[sdiy] EPROM/flash lifetime

[Barry Klein]

I'd like to expand on the AVR life question:

1) For EPROM's and Flash - is the lifetime a shelf lifetime or data
lifetime? 
 
2)If you take a 10 year old eprom and re-write it is it good for another 10
years or must it be replaced with a NEW part?

3)Has anyone done a study on just what the lifetime is on common ~20 year
eproms has been?  Should we count on our older synths failing for this
problem (or my ham radio, or my scope, or....)

4)Are EPROMs even being made now with ROHS forcing new processes?

Barry