In message  <33D7FF5F.A3D1DBA8@flash.net> PICLIST@MITVMA.MIT.EDU writes:

> I just assumed that the F84 would program fine, and the first
> couple of times it did. Using the Nigel software, I was able to
> burn a few versions of a small LED flasher program I wrote.
> But now the F84 is dead, and I can't seem to find any PC
> software to fix it.

I don't have an F84 to try, but as soon as I get hold of one I'll update the
DOS software to program either the 'C' or 'F' versions.

> I have a very strong feeling that code protection was turned on
> incorrectly by the Nigel software, which of course thought it was
> programming a C84 and not an F84. So what I need now is a program
> that can fix the code protection settings on my poor dead F84. These
> things are not cheap, and right now I have about $70 of worthless
> PIC junk sitting next to me, with more on the way. Does anyone have
> or is in the process of writing software to program the F84? Ben
> Wirz tells me that the C84 is dead, and thus, I don't want to end
> up working with a discontined chip. Pretty soon most PIC users will
> have to switch to the F84, so can some nice person please write
> software to program the F84 now, before I end up burning all this
> stuff <no pun intended>??

The main difference with the F84 is that the WDT bit is inverted, if you
set it to the opposite of what you require, it should work OK.

> I have talked to Don and Ben privately via E-Mail about this, but
> I thought I'd throw the question out to the group.
>
> Again, the F84 refuses to program, however, it has been erased by the
> Nigel software, so I am assuming it is effectively "blank." The Nigel
> software reports a configuration setting of 1F, but I thought the
> configuration word was 14 bits, not 8?

The C84 only uses one bit for code protection, so my software strips off
all the other unused bits. The F84 uses more than one code protection bit,
and my Windows software now addresses all the bits as required for the F84.

However, I haven't been able to test it yet, due to lack of an F84.

> Does anyone have any ideas on what else the problem could be with
> my F84? I'm hoping somebody will just tell me I'm an idiot and
> show me how to fix it in ten minutes. :-)

My only suggestion is to try your F84 in someone elses programmer, to prove
wether your chip or programmer is at fault.

> BTW, I have had the same problem with the Windows version of Nigel's
> programming software. It refuses to program, and is unable to set the
> fuse settings.

The latest Windows beta version now has an erase button included, I've not
released it yet, but it should be in the next week or so - perhaps that
might help?.

Nigel.

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        | Nigel Goodwin   | Internet : nigelg@lpilsley.demon.co.uk     |
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