I had a problem programming some older 16f877 's today and
thought the solution might be interresting to some (could apply
to other chips as well). The symptom was an abort of the
programming in the first byte or shortly therafter with the
message verify failed at address 0000 , good=xxxx bad =3fff or
something like that.  After trying everything I could think of
like loading old firmware with old software , attempting
different 16f877's etc I finally tried programming it with a
small piece of code as a 16f84 which worked

I examined the CHIPINFO.CID file and discovered the main
difference between the 16f877 and the 16f84 was ProgramDelay=80
instead of  ProgramDelay=40 for the 877 I decided to edit the 40
to 42 and this did the trick.
I am not sure if this was just this batch of chips (all with the
same date code) or that this happens more often.

Peter van Hoof


[PIC] kit 128 programmer and 16f877


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