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MCU-PLUS-SDK-AM263X: Sending Can Messages at a higher frequency

Part Number: MCU-PLUS-SDK-AM263X

Trying to send multiple CAN messages right after each other. But the code only sends the first message if there is no delay between sending messages.

void TorqueCalculationTask(void *pvParameters) {
    uint64_t throttlePosition = 10;
    uint64_t steeringPosition = 0;
    CANMessage rrMessage;
    CANMessage rlMessage;
    CANMessage frMessage;
    CANMessage flMessage;


    while (1) {
//        if (xSemaphoreTake(torqueValuesMutex, portMAX_DELAY)) {
//            readThrottle(); // Read the throttle value at each cycle
            throttlePosition = throttle_post_transfer;
            steeringPosition = steering_post_transfer;

            if (currentState == STATE_READY_TO_DRIVE && !brakePressed) {
                calculateTorque(throttlePosition, torqueValues, steeringPosition);
                createAMKCanMessage(0x1234, 1500, torqueValues[frontLeftInv], torqueValues[frontLeftInv+1], flMessage.message);
                flMessage.id = 0x105; // Set the appropriate CAN ID
                flMessage.message_length = 8;


                createAMKCanMessage(0x1234, 1500, torqueValues[frontRightInv], torqueValues[frontRightInv+1], frMessage.message);
                frMessage.id = 0x106; // Set the appropriate CAN ID
                frMessage.message_length = 8;

                createAMKCanMessage(0x1234, 1500, torqueValues[rearRightInv], torqueValues[rearRightInv+1], rrMessage.message);
                rrMessage.id = 0x107; // Set the appropriate CAN ID
                rrMessage.message_length = 8;

                createAMKCanMessage(0x1234, 1500, torqueValues[rearLeftInv], torqueValues[rearLeftInv+1], rlMessage.message);
                rlMessage.id = 0x108; // Set the appropriate CAN ID
                rlMessage.message_length = 8;


//                App_mcanSendCustomMsg(newMsg.id, MESSAGE_TYPE_STANDARD, MCAN_DATA_SIZE_8BYTES, newMsg.message);
//                if (xSemaphoreTake(canQueueMutex, portMAX_DELAY) == pdTRUE) {
                    xQueueSendToBack(canQueue, &rrMessage, portMAX_DELAY);
                    xQueueSendToBack(canQueue, &frMessage, portMAX_DELAY);
                    xQueueSendToBack(canQueue, &rlMessage, portMAX_DELAY);
                    xQueueSendToBack(canQueue, &flMessage, portMAX_DELAY);
                    xSemaphoreGive(canQueueMutex);

//                }

//            }
//            xSemaphoreGive(torqueValuesMutex);
        }
        vTaskDelay(pdMS_TO_TICKS(5)); // Adjust task delay as needed
    }
}

void CanMessageSendTask(void *pvParameters) {
    CANMessage msg;
    TickType_t lastWakeTime;
    const TickType_t frequency = pdMS_TO_TICKS(1);

    while(1){
        while (xQueueReceive(canQueue, &msg, portMAX_DELAY)) {
           vTaskSuspendAll();
           App_mcanSendCustomMsg(msg.id, MESSAGE_TYPE_STANDARD, MCAN_DATA_SIZE_8BYTES, msg.message);
           xTaskResumeAll();
        }



    }
}

int32_t App_mcanSendCustomMsg(uint32_t msgId, uint8_t msgType, uint8_t dlc,
                           const uint8_t *data) {
    MCAN_TxBufElement txMsg;
    uint32_t bufNum = 0U;  // Using first buffer for simplicity
    int32_t status;

    /* Initialize message to transmit */
    MCAN_initTxBufElement(&txMsg);

    /* Configure message ID based on type */
    if (msgType == MESSAGE_TYPE_STANDARD) {
        txMsg.id = (msgId & MCAN_STD_ID_MASK)
                   << MCAN_STD_ID_SHIFT;  // Standard ID
        txMsg.xtd = FALSE;                // Indicating standard identifier
    } else {
        txMsg.id = msgId & MCAN_EXT_ID_MASK;  // Extended ID
        txMsg.xtd = TRUE;                     // Indicating extended identifier
    }

    /* Configure DLC */
    txMsg.dlc = dlc;

    /* CAN FD frame format and BRS can be configured based on application needs */
    txMsg.fdf = FALSE;  // Not a CAN FD frame
    txMsg.brs = FALSE;  // Baud rate switching not used

    /* Copy data to the message buffer */
    for (uint32_t i = 0U; i < gMcanDataSize[dlc] && i < sizeof(txMsg.data); i++) {
        txMsg.data[i] = data[i];
    }

    /* Write message to Message RAM */
//    MCAN_writeMsgRam(gMcanBaseAddr, MCAN_MEM_TYPE_BUF, bufNum, &txMsg);
    MCAN_writeMsgRam(gMcanBaseAddr, MCAN_MEM_TYPE_FIFO, bufNum, &txMsg);


    /* Add request for transmission */
    status = MCAN_txBufAddReq(gMcanBaseAddr, bufNum);
    return status;
}

Unless I add "vTaskDelay(pdMS_TO_TICKS(1));" after each transmission only the message with id 0x107 (the first one added to the queue) gets sent. Is there a way of sending message after one Tx is complete rather than having to add a manual time delay?

Expected frequency of messages is about 1500Hz so a 1 millisecond delay is not a viable option for me

  • Hello,

    Yes, you should check for transmission completion instead of adding delay.  Please explore MCAN_INTR_SRC_TX_FIFO_EMPTY before new transmission.

     

    #define MCAN_INTR_SRC_TX_FIFO_EMPTY             (MCAN_IR_TFE_MASK)
    /**< Tx FIFO Empty interrupt */

    Best Regards,
    Gunjan