USB DFU bootloader on STM32F7

[Aymen Jebali]

Posted on February 14, 2018 at 13:35

Hi,

I am currently using the STM32F769I-EVAL MB1219 Rev B board. I wanted to boot the MCU in the DFU bootloader mode, and as the manual suggests I removed the 0 Ohm resistor R124. I also set SW1 to `1`.

This looks like activated the DFU bootloader since it activates some traffic on the USB bus, but the board does not enumerate properly and appears as unknown USB device on my PC.

Reading the options bytes, which should be fine, I got:

 

Could you please suggest a workaround to overcome the USB enumeration problem? probably I am missed something?

Many thanks,

Aymen

[Nesrine M_O]

Posted on February 14, 2018 at 16:30

Hi

aymen.jebali

,

Could you please check your STLINK firmware version?

• If it is an old version (Older than V2J26M15 version) please try to upgrade the ST-link firmware.
• Be sure also that the R124 is correctly removed.

Please refer to this thread

https://community.st.com/0D70X000006SuPJSA0

-Nesrine-

[Aymen Jebali]

Posted on February 14, 2018 at 19:48

Hi Nesrine,

The R124 has been removed.

I don't understand how upgrading the STLink would solve the DFU enumeration problem !

I already read through the thread you suggested but no help.

Thanks,

Aymen

[Aymen Jebali · Accepted solution]

Posted on February 15, 2018 at 12:50

Hello,

Removing the jumper JP14 and solved the issue.

JP14 when connected will make PA11 connected to both CAN1_RX and USB_FS1_DM. Even if CAN bus is not driven this will lead into failure on USB communications.

Regards,

Aymen

[Nesrine M_O]

Posted on February 15, 2018 at 14:39

Hi,

yes in fact  JP14 must be removed when using USB OTG FS.

-Nesrine-

[Aymen Jebali]

Posted on February 15, 2018 at 14:46

Indeed I overlooked that instruction.

I think it's worth it to mention that information or refer to the USB OTG FS chapter in the boot configuration section.

Thanks,

Aymen

[Nesrine M_O]

Posted on February 15, 2018 at 15:00

Hi ,

Please refer to 

http://www.st.com/content/ccc/resource/technical/document/user_manual/group0/8e/5c/0f/b2/85/d5/43/1d/DM00276567/files/DM00276567.pdf/jcr:content/translations/en.DM00276567.pdf

 user manaul

-Nesrine-

[Aymen Jebali]

Posted on February 15, 2018 at 15:04

Thanks Nesrine for your help !

much appreciated