Option Byte Programming failed upon trying to modify option bytes

[breynard]

Hello! I'm new to STM32 hardware, and I'm having some difficulties getting it running on my Black Pill board with an STM32F411CEU6. It has both Read and Write Protection enabled, and I am trying to disable them using STM32CubeProgrammer through an STLINK V2. However, upon trying change option bytes, it gives me a weird error.

For attempting to change read protection from value 0xFF to 0xAA it gives me this:

16:24:25:038 : Error: Expected value for Option Byte "RDP": 0xAA, found: 0xFF
16:24:25:044 : Error: Option Byte Programming failed Or modified by application after OB_LAUNCH

And similar story for trying to change the write protection values from true to false for all flash sectors:

  16:26:41:386 : Error: Expected value for Option Byte "WRP0": 0x0, found: 0x1
  16:26:41:391 : Error: Expected value for Option Byte "WRP1": 0x0, found: 0x1
  16:26:41:395 : Error: Expected value for Option Byte "WRP2": 0x0, found: 0x1
  16:26:41:399 : Error: Expected value for Option Byte "WRP3": 0x0, found: 0x1
  16:26:41:408 : Error: Expected value for Option Byte "WRP4": 0x0, found: 0x1
  16:26:41:416 : Error: Expected value for Option Byte "WRP5": 0x0, found: 0x1
  16:26:41:428 : Error: Expected value for Option Byte "WRP6": 0x0, found: 0x1
  16:26:41:436 : Error: Expected value for Option Byte "WRP7": 0x0, found: 0x1
  16:26:41:441 : Error: Option Byte Programming failed Or modified by application after OB_LAUNCH

I am on Linux, and the software recognizes the MCU type and ID, so I believe the connection is good. Any help would be appreciated!

[Issamos]

Hello @breynard 

This problem depends on different conditions (level of read protection,Proprietary code readout protection,...) that's why I suggest you to take a look at the parts 3.6.5, 3.6.4 et 3.6.3 of the RM0383. That will give you all details you need to now. I'm suspecting that the read protection is in level 2 and that's going to be impossible to change. 

Best regards.

II

[breynard]

Thank you for the prompt reply. I don't think it's in level 2 read protection, as the value reads 0xFF, not 0xCC. I remember seeing somewhere that anything but 0xAA and 0xCC is level 1 protection. Also, I don't think that will affect the ability to write to option bytes, but I could be mistaken. PCROP is enabled, and upon trying to disable it, I get the same error.

  17:40:06 : Error: Expected value for Option Byte "SPRMOD": 0x0, found: 0x1
  17:40:06 : Error: Option Byte Programming failed Or modified by application after OB_LAUNCH

You know far more than I do though, and if it is truly unrecoverable (either on part of the MCU or the STLINK), I can still return either or both of them.

[Issamos]

Than, this post may be helpful for you.

Best regards.

II

[MikaelM]

hello @breynard ,

as suggested, you could read reference manual RM0383.
You will find page 57/844 :
"The deactivation of the SPRMOD and/or the unprotection of PCROPed user sectors can
only occur when, at the same time, the RDP level changes from 1 to 0. If this condition is not
respected, the user option byte modification is cancelled and the write error WRPERR flag
is set. The modification of the users option bytes (BOR_LEV, RST_STDBY, ..) is allowed
since none of the active nWRPi bits is reset and SPRMOD is kept active."

Best regards

Mikael

[breynard]

Hello @MikaelM 

I interpret that to mean that I can only change protection option bytes at the same time I change RDP from Level 1 (which I think it is at right now with value FF) to Level 0. Upon changing this, the same error as before manifested itself:

  22:47:38 : Error: Expected value for Option Byte "RDP": 0xAA, found: 0xFF
  22:47:38 : Error: Expected value for Option Byte "SPRMOD": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP0": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP1": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP2": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP3": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP4": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP5": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP6": 0x0, found: 0x1
  22:47:38 : Error: Expected value for Option Byte "WRP7": 0x0, found: 0x1
  22:47:38 : Error: Option Byte Programming failed Or modified by application after OB_LAUNCH

Am I misinterpreting, or is my device bricked? Thank you so much for your time, both of you!

[MikaelM]

hello @breynard 

could you just connect, dump option bytes and send me the log file caontaining all option bytes values ?

thanks

Mikael

[breynard]

Hello @MikaelM,

Here is the dump:

      -------------------------------------------------------------------
                        STM32CubeProgrammer v2.14.0                  
      -------------------------------------------------------------------

ST-LINK SN  : B55B5A1A0000000053E8EE01
ST-LINK FW  : V2J39S7
Board       : --
Voltage     : 3.27V
SWD freq    : 4000 KHz
Connect mode: Normal
Reset mode  : Software reset
Device ID   : 0x431
Revision ID : Rev A
Device name : STM32F411xC/E
Flash size  : 512 KBytes (default)
Device type : MCU
Device CPU  : Cortex-M4
BL Version  : 0x0


UPLOADING OPTION BYTES DATA ...

  Bank          : 0x00
  Address       : 0x40023c14
  Size          : 8 Bytes

[==================================================] 100% 



OPTION BYTES BANK: 0

   Read Out Protection:

     RDP          : 0xFF (Level 1, read protection of memories) 

   PCROP Protection:

     SPRMOD       : 0x1 (PCROP enabled. nWPRi bits used for PCROP protection on sector i) 

   BOR Level:

     BOR_LEV      : 0x3 (BOR  OFF    reset threshold level from 1.80 to 2.10 V) 

   User Configuration:

     WDG_SW       : 0x1 (Software watchdog) 
     nRST_STOP    : 0x1 (No reset generated) 
     nRST_STDBY   : 0x1 (No reset generated) 

   Write Protection:

     WRP0         : 0x1 (PCROP protection active on sector i) 
     WRP1         : 0x1 (PCROP protection active on sector i) 
     WRP2         : 0x1 (PCROP protection active on sector i) 
     WRP3         : 0x1 (PCROP protection active on sector i) 
     WRP4         : 0x1 (PCROP protection active on sector i) 
     WRP5         : 0x1 (PCROP protection active on sector i) 
     WRP6         : 0x1 (PCROP protection active on sector i) 
     WRP7         : 0x1 (PCROP protection active on sector i) 

- breynard

[MikaelM]

Hello, @breynard ,

thank you. I will come back to you as soon as possible on this subject.

Best regards

Mikael

[breynard]

Hi @MikaelM,

Thank you for your continued aid in this topic! If there are any issues with the hardware, I can return and buy a new board.

Best regards,

breynard