STM32F4 串口（DMA发送接收方式）代码例程

#include "stm32f4xx.h" #include "UART1.h" #include "String.h" #define BUFFER_SIZE1 50 static DMA_InitTypeDef DMA_InitStructureTx; static DMA_InitTypeDef DMA_InitStructureRx; static char TxBuffer[BUFFER_SIZE1]; static char RxBuffer[BUFFER_SIZE1]; __IO u16 RxCount = 0; void USART1_Init(void) //串口初始化 { NVIC_InitTypeDef NVIC_InitStructure; GPIO_InitTypeDef GPIO_InitStructure; USART_InitTypeDef USART_InitStructure; RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE); RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA | RCC_AHB1Periph_DMA2, ENABLE); GPIO_PinAFConfig(GPIOA, GPIO_PinSource9, GPIO_AF_USART1); GPIO_PinAFConfig(GPIOA, GPIO_PinSource10, GPIO_AF_USART1); GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; GPIO_Init(GPIOA, &GPIO_InitStructure); GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; GPIO_Init(GPIOA, &GPIO_InitStructure); USART_InitStructure.USART_BaudRate = 115200; 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); USART_DMACmd(USART1, USART_DMAReq_Tx | USART_DMAReq_Rx, ENABLE); DMA_InitStructureTx.DMA_BufferSize = BUFFER_SIZE1 ; DMA_InitStructureTx.DMA_FIFOMode = DMA_FIFOMode_Disable ; DMA_InitStructureTx.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull ; DMA_InitStructureTx.DMA_MemoryBurst = DMA_MemoryBurst_Single ; DMA_InitStructureTx.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; DMA_InitStructureTx.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructureTx.DMA_Mode = DMA_Mode_Normal; DMA_InitStructureTx.DMA_PeripheralBaseAddr =(uint32_t) (&(USART1->DR)) ; DMA_InitStructureTx.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_InitStructureTx.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; DMA_InitStructureTx.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructureTx.DMA_Priority = DMA_Priority_High; /* Configure TX DMA */ DMA_InitStructureTx.DMA_Channel = DMA_Channel_4 ; DMA_InitStructureTx.DMA_DIR = DMA_DIR_MemoryToPeripheral ; DMA_InitStructureTx.DMA_Memory0BaseAddr =(uint32_t)TxBuffer ; DMA_Init(DMA2_Stream7,&DMA_InitStructureTx); DMA_ITConfig(DMA2_Stream7, DMA_IT_TC, ENABLE); DMA_InitStructureRx.DMA_BufferSize = BUFFER_SIZE1 ; DMA_InitStructureRx.DMA_FIFOMode = DMA_FIFOMode_Disable ; DMA_InitStructureRx.DMA_FIFOThreshold = DMA_FIFOThreshold_1QuarterFull ; DMA_InitStructureRx.DMA_MemoryBurst = DMA_MemoryBurst_Single ; DMA_InitStructureRx.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; DMA_InitStructureRx.DMA_MemoryInc = DMA_MemoryInc_Enable; DMA_InitStructureRx.DMA_Mode = DMA_Mode_Normal; DMA_InitStructureRx.DMA_PeripheralBaseAddr =(uint32_t) (&(USART1->DR)) ; DMA_InitStructureRx.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; DMA_InitStructureRx.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; DMA_InitStructureRx.DMA_PeripheralInc = DMA_PeripheralInc_Disable; DMA_InitStructureRx.DMA_Priority = DMA_Priority_High; /* Configure RX DMA */ DMA_InitStructureRx.DMA_Channel = DMA_Channel_4 ; DMA_InitStructureRx.DMA_DIR = DMA_DIR_PeripheralToMemory ; DMA_InitStructureRx.DMA_Memory0BaseAddr =(uint32_t)RxBuffer ; DMA_Init(DMA2_Stream5,&DMA_InitStructureRx); DMA_Cmd(DMA2_Stream5,ENABLE); NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; NVIC_Init(&NVIC_InitStructure); USART_ITConfig(USART1, USART_IT_IDLE,ENABLE); USART_Cmd(USART1, ENABLE); } void USART1_IRQHandler(void) { if(USART_GetITStatus(USART1, USART_IT_IDLE) != RESET) { USART_ReceiveData(USART1); RxCount = BUFFER_SIZE1 - DMA_GetCurrDataCounter(DMA2_Stream5); DMA_Cmd(DMA2_Stream5, DISABLE); DMA_DeInit(DMA2_Stream5); DMA_InitStructureRx.DMA_Memory0BaseAddr = (uint32_t)RxBuffer; DMA_InitStructureRx.DMA_BufferSize = BUFFER_SIZE1; DMA_Init(DMA2_Stream5, &DMA_InitStructureRx); DMA_Cmd(DMA2_Stream5, ENABLE); } USART_ClearITPendingBit(USART1, USART_IT_IDLE | USART_IT_PE | USART_IT_FE | USART_IT_NE); } u8 USART1_RecBuffer(u8 *buffer) { u16 i; i = RxCount; RxCount = 0; memcpy(buffer, RxBuffer, i); return i; } u8 USART1_SendBuffer(u8 *buffer, u16 n) { memcpy(TxBuffer, buffer, n); DMA_Cmd(DMA2_Stream7, DISABLE); DMA_DeInit(DMA2_Stream7); DMA_InitStructureTx.DMA_Memory0BaseAddr = (uint32_t)TxBuffer; DMA_InitStructureTx.DMA_BufferSize = n; DMA_Init(DMA2_Stream7, &DMA_InitStructureTx); DMA_ITConfig(DMA2_Stream7, DMA_IT_TC, ENABLE); DMA_Cmd(DMA2_Stream7, ENABLE); return 0; }