STM32 with multiple CAN ports

cpinkstone2 · ‎2012-02-09

Posted on February 09, 2012 at 10:59

Is there any plans to release an STM32F2 or F4 with 3 or 4 CAN ports?

Any ideas on adding external CAN ports if not?

#can-stm32f2-stm32f4

donald2 · ‎2012-02-09

Posted on February 10, 2012 at 04:51

I doubt that there is a big market for that many.

I've used a MCP2515 SPI CAN Controller with the STM32VLDiscovery board. It took me a few days of wasted effort to figure out that PB5 has bugs with SPI1_MOSI, but other than that it worked as expected.

flyer31 · ‎2012-02-11

Posted on February 11, 2012 at 12:40

Just what's really weird: CAN 2 is not accessible in STM32F4, if the Hi Speed USB (ULPI-Interface is used) (Pin clash).

flyer31 · ‎2012-02-13

Posted on February 13, 2012 at 10:44

I hope, that STM considers to allow a further CAN2RX in the pin mapping table (to avoid the pin clash with OTG_HS_ULPI_D7).

May I propose PB7?

As ''replacement'' for CAN2, we now will use a CAN transceiver connected to a USART - we will use USART1_RX/TX on PB6/PB7, and we will drive a LIN protocol on this CAN hardware - which then works also at higher baudrates (at least if all slaves have precise osciallator clocks, which is the case in our application).

As I think, for some applications it might anyway be interesting to be able to switch between CAN protocol and some USART protocol, possibly STM could be convinced to use PB7 in new devices (or best already in new Silicon chip revistions of STM32F4) as additional possibility for CAN2RX?

In our application, we would need USB-Hi-Speed, FSMC (only 16 data lines), CAN1, CAN2.