LAUNCHXL-F28379D: C2000 CAN protocol - TMS320F28379D

Hello all,

I want to send adc data over CAN protocol to the local PC. Currently I am using C2000 Launchpad board and can_external_transmit.c example file. I have did the changes in the code for onboard transceiver. I am using PCANVIEW software but I am unable to see the data on the PC. It is showing status as- Error Passive and shows error frames. I have checked CANH and CANL on oscilloscope , they are working fine. Could someone help me to rectify this problem so that I can view the data on local PC (PCANVIEW).

Specs-

board- tms320f28379d launchpad

c200ware - 4 01

ccs - 11.2

//
// FILE:   can_external_transmit.c
//
// TITLE:  Example to demonstrate CAN external transmission
//
//! \addtogroup cpu01_example_list
//! <h1>CAN-A to CAN-B External Transmit (can_external_transmit)</h1>
//!
//! This example initializes CAN module A and CAN module B for external
//! communication. CAN-A module is setup to transmit incrementing data for "n"
//! number of times to the CAN-B module, where "n" is the value of TXCOUNT.
//! CAN-B module is setup to trigger an interrupt service routine (ISR) when
//! data is received. An error flag will be set if the transmitted data doesn't
//! match the received data.
//!
//! \note Both CAN modules on the device need to be
//!       connected to each other via CAN transceivers.
//!
//! \b Hardware \b Required \n
//!  - A C2000 board with two CAN transceivers
//!
//! \b External \b Connections \n
//!  - ControlCARD CANA is on GPIO31 (CANTXA) and GPIO30 (CANRXA)
//!  - ControlCARD CANB is on GPIO8 (CANTXB) and GPIO10 (CANRXB)
//!
//! \b Watch \b Variables \n
//!  - TXCOUNT - Adjust to set the number of messages to be transmitted
//!  - txMsgCount - A counter for the number of messages sent
//!  - rxMsgCount - A counter for the number of messages received
//!  - txMsgData - An array with the data being sent
//!  - rxMsgData - An array with the data that was received
//!  - errorFlag - A flag that indicates an error has occurred
//!
//
//###########################################################################
// $TI Release: F2837xD Support Library v3.05.00.00 $
// $Release Date: Thu Oct 18 15:48:42 CDT 2018 $
// $Copyright:
// Copyright (C) 2013-2018 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions 
// are met:
// 
//   Redistributions of source code must retain the above copyright 
//   notice, this list of conditions and the following disclaimer.
// 
//   Redistributions in binary form must reproduce the above copyright
//   notice, this list of conditions and the following disclaimer in the 
//   documentation and/or other materials provided with the   
//   distribution.
// 
//   Neither the name of Texas Instruments Incorporated nor the names of
//   its contributors may be used to endorse or promote products derived
//   from this software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// $
//###########################################################################

//
// Included Files
//
#include "F28x_Project.h"     // Device Headerfile and Examples Include File
#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_types.h"
#include "inc/hw_memmap.h"
#include "inc/hw_can.h"
#include "driverlib/can.h"

//
// Defines
//
#define TXCOUNT  100
#define MSG_DATA_LENGTH    4
#define TX_MSG_OBJ_ID    1
#define RX_MSG_OBJ_ID    1

//
// Globals
//
volatile unsigned long i;
volatile uint32_t txMsgCount = 0;
volatile uint32_t rxMsgCount = 0;
volatile uint32_t errorFlag = 0;
unsigned char txMsgData[4];
unsigned char rxMsgData[4];
uint32_t canBitRate = 0;
uint32_t status;
tCANMsgObject sTXCANMessage;
tCANMsgObject sRXCANMessage;

//
// Function Prototypes
//
__interrupt void canbISR(void);

//
// Main
//
void main(void)
{
    //
    // Initialize System Control:
    // PLL, WatchDog, enable Peripheral Clocks
    //
    InitSysCtrl();

    //
    // Initialize GPIO and configure GPIO pins for CANTX/CANRX
    // on module A and B
    //
    InitGpio();

