STM32H5-EDataBank_1 - Data not persistent + Read error at 0x09000000

[mani9989]

Hi,

I’m using EDataBank_1 on an STM32 device to store user data after a power cycle. I based my code on the EraseProgram example and made these changes:

What I did:

• Enabled FlashPeripheral and set EDataBank_1 size = 2

• On first boot, I do:
  Init → Erase → Program → Read

• After a reset, I do:
  Init → Read → (optional Program)
  (I skip erase to keep the data)

Problems:

1. After writing, when I read back, I see userConfig is already set, which I didn’t expect.

2. I can’t read memory at 0x09000000 using STM32Programmer. It always gives a read error.

Questions:

• Why does userConfig look configured right after a write?

• How do I check if EDataBank_1 is still uninitialized (virgin) without erasing?

• Is the read error at 0x09000000 due to write failure or ECC error?

• How can I detect write errors or ECC issues?

Goal:

• Save data once

• Read/write it later without erase

• Keep data even after power off

Any help is appreciated. Thanks!

Manikanta

[Sarra.S]

Hello @mani9989, 

You can check this article for ECC errors: Handling ECC errors in STM32H5 series: Reading unwritten OTP and flash data area

Also, check this application note: AN5342, section 3.2: Dealing with ECC errors in flash memory