AM2634: I want to use UART in DMA mode using Interrupt.

Tool/software:

Hello,

I am trying to use UART in DMA mode with interrupts, and I am referring to the following resources: (1. UART Echo DMA, 2. UART Echo Callback). However, I am encountering a problem where the main function gets stuck in the uart_echo_dma function, waiting for the read and write operations to complete.

Here is a snippet of my code:

int main(void)
{
System_init();
Board_init();

uart_echo_dma(NULL);  // stuck here.

GPIO_setDirMode(LED_BASE_ADDR, LED_PIN, LED_DIR);
while(1)
{
GPIO_pinWriteHigh(LED_BASE_ADDR, LED_PIN);
ClockP_sleep(1);
GPIO_pinWriteLow(LED_BASE_ADDR, LED_PIN);
ClockP_sleep(1);
}

Board_deinit();
System_deinit();

return 0;
}

I am sharing my system configuration snapshot for reference.

i am sharing my uart_echo_dma file code, check i am doing right or wrong:

/*
 * uart0_echo_dma.c
 *
 *  Created on: 04-Nov-2024
 *      Author: SahilShakilMalpekar
 */



#include <string.h>
#include <kernel/dpl/DebugP.h>
#include "ti_drivers_config.h"
#include "ti_drivers_open_close.h"
#include "ti_board_open_close.h"

#define APP_UART_BUFSIZE              (200U)
#define APP_UART_RECEIVE_BUFSIZE      (8U)

uint8_t gUartBuffer[APP_UART_BUFSIZE];
uint8_t gUartReceiveBuffer[APP_UART_RECEIVE_BUFSIZE];
volatile uint32_t gNumBytesRead = 0U, gNumBytesWritten = 0U;

/* Semaphore to indicate Write/Read completion used in callback api's */
static SemaphoreP_Object gUartWriteDoneSem;
static SemaphoreP_Object gUartReadDoneSem;

#define APP_UART_ASSERT_ON_FAILURE(transferOK, transaction) \
    do { \
        if((SystemP_SUCCESS != (transferOK)) || (UART_TRANSFER_STATUS_SUCCESS != transaction.status)) \
        { \
            DebugP_assert(FALSE); /* UART TX/RX failed!! */ \
        } \
    } while(0) \

void uart_echo_dma(void *args) {
  int32_t transferOK, status;
  UART_Transaction trans;

  Drivers_open();
  Board_driversOpen();

 // DebugP_log("[UART] Echo example DMA mode started ...\r\n");
  status = SemaphoreP_constructBinary(&gUartWriteDoneSem, 0);
  DebugP_assert(SystemP_SUCCESS == status);

  status = SemaphoreP_constructBinary(&gUartReadDoneSem, 0);
  DebugP_assert(SystemP_SUCCESS == status);

  UART_Transaction_init(&trans);

  /* Send entry string */
  gNumBytesWritten = 0U;
  trans.buf = &gUartBuffer[0U];
  strncpy(trans.buf,
          "This is uart echo test DMA callback mode\r\nReceives 8 characters "
          "then echoes back. Please input..\r\n",
          APP_UART_BUFSIZE);
  trans.count = strlen(trans.buf);
  CacheP_wb((void *)trans.buf, trans.count, CacheP_TYPE_ALL);
  transferOK = UART_write(gUartHandle[CONFIG_UART_CONSOLE], &trans);
  APP_UART_ASSERT_ON_FAILURE(transferOK, trans);

  /* Wait for write completion */
  SemaphoreP_pend(&gUartWriteDoneSem, SystemP_WAIT_FOREVER);
  DebugP_assert(gNumBytesWritten == strlen(trans.buf));

  /* Read 8 chars */
  CacheP_wbInv((void *)&gUartReceiveBuffer[0U], APP_UART_RECEIVE_BUFSIZE,
               CacheP_TYPE_ALL);
  gNumBytesRead = 0U;
  trans.buf = &gUartReceiveBuffer[0U];
  trans.count = APP_UART_RECEIVE_BUFSIZE;
  transferOK = UART_read(gUartHandle[CONFIG_UART_CONSOLE], &trans);
  APP_UART_ASSERT_ON_FAILURE(transferOK, trans);

  /* Wait for read completion */
  SemaphoreP_pend(&gUartReadDoneSem, SystemP_WAIT_FOREVER);
  DebugP_assert(gNumBytesRead == APP_UART_RECEIVE_BUFSIZE);

  /* Transmit received data on RFID_READER2 UART */
  gNumBytesWritten = 0U;
  trans.buf = &gUartReceiveBuffer[0U];
  trans.count = APP_UART_RECEIVE_BUFSIZE;
  CacheP_wb((void *)trans.buf, trans.count, CacheP_TYPE_ALL);
  transferOK = UART_write(gUartHandle[CONFIG_UART_CONSOLE], &trans);
  APP_UART_ASSERT_ON_FAILURE(transferOK, trans);

  DebugP_log("[UART] Transmitting to RFID_READER2 ...\r\n");
  /* Wait for write completion */
  SemaphoreP_pend(&gUartWriteDoneSem, SystemP_WAIT_FOREVER);
  DebugP_assert(gNumBytesWritten == APP_UART_RECEIVE_BUFSIZE);

  /* Echo chars entered back to the SERVICE_PORT */
  gNumBytesWritten = 0U;
  trans.buf = &gUartReceiveBuffer[0U];
  trans.count = APP_UART_RECEIVE_BUFSIZE;
  CacheP_wb((void *)trans.buf, trans.count, CacheP_TYPE_ALL);
  transferOK = UART_write(gUartHandle[CONFIG_UART_CONSOLE], &trans);
  APP_UART_ASSERT_ON_FAILURE(transferOK, trans);

  /* Wait for write completion */
  SemaphoreP_pend(&gUartWriteDoneSem, SystemP_WAIT_FOREVER);
  DebugP_assert(gNumBytesWritten == APP_UART_RECEIVE_BUFSIZE);

  /* Send exit string */
  gNumBytesWritten = 0U;
  trans.buf = &gUartBuffer[0U];
  strncpy(trans.buf, "\r\nAll tests have passed!!\r\n", APP_UART_BUFSIZE);
  trans.count = strlen(trans.buf);
  CacheP_wb((void *)trans.buf, trans.count, CacheP_TYPE_ALL);
  transferOK = UART_write(gUartHandle[CONFIG_UART_CONSOLE], &trans);
  APP_UART_ASSERT_ON_FAILURE(transferOK, trans);

  /* Wait for write completion */
  SemaphoreP_pend(&gUartWriteDoneSem, SystemP_WAIT_FOREVER);
  DebugP_assert(gNumBytesWritten == strlen(trans.buf));

  DebugP_log("All tests have passed!!\r\n");

  Board_driversClose();
  Drivers_close();

  return;
}


void uart_echo_write_callback(UART_Handle handle, UART_Transaction *trans)
{
    DebugP_assertNoLog(UART_TRANSFER_STATUS_SUCCESS == trans->status);
    gNumBytesWritten = trans->count;
    SemaphoreP_post(&gUartWriteDoneSem);

    return;
}

void uart_echo_read_callback(UART_Handle handle, UART_Transaction *trans)
{
    DebugP_assertNoLog(UART_TRANSFER_STATUS_SUCCESS == trans->status);
    gNumBytesRead = trans->count;
    SemaphoreP_post(&gUartReadDoneSem);

    return;
}

If anyone knows how I can resolve this issue, please help me.

Thank you!