    //
    // Setup GPIO pin mux for CAN-A TX/RX and CAN-B TX/RX
    //
    GPIO_SetupPinMux(17, GPIO_MUX_CPU1, 2); //GPIO30 -  CANRXA
    GPIO_SetupPinOptions(17, GPIO_INPUT, GPIO_ASYNC);
    GPIO_SetupPinMux(12, GPIO_MUX_CPU1, 2); //GPIO31 - CANTXA
    GPIO_SetupPinOptions(12, GPIO_OUTPUT, GPIO_PUSHPULL);
    /*
    GPIO_SetupPinMux(10, GPIO_MUX_CPU1, 2); //GPIO10 -  CANRXB
    GPIO_SetupPinOptions(10, GPIO_INPUT, GPIO_ASYNC);
    GPIO_SetupPinMux(8, GPIO_MUX_CPU1, 2);  //GPIO8 - CANTXB
    GPIO_SetupPinOptions(8, GPIO_OUTPUT, GPIO_PUSHPULL);
    */
    //
    // Initialize the CAN controllers
    //
    //CANInit(CANA_BASE);
    CANInit(CANB_BASE);

    //
    // Setup CAN to be clocked off the PLL output clock
    //
    //CANClkSourceSelect(CANA_BASE, 0);   // 500kHz CAN-Clock
    CANClkSourceSelect(CANB_BASE, 0);   // 500kHz CAN-Clock

    //
    // Set up the CAN bus bit rate to 500kHz for each module
    // This function sets up the CAN bus timing for a nominal configuration.
    // You can achieve more control over the CAN bus timing by using the
    // function CANBitTimingSet() instead of this one, if needed.
    // Additionally, consult the device data sheet for more information about
    // the CAN module clocking.
    //
    //CANBitRateSet(CANA_BASE, 200000000, 500000);
    canBitRate = CANBitRateSet(CANB_BASE, 200000000, 500000);

    //
    // Enable interrupts on the CAN B peripheral.
    //
    CANIntEnable(CANB_BASE, CAN_INT_MASTER | CAN_INT_ERROR | CAN_INT_STATUS);

    //
    // Clear all interrupts and initialize PIE vector table:
    // Disable CPU interrupts
    //
    DINT;

    //
    // Initialize the PIE control registers to their default state.
    // The default state is all PIE interrupts disabled and flags
    // are cleared.
    //
    InitPieCtrl();

    //
    // Disable CPU interrupts and clear all CPU interrupt flags
    //
    IER = 0x0000;
    IFR = 0x0000;

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    // This will populate the entire table, even if the interrupt
    // is not used in this example.  This is useful for debug purposes.
    //
    InitPieVectTable();

    //
    // Interrupts that are used in this example are re-mapped to
    // ISR functions found within this file.
    // This registers the interrupt handler in PIE vector table.
    //
    EALLOW;
    PieVectTable.CANB0_INT = canbISR;
    EDIS;

    //
    // Enable the CAN-B interrupt on the processor (PIE).
    //
    PieCtrlRegs.PIEIER9.bit.INTx7 = 1;
    IER |= M_INT9;
    EINT;

    //
    // Enable the CAN-B interrupt signal
    //
    CANGlobalIntEnable(CANB_BASE, CAN_GLB_INT_CANINT0);

    //
    // Initialize the transmit message object used for sending CAN messages.
    // Message Object Parameters:
    //      Message Identifier: 0x5555
    //      Message ID Mask: 0x0
    //      Message Object Flags: None
    //      Message Data Length: 4 Bytes
    //      Message Transmit data: txMsgData
    //
    sTXCANMessage.ui32MsgID = 0x0005;
    sTXCANMessage.ui32MsgIDMask = 0;
    sTXCANMessage.ui32Flags = 0;
    sTXCANMessage.ui32MsgLen = MSG_DATA_LENGTH;
    sTXCANMessage.pucMsgData = txMsgData;

