PM0073

Reading/programming the STM32Wxxx embedded Flash memory

Doc ID 17766 Rev 5

17/34

Mass Erase

The Mass Erase command can be used to completely erase the user pages of the Flash

memory. The information block is unaffected by this procedure. The following sequence is

recommended:

1.

Enable the FPEC clock.

2.

Check that no Flash memory operation is ongoing by checking the BSY bit in the

FLASH_SR register.

3.

Set the MER bit in the FLASH_CR register.

4.

Set the STRT bit in the FLASH_CR register.

5.

Wait for the BSY bit to be reset.

6.

Read all the pages and verify.

Figure 3.

Flash memory Mass Erase procedure

Read FLASH_CR_LOCK

FLASH_CR_LOCK

= 1

Yes

No

Yes

No

Perform unlock sequency

Write into FLASH_CR_MER

to 1

Write FLASH_CR_STRT to 1

FLASH_SR_BSY

= 1

Check the erase operation by

reading all the addresses in

the user memory

Enable FPEC clock

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