USART->DMA using STM32F3 Discovery

[heinz]

Posted on September 20, 2016 at 21:49

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(); } #stm32

[Tesla DeLorean]

Posted on September 21, 2016 at 00:35

Zero isn't going to be a viable buffer address here.

You should provide enough code for this to compile and be testable, a bunch of definitions missing.

[heinz]

Posted on September 21, 2016 at 09:00

About the code, yes I just cut out what I thought was the important stuff.

Nevertheless I changed my buffer address to:

DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)rx_buffer;

I have a declaration further up in the code:

char rx_buffer[2];

And now I can see that I get a DMA interrupt. At least one step ahead. Thank You Clive1.