> I used to use a EPROM for storing code, but I found that some
> circuits use flash for storing code instead. What is the difference
> between these two ways of code storage? Which is better?

Hi John, AIUI, the retention times for both are 40+ years. EEPROM
can be written to 10x more than Flash, typically 100k min vs 10k min,
and on a single byte basis, rather than blocks. If this is seldomly-changing
data (eg parameter modification or "learning") then either EEPROM or
Flash will do

Microchip have a number of ANs for EEPROM that are worth
reading. They cover the write mechanism (eg using lower Vcc to
maximise write endurance) to maximising writes in an array

Dig up ANs 536, 537, 562, 601, 602, 1019

TB072, "Flash memory technology : Considerations for design"

http://ww1.microchip.com/downloads/en/AppNotes/91072a.pdf

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