IAR-KICKSTART: MSPM0G3507 UART TX + DMA Problem

/*
 * Copyright (c) 2021, Texas Instruments Incorporated
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
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 * *  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;
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 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "ti_msp_dl_config.h"

#define SET     (1)
#define CLEAR   (0)

#define COMM_BUF_SIZE (260U)

#define MS_FACTOR 80000
#define US_FACTOR 80

volatile uint32_t gu32MsFlag;


typedef struct Modbus
{
    uint8_t u08Address;
    uint8_t u08Function;
    uint8_t u08Data[COMM_BUF_SIZE];
}sModbus_t;

sModbus_t sTxMB;

int main(void)
{
    SYSCFG_DL_init();

    __disable_irq();
    __enable_irq();

    NVIC_EnableIRQ(TIMER_MAIN_INST_INT_IRQN);
    NVIC_EnableIRQ(TIMER_MS_INST_INT_IRQN);
    NVIC_EnableIRQ(UART_COMM_INST_INT_IRQN);
    DL_Timer_startCounter(TIMER_MAIN_INST);

    static uint32_t u32Test = 219;

    while (1) {
        do
        {

        }
        while(gu32MsFlag == CLEAR);
        gu32MsFlag = CLEAR;

        sTxMB.u08Address = 1;
        sTxMB.u08Function = 1;
        sTxMB.u08Data[0] = 1;
        sTxMB.u08Data[1] = 1;
        sTxMB.u08Data[2] = 1;
        sTxMB.u08Data[3] = 1;
        sTxMB.u08Data[4] = 1;
        sTxMB.u08Data[5] = 1;
        sTxMB.u08Data[6] = 1;

        DL_GPIO_setPins(GPIO_RS485_SEL_PORT, GPIO_RS485_SEL_PIN);
        DL_DMA_disableChannel(DMA, DMA_COMM_RX_CHAN_ID);

        DL_DMA_setSrcAddr(DMA, DMA_COMM_TX_CHAN_ID, (uint32_t) &sTxMB.u08Address);
        DL_DMA_setDestAddr(DMA, DMA_COMM_TX_CHAN_ID, (uint32_t) (&UART_COMM_INST->TXDATA));
        DL_DMA_setTransferSize(DMA, DMA_COMM_TX_CHAN_ID, 9);
        DL_UART_clearInterruptStatus(UART_COMM_INST, DL_UART_IIDX_DMA_DONE_TX);
        DL_DMA_enableChannel(DMA, DMA_COMM_TX_CHAN_ID);


        DL_Timer_setLoadValue(TIMER_MAIN_INST, u32Test);
        u32Test++;

        if(u32Test >= 500)
        {
            u32Test = 159;
        }

    }
}

void TIMER_MS_INST_IRQHandler(void)
{
    switch(DL_Timer_getPendingInterrupt(TIMER_MS_INST))
    {
        case DL_TIMER_IIDX_ZERO:
            gu32MsFlag = SET;
            break;

        default:
            break;
    }
}

void TIMER_MAIN_INST_IRQHandler(void)
{
    switch(DL_Timer_getPendingInterrupt(TIMER_MAIN_INST))
    {
        case DL_TIMER_IIDX_LOAD:
            DL_GPIO_setPins(GPIO_EMIT_PORT, GPIO_EMIT_PULSE_PIN);
            DL_Common_delayCycles(6*US_FACTOR);
            DL_GPIO_clearPins(GPIO_EMIT_PORT, GPIO_EMIT_PULSE_PIN);
            break;

        default:
            break;
    }
}

void UART_COMM_INST_IRQHandler(void)
{
    switch (DL_UART_Main_getPendingInterrupt(UART_COMM_INST))
    {
    case DL_UART_MAIN_IIDX_BREAK_ERROR:
    case DL_UART_MAIN_IIDX_OVERRUN_ERROR:
    case DL_UART_MAIN_IIDX_FRAMING_ERROR:
    case DL_UART_MAIN_IIDX_NOISE_ERROR:
        break;

    case DL_UART_MAIN_IIDX_EOT_DONE:
        DL_GPIO_clearPins(GPIO_RS485_SEL_PORT, GPIO_RS485_SEL_PIN);
        break;

    }
}