Can we write 1 byte data into flash in stm32wb55

Hi, RBG,

the RM0434 describes the usage of the internal Flash memory. Section 3.3.8 provides useful information on the size of the data that can be written, e.g.:

The Flash memory is programmed 72 bits (a double word, 64 bits plus ECC, 8 bits) at a time.

Programming in a previously programmed double word is only allowed when programming an all 0 value. It is not allowed to program any other value in a previously programmed double word, any attempt sets PROGERR flag in the Flash memory status register (FLASH_SR) or Flash memory CPU2 status register (FLASH_C2SR), except when programming an already programmed double word with an all 0 value.

It is only possible to program a double word (2 x 32-bit data).

• Any attempt to write byte (8 bits) or half-word (16 bits) sets SIZERR flag in the FLASH_xxSR register.
• Any attempt to write a double word that is not aligned with a double word address sets PGAERR flag in the FLASH_xxSR register.

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/Peter

Groups of them anyway...

Perhaps if you're more specific about the end goal, you'll get some better answers / suggestions.