CAN.getCanId() gets the ID of the TX MSG insted of the RX MSG

[Damians99]

I send a message periodically (100 Hz) with the CAN-SHIELD (MPC2515). In parallel, I execute the following function:

while (CAN_MSGAVAIL == CAN.checkReceive())
    {
        CanRxInterrupt();
        //Serial.println("MSG detects on RX");
    }


void CanRxInterrupt() {

    unsigned int canId = CAN.getCanId();
    unsigned char len;
    unsigned char buf[8];
    CAN.readMsgBuf(&len, buf);

    Serial.println(canId, HEX);

CAN_MSGAVAIL == CAN.checkReceive()

works perfectly with an incoming message and CanRxInterrupt() is called when a MSG is incomming. However, the following line:

unsigned int canId = CAN.getCanId()

always returns the ID of the just periodically sent message and not that of the incoming message. Sommetimes when the incomming MSG ist sent with a verry high frequence i got the correct ID, but nearly never.

• OS: Windows 11, Arduino, VS Code