DMA uart XferCpltCallback problem

[Tanaz Javanmardi]

Posted on June 09, 2018 at 08:55

Hi

I use DMA in Interrupt mode to receive data from UART Periph to memory. data is transfered (my destination memory is occupied correctly)but my DMAReceiptComplete() callback function is never called.

/*--------------------------------------------------------------------------main.c------------------------------------------------------------------------*/

/* Includes ------------------------------------------------------------------*/

&sharpinclude 'stm32f1xx_hal.h'&sharpinclude <myboard_hal_bsp.h>&sharpinclude 'string.h'/* Private variables ---------------------------------------------------------*/extern UART_HandleTypeDef huart2;extern UART_HandleTypeDef huart1;DMA_HandleTypeDef hdma_usart1_rx;DMA_HandleTypeDef hdma_usart2_tx;char *msg = 'HI Hello STM32 Lovers! This message is transferred in DMA Mode.\r\n';uint8_t buf[2] = '';void DMAReceiptComplete(DMA_HandleTypeDef *hdma);

int main(void){

    HAL_Init();    MyBoard_BSP_Init();

    //USART1

    hdma_usart1_rx.Instance = DMA1_Channel5;    hdma_usart1_rx.Init.Direction = DMA_PERIPH_TO_MEMORY;    hdma_usart1_rx.Init.PeriphInc = DMA_PINC_DISABLE;    hdma_usart1_rx.Init.MemInc = DMA_MINC_ENABLE;    hdma_usart1_rx.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;    hdma_usart1_rx.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;    hdma_usart1_rx.Init.Mode = DMA_CIRCULAR;    hdma_usart1_rx.Init.Priority = DMA_PRIORITY_VERY_HIGH;    hdma_usart1_rx.XferCpltCallback = &DMAReceiptComplete;

    HAL_DMA_Init(&hdma_usart1_rx);

    /* DMA interrupt init */    HAL_NVIC_SetPriority(DMA1_Channel5_IRQn, 0, 0);    HAL_NVIC_EnableIRQ(DMA1_Channel5_IRQn);    HAL_DMA_Start_IT(&hdma_usart1_rx, (uint32_t)&huart1.Instance->DR, (uint32_t)buf, 2);    //Enable UART in DMA mode    huart1.Instance->CR3 |= USART_CR3_DMAR;

    //USART2

    hdma_usart2_tx.Instance = DMA1_Channel7;    hdma_usart2_tx.Init.Direction = DMA_MEMORY_TO_PERIPH;    hdma_usart2_tx.Init.PeriphInc = DMA_PINC_DISABLE;    hdma_usart2_tx.Init.MemInc = DMA_MINC_DISABLE;    hdma_usart2_tx.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD;    hdma_usart2_tx.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD;    hdma_usart2_tx.Init.Mode = DMA_NORMAL;    hdma_usart2_tx.Init.Priority = DMA_PRIORITY_LOW;    HAL_DMA_Init(&hdma_usart2_tx);    __HAL_LINKDMA(&huart2, hdmatx, hdma_usart2_tx);

    /* DMA interrupt init */

    HAL_NVIC_SetPriority(DMA1_Channel7_IRQn, 0, 0);    HAL_NVIC_EnableIRQ(DMA1_Channel7_IRQn);    /* Peripheral interrupt init */    HAL_NVIC_SetPriority(USART2_IRQn, 0, 0);    HAL_NVIC_EnableIRQ(USART2_IRQn);    //Enable UART in DMA mode ( receive or transmit DMAR DMAT)    huart2.Instance->CR3 |= USART_CR3_DMAT;    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_SET);

    while(1);

     return 0;}

void DMAReceiptComplete(DMA_HandleTypeDef *hdma) {

    HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5, GPIO_PIN_RESET);    if (hdma->Instance == DMA1_Channel5){ //now we should enable usart2 i think        HAL_UART_Transmit_DMA(&huart2, (uint8_t*)buf, 2);

    }

}

void DMA1_Channel5_IRQHandler(void){

    HAL_DMA_IRQHandler(&hdma_usart1_rx);}

void USART1_IRQHandler (void){

    HAL_UART_IRQHandler(&huart1);}

void DMA1_Channel7_IRQHandler(void){

    HAL_DMA_IRQHandler(&hdma_usart2_tx);}

void USART2_IRQHandler (void){

    HAL_UART_IRQHandler(&huart2);}void HAL_UART_TxCpltCallback(UART_HandleTypeDef *huart){    ;}

Is it a bug or I made mistake somewhere?

#dma-uart #xfercpltcallback

[T J]

Posted on June 11, 2018 at 01:10

did you fix it ?

did you use the cube ?

I use the Uart  DMA in Circular mode.

I just calculate the buffer size from the DMA counter.

[Tanaz Javanmardi]

Posted on June 11, 2018 at 10:47

no I haven't fixed it.

yes I used cube

the problem is with dmauart1_rx , I used it in circular mode too. but

what's the point?

[T J]

Posted on June 11, 2018 at 10:56

why do you need DMAReceiptComplete() ?

I poll this function every mS,   RxBufSize = readableU1();  // unread length

void initUart1RxDMABuffer(void) {

    if (HAL_UART_Receive_DMA(&huart1, (uint8_t *)Usart1RxDMABuffer, U1RxBufSize) != HAL_OK)          printf(string, 'initUart1RxDMABuffer Failed\n');    else        printf(string, 'initUart1RxDMABuffer OK!\n');}

char readableU1(void) {

    U1RxBufferPtrIN =  U1RxBufSize - huart1.hdmarx->Instance->CNDTR;    return U1RxBufferPtrIN - U1RxBufferPtrOUT;  // length of unread characters}

char getc1(void) {

    char Rxbyte = Usart1RxDMABuffer[U1RxBufferPtrOUT++];    if (U1RxBufferPtrOUT >= U1RxBufSize) U1RxBufferPtrOUT = 0;    return Rxbyte;}