Posted on March 06, 2015 at 14:21Hi.
I am a newbe in STM32 microcontroles. I have problems with starting the DMA transfer to UART.
This is my init for UART.
/*
* Helpers for DMA configuration
*/
static UART_HandleTypeDef *hRS232_handle=&RS232_handle;
static DMA_HandleTypeDef RS232_RX_DMA_handle;
static DMA_HandleTypeDef RS232_TX_DMA_handle;
/*
* GPIO UART pin configuration
*/
/*
* GPIO Clock enable
*/
__GPIOA_CLK_ENABLE();
/*
* Configure GPIO RX & TX Pins.
* For UART2 TX - PA2
* For UART2 RX - PA3
*/
GPIO_InitTypeDef GPIO_InitStruct;
GPIO_InitStruct.Pin = GPIO_PIN_2 | GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_PULLUP;
GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF1_USART2;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/*
* USART port clock enable
*/
__USART2_CLK_ENABLE();
/*
* Configure USART parameters
*/
RS232_handle.Instance = USART2;
RS232_handle.Init.BaudRate = 300;
RS232_handle.Init.WordLength = USART_WORDLENGTH_8B;
RS232_handle.Init.StopBits = USART_STOPBITS_1;
RS232_handle.Init.Parity = USART_PARITY_NONE;
RS232_handle.Init.Mode = USART_MODE_TX_RX;
RS232_handle.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
/*
* Configure DMA Clock
*/
__DMA1_CLK_ENABLE();
/*
* Configure DMA RX Channel
*/
RS232_RX_DMA_handle.Instance = DMA1_Channel4;
RS232_RX_DMA_handle.Init.Direction = DMA_PERIPH_TO_MEMORY;
RS232_RX_DMA_handle.Init.PeriphInc = DMA_PINC_DISABLE;
RS232_RX_DMA_handle.Init.MemInc = DMA_MINC_ENABLE;
RS232_RX_DMA_handle.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
RS232_RX_DMA_handle.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
RS232_RX_DMA_handle.Init.Mode = DMA_NORMAL;
RS232_RX_DMA_handle.Init.Priority = DMA_PRIORITY_LOW;
HAL_DMA_Init(&RS232_RX_DMA_handle);
__HAL_LINKDMA(hRS232_handle, hdmarx, RS232_RX_DMA_handle);
/*
* Interrupt for DMA TX channel.
*/
HAL_NVIC_SetPriority(DMA1_Channel4_5_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(DMA1_Channel4_5_IRQn);
/*
* Configure DMA TX Channel
*/
RS232_TX_DMA_handle.Instance = DMA1_Channel5;
RS232_TX_DMA_handle.Init.Direction = DMA_MEMORY_TO_PERIPH;
RS232_TX_DMA_handle.Init.PeriphInc = DMA_PINC_DISABLE;
RS232_TX_DMA_handle.Init.MemInc = DMA_MINC_ENABLE;
RS232_TX_DMA_handle.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
RS232_TX_DMA_handle.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
RS232_TX_DMA_handle.Init.Mode = DMA_NORMAL;
RS232_TX_DMA_handle.Init.Priority = DMA_PRIORITY_HIGH;
HAL_DMA_Init(&RS232_TX_DMA_handle);
__HAL_LINKDMA(hRS232_handle, hdmatx, RS232_TX_DMA_handle);
/*
* Interrupt for DMA TX channel.
*/
HAL_NVIC_SetPriority(DMA1_Channel4_5_IRQn, 0, 1);
HAL_NVIC_EnableIRQ(DMA1_Channel4_5_IRQn);
/*
* Configure Interrupt for UART
*/
HAL_NVIC_SetPriority(USART2_IRQn, 0, 1);
HAL_NVIC_EnableIRQ(USART2_IRQn);
/*
* Initialize USART
*/
HAL_UART_Init(&RS232_handle);
For DMA IRQ:
void DMA1_Channel4_5_IRQHandler(void){
HAL_DMA_IRQHandler(RS232_handle.hdmatx);
HAL_DMA_IRQHandler(RS232_handle.hdmarx);
}
Everything works fine when I am using the Polling mode - HAL_UART_Transmit
But when I am trying to use HAL_UART_Transmit_DMA, I can not see any transfer form the UART.
When I try to use breakpoint on IRQ, the breakpoint never stops the program.
