentioned in the
> specs).

Wouter is correct, as usual.  The problems had nothing to do with Vpp
before Vcc, but with a cold solder joint.  I was speculating that it
might be, because of the question raised about the order of Vpp versus
Vcc.

Lesson learned: read the datasheet first!  The programming algorithm
specifically states that Vpp is raised AFTER Vcc (although it MCLR must
rise from 5VDC to 13VDC in less than 72 clocks).

By the way, if anyone new to PIC programming is reading, the Wisp628
programmer is extremely easy and cost effective as a prototype
programmer.  I have yet to see anyone produce a kit with such detailed
instructions and pictures.

Brian Smith

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