Cause of STM32 internal flash memory wear

[AOver]

Hello,

I would like some clarification on the internal flash memory wear of a stm32f722ret, which is rated at a minimal 10000 P/E cycles. An example:

Suppose there is a flash block/page/sector with two bytes, A and B. Byte A gets programmed (for example to 0xAB), but not byte B (remains 0xFF).

Is only byte A damaged due to programming, but not byte B? Are only the bits of A that are programmed low damaged?

And does erasing the block afterwards damage only those bits of A? Or are both A and B damaged?

I can't find a definitive answer to these questions.

Kind regards,

Alex

[AvaTar]

And you won't get definitive answers here. ST will not publish such intricate design details on public fora - neither do competitors.

... internal flash memory wear of a stm32f722ret, which is rated at a minimal 10000 P/E cycles.

This is the number guaranteed for the maximum Tj, i.e. highest temperature.

With every drop of (about) 10 deg. C, you can reckon one order of magnitude more cycles.

At room temperature, this will give you several millions of erase/program cycles.