>
> 5- David contributed another suggestion: write until the read-back is
> wrong. While this probably gets a higher number of writes out of a cell,
> I'm not sure this is safe... couldn't it be that the cell reads back ok
> right after the write, but not, say, after the next power cycle?


I suppose it could.. Depends on the cell structure probably, but I doubt it.

We didn't pick up any problems in accelerated life testing.
None of the systems will likely out-run the counter life in real life.

What David didn't say is how he manages to multiply the count.


I'm not sure what you mean here. My counters were incremented per event.
The idea is that while the guaranteed number of writes is relatively small,
the typical life is significantly larger. So I wanted to get as many counts
into the space as possible.


> The "trick"
> of my suggestion is to use a 3 or 4 byte counter that moves over by one
> byte at every 100k counts. Maybe obvious, maybe not, but it seems to me
> that this is the most efficient way to have a persistent counter for large
> counts in EEPROM -- for whatever reason you might need it.


Works for me. It just dosen't take advantage of the difference between
guaranteed and typical lifetime.
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