CCS/LAUNCHXL-F280049C: What is the proper setup for external CAN communications?

//#############################################################################
// $TI Release: F28004x Support Library v1.05.00.00 $
// $Release Date: Thu Oct 18 15:43:57 CDT 2018 $
// $Copyright:
// Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
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//#############################################################################

//
// Included Files
//
#include "driverlib.h"
#include "device.h"

//
// Defines
//
#define MSG_DATA_LENGTH    4
#define TX_MSG_OBJ_ID    1

//
// Globals
//
volatile unsigned long i;
volatile uint32_t txMsgCount = 0;
volatile uint32_t errorFlag = 0;
uint16_t txMsgData[4];

//
// Main
//
void main(void)
{
    //
    // Initialize device clock and peripherals
    //
    Device_init();

    //
    // Initialize GPIO and configure GPIO pins for CANTX/CANRX
    // on module A and B
    //
    Device_initGPIO();
    GPIO_setPinConfig(DEVICE_GPIO_CFG_CANRXA);
    GPIO_setPinConfig(DEVICE_GPIO_CFG_CANTXA);

    //
    // Initialize the CAN controllers
    //
    CAN_initModule(CANA_BASE);

    //
    // Set up the CAN bus bit rate to 500kHz for each module
    // Refer to the Driver Library User Guide for information on how to set
    // tighter timing control. Additionally, consult the device data sheet
    // for more information about the CAN module clocking.
    //
    CAN_setBitRate(CANA_BASE, DEVICE_SYSCLK_FREQ, 500000, 16);

    //
    // Initialize the transmit message object used for sending CAN messages.
    // Message Object Parameters:
    //      CAN Module: A
    //      Message Object ID Number: 1
    //      Message Identifier: 0x95555555
    //      Message Frame: Extended
    //      Message Type: Transmit
    //      Message ID Mask: 0x0
    //      Message Object Flags: None
    //      Message Data Length: 4 Bytes
    //
    CAN_setupMessageObject(CANA_BASE, TX_MSG_OBJ_ID, 0x95555555,
                           CAN_MSG_FRAME_EXT, CAN_MSG_OBJ_TYPE_TX, 0,
                           CAN_MSG_OBJ_NO_FLAGS, MSG_DATA_LENGTH);

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

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

    //
    // Transmit messages from CAN-A to CAN-B
    //
    for(;;)
    {
        //
        // Transmit message
        //
        while(1) CAN_sendMessage(CANA_BASE, TX_MSG_OBJ_ID, MSG_DATA_LENGTH, txMsgData);
        txMsgCount++;

        //
        // Increment the value in the transmitted message data.
        //
        txMsgData[0] += 0x01;
        txMsgData[1] += 0x01;
        txMsgData[2] += 0x01;
        txMsgData[3] += 0x01;
        
        //
        // Reset data if exceeds a byte
        //
        if(txMsgData[0] > 0xFF)
        {
            txMsgData[0] = 0;
        }
        if(txMsgData[1] > 0xFF)
        {
            txMsgData[1] = 0;
        }
        if(txMsgData[2] > 0xFF)
        {
            txMsgData[2] = 0;
        }
        if(txMsgData[3] > 0xFF)
        {
            txMsgData[3] = 0;
        }         
    }
}