David VanHorn wrote:
> I've done this in other devices, by specifying several fields for the data,
> and a pointer to which field is in use.  The pointer only gets updated when
> you change fields, so it never wears out in any practical sense.

There is exact number the pointer getting updated for 8-bit devices. It's 256.
256 * 100K =~ 25M, pretty much close to specified value (20M).
Paying attention to numbers makes Engineer according to Olin ;-)


> When writing the data, I do a readback. If the result is different, then
> it's time to change storage locations, and update the pointer. Old data is
> just left to rot.

Wearing out hardware is not a good idea in my opinion.
Change low byte(s) address(es) every 256 counts circularly, don't wait
the result gets different
Who can guarantee that your test reveals worn cell before the cell
reveals you.  Wear out cells equally.

Regards,
Mike.

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist