Bob Axtell wrote:
> A sleeker approach is to simply write the variable 3 times, rather than 
> just once. When you read it back, read
> all three copies; if one doesn't match, then rewrite all three (using 
> the two that match). In 3 years of use, I've not
> seen another failure. This concept is "best 2 of 3". I used "best 3 of 
> 5" in a military application.

But this doesn't address the same set of issues as the "refresh 
everything" approach, does it?  E.g., if one very rarely-written 
variable has two or more of its duplicates stored next to those of 
frequently-written variables, it could get compromised before you read 
it back again, no?

It seems like your approach is superior specifically when most variables 
are re-written with pretty much the same frequency - or when you can 
segregate them into blocks of quick-changing and slow-changing 
variables, and store them in regions of EEPROM that aren't adjacent 
(however you can determine that).
-- 
Timothy J. Weber
http://timothyweber.org
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