PCROP Not disabled after RDP Regression, Option change not possible in RDP0

[aco990]

Hello everyone,

I'm experimenting PCROP activation on stm32h743 following this ST-tutorial: https://youtu.be/7Wr90XFA8_Q?si=tDpqUtMdin9Oyn-P

The activation works fine but i cannot disable PCROP using CubeProgrammer.
I did a RDP1 to RDP0 regression with DMWP1 checked but the PCROP is still active

After RDP regression i can se that the unprotected flash are is erase:

But not the protected one:

I can also not change the option bytes anymore, even RDP0 to RDP1 does not work

How can i recover from this situation ?

@Jocelyn RICARD, @Fred 

[aco990 · Accepted solution]

Hi @Jocelyn RICARD ,

now PCROP is removed and the device is working fine! :)
If you encounter the same problem a "bank mass erase with automatic protection-removal" as described in the reference manual could help you:

__HAL_FLASH_CLEAR_FLAG_BANK1(FLASH_FLAG_ALL_ERRORS_BANK1);
HAL_FLASH_OB_Unlock();

SET_BIT(FLASH->PRAR_PRG1, FLASH_PRAR_DMEP);
uint32_t temp = ~((0xFFF << 0) | (0xFFF << 16));
FLASH->PRAR_PRG1 &= temp;  // Clear bits 11:0 and 27:16
FLASH->PRAR_PRG1 |=  (2 << 0);
FLASH->WPSN_PRG1 = 0xFF;

HAL_FLASH_Unlock();
SET_BIT(FLASH->CR1, FLASH_CR_BER);
SET_BIT(FLASH->CR1, FLASH_CR_START);
while (READ_BIT(FLASH->SR1, FLASH_SR_QW) > 0) {} // Wait for erase completion

[Meenakshi]

Enable and Disable the SPRMOD check box 

ENABLE the SPRMOD: 

Step1: Connect the MCU via JTAG/SWD 

Step 2: Open the STM32CubeProgrammer or Download the STM32CubeProgram- Link: https://www.st.com/en/development-tools/stm32cubeprog.html 

Step 3: Open STM32CubeProgrammer and press the Connect button. 

Step 4: Go to Option bytes 

Step 5: Check the SPRMOD 

Step 6: Successfully Enable the flash protection 

Disable the SPRMOD: 

Step 1: MCU has RESET switch (SW 1). Press the Switch (Hardware Reset Switch) 

Step 2: Disconnect the ST_Link 

Step 3: Change the Mode to Under reset and Change the Reset mode to Hardware reset. 

Step 4: After Connect the MCU via ST_Link 

Step 5: Change the RDP from AA to BB 

Step 6: Click Apply 

Step 6: Change RDP to AA and Uncheck the SPRMOD 

Step 7: Click Apply 

Step 8: Finally Disconnect and Connect the MCU for checking process.