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RM doc request: Please add a note to WWDG + Option byte programming

Question asked by bil.til on Mar 25, 2013
Latest reply on Mar 26, 2013 by bil.til
Hi, after I finally got my option byte programming running nicely (STM32F4).

Just now I recognized that this collides with the WWDG being active (WWDG max time is 69msec, but option byte programming requires a 16kB erase cycle, which needs 300-500msec).

So if I work with WWDG (which for *** sake cannot be stopped by software...), my only possibility is to program the option byte before starting the WWDG.

It is a bit annoying to recognize this only after all programming is completed ... .

Could you please add the following Notes/Warnings in the STM32F4 reference manual:

Note: The maximumg timeout time of WWDG is 69msec. Therefore it is not possible to performe any flash erase / option byte programming, after the WWDG has been activated!

Please perhaps at the following 3 positions:
- In WWDG-Chapter, perhaps 19.2.
- In 3.5, perhaps after "... not guaranteed if a device reset occurs during a Flash memory operation.":
- In 3.6.2