I know that a flash memory has limited write cycles. Does it also have limited read cycles?
Datasheets of most serial flash memories (like SST25VF series) mention endurance cycles. Does this endurance mean read + write cycles?
Answer
There is no limit to the amount of read cycles you can do, but repetitively reading causes something called read disturb. Essentially, reading lots from the same segment without an erase cycle can cause the data to be read incorrectly, and also corrupt surrounding cells in specialised cases.
More info here http://en.wikipedia.org/wiki/Flash_memory#Read_disturb
Most flash controllers will handle this automatically by shuffling data around, it's usually only a problem with controllerless flash such as on a microcontroller
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