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USART->DMA using STM32F3 Discovery

Question asked by hzcodec on Sep 20, 2016
Latest reply on Sep 21, 2016 by hzcodec
Hi,
I've been struggling to get interrupt for DMA working. I got it working for USART interrupt.

I'm configuring for USART1 and DMA1_Channel5.
My problem is that I don't get an interrupt for the DMA.

So is there something I miss during the configuration?
Regards

main.c
void USART1_IRQHandler(void)
{
}
void DMA1_Channel5_IRQHandler(void)
{
    // do something
}
main(void)
{
    NVIC_SetPriorityGrouping(PRIORITY_GROUP);
    NVIC_SetPriority(DMA1_Channel5_IRQn, NVIC_EncodePriority(PRIORITY_GROUP, 1, 1));   // DMA
    NVIC_SetPriority(USART1_IRQn, NVIC_EncodePriority(PRIORITY_GROUP, 2, 0));           // USART1
    NVIC_SetPriority(SysTick_IRQn, NVIC_EncodePriority(PRIORITY_GROUP, 2, 2));           // SysTick
    bsp_init();
    while (1)
    {
        // just loop 4 ever :-)
    }
}


bsp.c
void GPIO_Usart_1_Configuaration(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    // enable USART clocks
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

    // setup port A
    GPIO_InitStructure.GPIO_Mode  = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_Pin   = GPIO_Pin_9 |  // USART1_TX
                                    GPIO_Pin_10;  // USART1_RX

    GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_7);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_7);

    GPIO_Init(GPIOA, &GPIO_InitStructure);

    // setup USART1
    USART_InitTypeDef USART_InitStructure;
    USART_ClockInitTypeDef USART_ClockInitStructure;

    // setu up USART1_ClockInitStruct member with its default value
    USART_ClockStructInit(&USART_ClockInitStructure);
    USART_ClockInit(USART1, &USART_ClockInitStructure);
    
    USART_InitStructure.USART_BaudRate            = BAUDRATE_9600;
    USART_InitStructure.USART_WordLength          = USART_WordLength_8b;
    USART_InitStructure.USART_StopBits            = USART_StopBits_1;
    USART_InitStructure.USART_Parity              = USART_Parity_No;
    USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStructure.USART_Mode                = USART_Mode_Rx | USART_Mode_Tx;

    USART_Init(USART1, &USART_InitStructure);

    // enable DMA interface for RX
    USART_DMACmd(USART1, USART_DMAReq_Rx, ENABLE);  // USART_CR3, 0x4001 3808

    // enable USART1 port
    USART_Cmd(USART1, ENABLE);

    // enable CM, RXNE interrupt
    USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);

    // enable USART1 global interrupt
    NVIC_EnableIRQ(USART1_IRQn);
}


void GPIO_Dma_1_Configuaration(void)
{
    DMA_InitTypeDef DMA_InitStructure;

    // enable DMA clocks
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);

    /* DMA2 channel5 configuration */
    DMA_DeInit(DMA1_Channel5);
    DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&USART1->RDR;          // DMA_CPAR, 0x4002 0060
    DMA_InitStructure.DMA_MemoryBaseAddr     = 0x00000000;                      // DMA_CMAR, 0x4002 0064
    DMA_InitStructure.DMA_DIR                = DMA_DIR_PeripheralSRC;
    DMA_InitStructure.DMA_BufferSize         = RX_BUFFER_SIZE;                  // DMA_CNDTR, 0x4002 005C
    DMA_InitStructure.DMA_PeripheralInc      = DMA_PeripheralInc_Disable;
    DMA_InitStructure.DMA_MemoryInc          = DMA_MemoryInc_Enable;
    DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
    DMA_InitStructure.DMA_MemoryDataSize     = DMA_MemoryDataSize_Byte;
    DMA_InitStructure.DMA_Mode               = DMA_Mode_Circular;
    DMA_InitStructure.DMA_Priority           = DMA_Priority_High;               // DMA_CCR, 0x4002 0058
    DMA_InitStructure.DMA_M2M                = DMA_M2M_Disable;

    DMA_Init(DMA1_Channel5, &DMA_InitStructure);

    // enable DMA interrupt
    NVIC_EnableIRQ(DMA1_Channel5_IRQn);

    // enable transfer complete interrupt
    DMA_ITConfig(DMA1_Channel5, DMA_IT_TC, ENABLE);

    // enable DMA1 channel5
    DMA_Cmd(DMA1_Channel5, ENABLE);
}

// initialize clocks and GPIO ports
void bsp_init(void)
{
    GPIO_Usart_1_Configuaration();
    GPIO_Dma_1_Configuaration();
}

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