STM32f103C8 USB and CAN using together (Unrecognised USB problem)

[UUrcan]

I can not use CANBUS and USB together. I configurated USB and CAN together but PC does not recognise the STM32F103C8 as an USB driver.

When I use only USB without CAN configuration then USB work properly and recognise it as an USB driver.

When I add CAN configuration from different pins (PB8 and PB9) then CANBUS works on these pins but USB not.

How can I recognise the STM32F103C8 as an USB drive to my PC with using CANBUS together? Could you help me about this please?

[Amel NASRI]

Hi @UUrcan​ ,

Unfortunately, you cannot use USB & CAN at the same time for the selected device. To know more about this and the why reason, please refer to this article: https://community.st.com/s/article/FAQ-Concurrent-use-of-USB-and-CAN-with-STM32F103.

Don't forget to answer the question "Was this article helpful?" from article page.

-Amel

[UUrcan]

OK Amel. Thanks for your reply.

But which devices can use both of them (USB and CAN) together at the same time?

[Amel NASRI]

hi @UUrcan​ ,

This is applicable for low, medium-, high- and XL-density STM32F1 devices as precised in the article.

So you can select any other STM32F1 device or a device belonging to other families.

As explained in RM0008:

• Low-density devices are STM32F101xx, STM32F102xx and STM32F103xx microcontrollers where the Flash memory density ranges between 16 and 32 Kbytes.
• Medium-density devices are STM32F101xx, STM32F102xx and STM32F103xx microcontrollers where the Flash memory density ranges between 64 and 128 Kbytes.
• High-density devices are STM32F101xx and STM32F103xx microcontrollers where the Flash memory density ranges between 256 and 512 Kbytes.
• XL-density devices are STM32F101xx and STM32F103xx microcontrollers where the Flash memory density ranges between 768 Kbytes and 1 Mbyte.
• Connectivity line devices are STM32F105xx and STM32F107xx microcontrollers.

-Amel