Flash Erase Stall

paulsmitton9 · ‎2008-04-21

Posted on April 21, 2008 at 20:05

Flash Erase Stall

paulsmitton9 · ‎2011-05-17

Posted on May 17, 2011 at 12:31

Page 9 of the STM32 Flash Programming Manual (PM0042) says:

...code or data fetches cannot be made while a write/erase operation is ongoing.

Is there any way to erase a page of flash without stalling all execution for up to 40ms (or write a word to flash without stalling up to 70us)?

All I could think of is perhaps running everything from RAM and avoiding accessing any constant data (not very practical).

Does this also mean that the flash interrput is pretty much useless for anything but WFI?

lanchon · ‎2011-05-17

Posted on May 17, 2011 at 12:31

> All I could think of is perhaps running everything from RAM

that's right.

> and avoiding accessing any constant data (not very practical).

you can place both code and const data on RAM with the proper linker script.

> Does this also mean that the flash interrput is pretty much useless for anything but WFI?

why? the vector table and relevant handlers can be placed in RAM too.