    //
    // Initialize the receive message object used for receiving CAN messages.
    // Message Object Parameters:
    //      Message Identifier: 0x5555
    //      Message ID Mask: 0x0
    //      Message Object Flags: Receive Interrupt
    //      Message Data Length: 4 Bytes
    //      Message Receive data: rxMsgData
    //
    sRXCANMessage.ui32MsgID = 0x0005;
    sRXCANMessage.ui32MsgIDMask = 0;
    sRXCANMessage.ui32Flags = MSG_OBJ_RX_INT_ENABLE;
    sRXCANMessage.ui32MsgLen = MSG_DATA_LENGTH;
    sRXCANMessage.pucMsgData = rxMsgData;
    //CANMessageSet(CANB_BASE, RX_MSG_OBJ_ID, &sRXCANMessage,
      //            MSG_OBJ_TYPE_RX);

    //
    // Initialize the transmit message object data buffer to be sent
    //
    txMsgData[0] = 0x12;
    txMsgData[1] = 0x34;
    txMsgData[2] = 0x56;
    txMsgData[3] = 0x78;

    //
    // Start CAN module A and B operations
    //
    //CANEnable(CANA_BASE);
    CANEnable(CANB_BASE);

    //
    // Transmit messages from CAN-A to CAN-B
    //
    for(;;)
    {
            //
            // Transmit Message
            //
        CANMessageSet(CANB_BASE, TX_MSG_OBJ_ID, &sTXCANMessage,
                          MSG_OBJ_TYPE_TX);
        status = CANStatusGet(CANB_BASE,CAN_STS_TXREQUEST);
        DELAY_US(1000 * 1000);

    }

    //
    // Stop application
    //
    asm("   ESTOP0");
}

//
// CAN B ISR - The interrupt service routine called when a CAN interrupt is
//             triggered on CAN module B.
//
__interrupt void
canbISR(void)
{
    uint32_t status;

    //
    // Read the CAN-B interrupt status to find the cause of the interrupt
    //
    status = CANIntStatus(CANB_BASE, CAN_INT_STS_CAUSE);

    //
    // If the cause is a controller status interrupt, then get the status
    //
    if(status == CAN_INT_INT0ID_STATUS)
    {
        //
        // Read the controller status.  This will return a field of status
        // error bits that can indicate various errors.  Error processing
        // is not done in this example for simplicity.  Refer to the
        // API documentation for details about the error status bits.
        // The act of reading this status will clear the interrupt.
        //
        status = CANStatusGet(CANB_BASE, CAN_STS_CONTROL);

        //
        // Check to see if an error occurred.
        //
        if(((status  & ~(CAN_ES_RXOK)) != 7) &&
           ((status  & ~(CAN_ES_RXOK)) != 0))
        {
            //
            // Set a flag to indicate some errors may have occurred.
            //
            errorFlag = 1;
        }
    }
    //
    // Check if the cause is the CAN-B receive message object 1
    //
    else if(status == RX_MSG_OBJ_ID)
    {
        //
        // Get the received message
        //
        CANMessageGet(CANB_BASE, RX_MSG_OBJ_ID, &sRXCANMessage, true);

        //
        // Getting to this point means that the RX interrupt occurred on
        // message object 1, and the message RX is complete.  Clear the
        // message object interrupt.
        //
        CANIntClear(CANB_BASE, RX_MSG_OBJ_ID);

        //
        // Increment a counter to keep track of how many messages have been
        // received. In a real application this could be used to set flags to
        // indicate when a message is received.
        //
        rxMsgCount++;

        //
        // Since the message was received, clear any error flags.
        //
        errorFlag = 0;
    }
    //
    // If something unexpected caused the interrupt, this would handle it.
    //
    else
    {
        //
        // Spurious interrupt handling can go here.
        //
    }

    //
    // Clear the global interrupt flag for the CAN interrupt line
    //
    CANGlobalIntClear(CANB_BASE, CAN_GLB_INT_CANINT0);

    //
    // Acknowledge this interrupt located in group 9
    //
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP9;
}

//
// End of File