Problem with internal CAN Bootloader STM32F7

[Pa Ha]

Posted on July 13, 2018 at 08:05

Hello,

i have a problem with the internal bootloader of the STM32F7(67BI).

We have written a tool for communicating with the internal CAN bootloader. The request of the version and the allowed commands, as well as the erasing of the flash are successful.

But when writing it comes to an erroneous behavior. Different waiting times were tried. The same tool programs an STM32F4 successfully.

The problem is as follows:

sometimes during transmission the STM32F7 repeats its ACK message several times without having received data again. The data before the ACK messages are also written to memory just as often.

The following pictures show the transmission and the read-out memory after the transmission:

The first 6 frames (6x8 Byte / 48 Byte @ 0x..00 to 0x..2F) were written correctly. The 6th frame was written twice into the memory (correctly @ 0x..28 and @ 0x..30) and the following frames were shifted by one frame size. This is repeated at irregular intervals and with several bytes of shifting.

Unfortunately I did not find any information or Erata. To what extent are there any undocumented changes between the bootloader on the STM32F4 and the STM32F7?

Thank you in advance for your help.

[Tesla DeLorean]

@ST Community​ Please have an FAE or staff familiar with CAN Bootloader engage

[Pa Ha]

@ST Community​ 

Too bad that after more than one month no help or at least a comment to the problem was created neither here in the forum nor in the OLS Support Portal of ST :(

[sudo112358]

Hi,

I just posted a more or less similar question. We also experienced multiple ACK messages (on a STM32L476 nucleo board). With a more stable power supply of the mcu (larger bypass caps), the multiple ACK error almost disappeared. Perhaps this helps, although I'm not sure this topic is still existent..

Greetings,

Christian

[Tesla DeLorean]

All getting into the weeds here. Discuss with the FAE supporting your account. Staff directly working on these devices don't engage via the forum.