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h p
Associate III
Jun 24, 2025 2:58 PM UTC
Solved

Bootloader and Read-while-write (RWW)

Hello,

we are using a STM32F429.

The bootloader is located in the first 64kB. The firmware in the remaining sectors.

It erases the remaining sectors of the flash and writes the new firmware.

Now, 3.6.5 Read-while-write (RWW) of the reference manual states that "This feature allows to perform a read operation from one bank while an erase or program operation is performed to the other bank."

Does this mean that reads from the same bank as a sector is erased is not allowed?

If so, how should the bootloader update the firmware in Bank 0, where the bootloader sits itself?

Many thanks in advance for your answer!

 

This topic has been closed for replies.
TDK
TDKBest answer
Jun 24, 2025 3:21 PM UTC

If you read and write from within the same bank, the read operation will block until the erase/write operation is complete. There are no issues doing this.

If in separate banks, they can operate in parallel.

"If you feel a post has answered your question, please click ""Accept as Solution""."

2 replies

TDK
TDKBest answer
Jun 24, 2025 3:21 PM UTC

If you read and write from within the same bank, the read operation will block until the erase/write operation is complete. There are no issues doing this.

If in separate banks, they can operate in parallel.

"If you feel a post has answered your question, please click ""Accept as Solution""."
h p
h pAuthor
Associate III
Jun 25, 2025 5:22 AM UTC

I understand. Thank you very much!