Rémi LAUNAY

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6 years, 1 month ago.

Using CAN on a nucleo f303k8

Hello,

Does anyone know how to use CAN communication on NUCLEO-F303K8 with a MCP2551? With this example : https://developer.mbed.org/users/hudakz/code/CAN_Hello/ only the initialization works with pins PA_11 and PA_12, for the other pins it crashes at the initialization of the CAN class, I do not detect any signal to a oscilloscope.

Rémi

1 Answer

Zoltan Hudak
6 years, 1 month ago.

Hello Rémi,

  • According to the board pinout as well as peripheral pin definitions only one CAN channel is available on a NUCLEO-F303K8 board. So it's OK that other pins do not work as CAN interface.
  • Could you please explain in more details your configuration:
    • Do you connect at least two nodes to the CAN bus?
    • What messages are printed to the serial terminals running on the PCs connected over serial line to the mbed boards?
    • What do you mean that only initialization works?

Hello Zoltan,

Thanks for your answer. Finally I got it working by changing the wiring and using this code.

CAN on F303K8

#include "mbed.h"
#include "CAN.h"

Ticker ticker;
DigitalOut led(LED1);
char counter = 0;
Serial pc(USBTX, USBRX);
class Sender{
  private:
    CAN  & can;
  public:
    Sender(CAN & c) : can(c) {
    }
    void send() {
        pc.printf("send()\n");
        if(can.write(CANMessage(1337, &counter, 1))) {
            counter++;
            pc.printf("Message sent: %d\n", counter);
            led=!led;
        }
  }

};


int main() {
  pc.baud(9600);          // set Serial speed


    pc.printf("Hello World!\n");
    CAN can(PA_11, PA_12);
    can.frequency(500000);
    Sender sender(can);
    pc.printf("main()\n");
    ticker.attach(callback(&sender,&Sender::send), 1);
    CANMessage msg;
    while(1) {

        if(can.read(msg)) {
            pc.printf("Message received: %d\n", msg.data[0]);
        }
        if(can.rderror() || can.tderror()){
          pc.printf("rderror:%d\n",can.rderror());
          pc.printf("tderror:%d\n",can.tderror());
          can.reset();
        }
        wait(0.2);
    }
}

I had a problem with the CAN constructor when it was outside the main function.

posted by Rémi LAUNAY 09 Apr 2018