Bob,

Can you elaborate on your method of refreshing?  Or a link to what Microchi=
p recommends?  This may be one of my problems I have been fighting with a c=
lient.

--- On Mon, 10/5/09, Bob Axtell <engineer@cotse.net> wrote:

> From: Bob Axtell <engineer@cotse.net>
> Subject: Re: [PIC] 16F88 EE Corruption?
> To: "Microcontroller discussion list - Public." <piclist@mit.edu>
> Date: Monday, October 5, 2009, 7:57 AM
> Sean Breheny wrote:
> > Bob,
> >
> > Do you have more information about this? My reading of
> the Mchip docs
> > suggests that the problem is not reads but writes to
> one cell
> > affecting other cells in the array, so that writing
> address 0 and then
> > writing address 1 10,000 times, if I try to then read
> address 0, I may
> > get garbled data - so I need to make sure the refresh
> address 0 after
> > every N writes to any cell in the array. In other
> words, if I simply
> > write data once, I should then be able to read it
> indefinitely with no
> > further refreshes.
> >
> > Sean
> >
> >=A0=A0=A0
> I thought this was settled years ago; the PICforum and the
> PIClist =

> should all have archives on it.
> Trust me, if you did nothing but read EEPROM data
> repeatedly, in a few =

> days, the data will be
> corrupted, regardless of where it is in the array. And yes,
> there=A0 is =

> interaction with other data
> in close proximity.=A0 The read process, like the write
> process, slowly =

> erodes the data, as does
> other lesser-occurring effects, such as radiation, cosmic
> rays, heat, etc.
> =

> In years past, PICs were made with thicker interconnections
> and better =

> isolation for the EEPROM
> arrays, and errors in EEPROM data was almost unheard of.
> But as the =

> devices have become smaller
> and the protection less, the "dark side" of smaller die
> sizes begins to =

> show up.
> =

> Refresh it en masse as Microchip recommends, or use my
> "best of" =

> algorithm and refresh it as needed.
> My algorithm just increases cell life.
> =

> --Bob
> -- =

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