STM32F103CBT6: Flash verification fails when writing

[HexF]

• I made serious effort to avoid creating duplicate or nearly similar issue
  This issue extends on issue STM32F103CB: I could not write bin file on my controller.  #1068, which was closed and locked so I can't add to that - hence a new issue.

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• Programmer/board type: STLink v2 Clone and STLink v2
• Operating system an version: Linux (NixOS 20.09)
• Stlink tools version and/or git commit hash: v1.6.0 (nixpkg)
• Stlink commandline tool name: st-flash
• Target chip (and board, if applicable): STM32F103CBT6 (Custom PCB)

nix-shell:~/Projects/brainware]$ sudo st-flash --reset write build/src/brainware.bin 0x08000000
st-flash 1.6.0
2021-03-16T18:47:27 INFO common.c: Loading device parameters....
2021-03-16T18:47:27 INFO common.c: Device connected is: F1 Medium-density device, id 0x20036410
2021-03-16T18:47:27 INFO common.c: SRAM size: 0x5000 bytes (20 KiB), Flash: 0x20000 bytes (128 KiB) in pages of 1024 bytes
2021-03-16T18:47:27 INFO common.c: Attempting to write 15088 (0x3af0) bytes to stm32 address: 134217728 (0x8000000)
Flash page at addr: 0x08003800 erased
2021-03-16T18:47:27 INFO common.c: Finished erasing 15 pages of 1024 (0x400) bytes
2021-03-16T18:47:27 INFO common.c: Starting Flash write for VL/F0/F3/F1_XL core id
2021-03-16T18:47:27 INFO flash_loader.c: Successfully loaded flash loader in sram
 15/15 pages written
2021-03-16T18:47:28 INFO common.c: Starting verification of write complete
2021-03-16T18:47:28 ERROR common.c: Verification of flash failed at offset: 0
stlink_fwrite_flash() == -1

The flashing of the processor seems to fail at this point, as in the aforementioned issue.
One technicality that I have noted is that people are assuming the F103C8 and F103CB chips are the same, and infact they are not.
I have tested the exact same command with a C8 chip, and it worked perfectly fine, but upgrading to a CB chip (which I have had ST confirm are genuine and not counterfeits)

I loaded up a Windows PC with the STLink Utility from ST and it flashed the chip perfectly fine. I was then able to confirm that the flash reads back using st-flash on my Linux machine fine, and it matched byte-for-byte the built firmware.
However, if I ignore the verification failing on Linux, and run the same read command - I get completely random data.

Any pointers on what to do?

[Nightwalker-87]

@HexF: Please use the latest version of the toolset (currently 1.6.1) when reporting bugs. It would also be helpful to know if the error still occurs in the latest develop branch.

[HexF]

Using 9956bde (latest develop commit) I get:

nix-shell:~/Projects.local/brainware]$ sudo st-flash --reset write build/src/brainware.bin 0x08000000
st-flash 1.6.1
2021-03-16T22:34:31 WARN usb.c: NRST is not connected
2021-03-16T22:34:31 INFO common.c: F1xx Medium-density: 20 KiB SRAM, 128 KiB flash in at least 1 KiB pages.
2021-03-16T22:34:31 WARN usb.c: NRST is not connected
file build/src/brainware.bin md5 checksum: 53116e8ca4448facb7c4895364041f7, stlink checksum: 0x00179d53
2021-03-16T22:34:31 INFO common.c: Attempting to write 15088 (0x3af0) bytes to stm32 address: 134217728 (0x8000000)
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08000000 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08000400 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08000800 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08000c00 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08001000 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08001400 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08001800 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08001c00 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08002000 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08002400 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08002800 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08002c00 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08003000 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08003400 erased
2021-03-16T22:34:31 INFO common.c: Flash page at addr: 0x08003800 erased
2021-03-16T22:34:31 INFO common.c: Finished erasing 15 pages of 1024 (0x400) bytes
2021-03-16T22:34:31 INFO common.c: Starting Flash write for VL/F0/F3/F1_XL
2021-03-16T22:34:31 INFO flash_loader.c: Successfully loaded flash loader in sram
 15/ 15 pages written
2021-03-16T22:34:32 INFO common.c: Starting verification of write complete
2021-03-16T22:34:32 ERROR common.c: Verification of flash failed at offset: 0
stlink_fwrite_flash() == -1

Basically the same, just more text

[Ant-ON]

Can you try https://github.com/Ant-ON/stlink/tree/flash_loader_rework? I'm trying to improve a work of bootloaders...

[HexF]

@Ant-ON That seems to have fixed it:

[nix-shell:~/Projects.local/brainware]$ st-flash --reset write build/src/brainware.bin 0x08000000
st-flash 1.6.1
2021-03-22T18:26:14 WARN usb.c: NRST is not connected
2021-03-22T18:26:14 INFO common.c: F1xx Medium-density: 20 KiB SRAM, 128 KiB flash in at least 1 KiB pages.
2021-03-22T18:26:14 WARN usb.c: NRST is not connected
file build/src/brainware.bin md5 checksum: fe4bf5eb73e1a0fc4bfdcf37ff4a651f, stlink checksum: 0x00179d59
2021-03-22T18:26:14 INFO common.c: Attempting to write 15088 (0x3af0) bytes to stm32 address: 134217728 (0x8000000)
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08000000 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08000400 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08000800 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08000c00 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08001000 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08001400 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08001800 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08001c00 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08002000 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08002400 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08002800 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08002c00 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08003000 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08003400 erased
2021-03-22T18:26:14 INFO common.c: Flash page at addr: 0x08003800 erased
2021-03-22T18:26:14 INFO common.c: Finished erasing 15 pages of 1024 (0x400) bytes
2021-03-22T18:26:14 INFO common.c: Starting Flash write for VL/F0/F3/F1_XL
2021-03-22T18:26:14 INFO flash_loader.c: Successfully loaded flash loader in sram
 15/ 15 pages written
2021-03-22T18:26:15 INFO common.c: Starting verification of write complete
2021-03-22T18:26:15 INFO common.c: Flash written and verified! jolly good!
2021-03-22T18:26:15 WARN usb.c: NRST is not connected

[Nightwalker-87]

@HexF Can you test that in a sequence as well to verify this is not a certain coincidence?

[HexF]

Yep, running my ninja -C build flash worked perfectly fine