> > no, there is only one initial eeprom write during flashing the PIC, the=
n
> > only once again if mode is changed, which usually never happens and if,=
 then
> > months or even years may have gone by. As said, I'm initializing cell #=
0 to
> > $00 for mode 1 and that's it.
> >
> > To answer another question: No, there is only address #0 written and re=
ad,
> > all other cells are unused.
>=20
> OK.
> In that case this is not an issue with "refresh" of the EEPROM.
> More like some random failure.

Umm, yes it is, as Bobs research has showed. My understanding is that on th=
e EEPROMS with the reduced size cells continued reading of the EEPROM will =
eventually create problems as the charge on the cell does leak away due to =
the changes in charge on the other electrodes and tracks around the cell. E=
ventually the stored charge manages to leak away.=20

It was for exactly this reason that Bob came up with his 'majority voting' =
scheme for when the EEPROM started to show signs of problems.

>=20
> One way (as mentioned in another post) is to have multiple
> EEPROM cells that are compared at each read and re-written
> if any cell is different from the others.


--=20
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--=20
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