1.UART初始化函数
void uart_init(u32 bound){
GPIO_InitTypeDef GPIO_InitStructure; //GPIO端口设置
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA,ENABLE); //使能GPIOA时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);//使能USART1时钟
GPIO_PinAFConfig(GPIOA,GPIO_PinSource9,GPIO_AF_USART1); //GPIOA9复用为USART1 //串口1对应引脚复用映射
GPIO_PinAFConfig(GPIOA,GPIO_PinSource10,GPIO_AF_USART1); //GPIOA10复用为USART1
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10; //GPIOA9与GPIOA10 //USART1端口配置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; //速度50MHz
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; //推挽复用输出
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP; //上拉
GPIO_Init(GPIOA,&GPIO_InitStructure); //初始化PA9,PA10
USART_InitStructure.USART_BaudRate = bound;//波特率设置 //USART1 初始化设置
USART_InitStructure.USART_WordLength = USART_WordLength_8b;//字长为8位数据格式
USART_InitStructure.USART_StopBits = USART_StopBits_1;//一个停止位
USART_InitStructure.USART_Parity = USART_Parity_No;//无奇偶校验位
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;//无硬件数据流控制
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx; //收发模式
USART_Init(USART1, &USART_InitStructure); //初始化串口1
USART_Cmd(USART1, ENABLE); //使能串口1
USART_ClearFlag(USART1, USART_FLAG_TC);
USART_DMACmd(USART1,USART_DMAReq_Rx,ENABLE); //使能串口1的DMA发送
MYDMA_Config(DMA2_Stream5,DMA_Channel_4,(u32)&USART1->DR,(u32)DmaDataReadBuffUart1,DMA_DATA_READ_LEN);
}
2.DMA配置函数
void MYDMA_Config(DMA_Stream_TypeDef *DMA_Streamx,u32 chx,u32 par,u32 mar,u16 ndtr)
{
NVIC_InitTypeDef NVIC_InitStructure;
DMA_InitTypeDef DMA_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA2,ENABLE); //DMA2时钟使能
DMA_DeInit(DMA_Streamx); // 作用主要是为了清除 数据传输完成标志位TCIF5
while (DMA_GetCmdStatus(DMA_Streamx) != DISABLE){}//等待DMA可配置
DMA_InitStructure.DMA_Channel = chx; //通道选择
DMA_InitStructure.DMA_PeripheralBaseAddr = par;//DMA外设地址
DMA_InitStructure.DMA_Memory0BaseAddr = mar;//DMA 存储器0地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory; //方向:从串口到内存
DMA_InitStructure.DMA_BufferSize = ndtr;//数据传输量
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;//外设非增量模式
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;//存储器增量模式
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;//外设数据长度:8位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte;//存储器数据长度:8位
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; // 使用普通模式
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;//中等优先级
DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; //FIFO功能失能
DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_Full;
DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single;//存储器突发单次传输
DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single;//外设突发单次传输
DMA_Init(DMA_Streamx, &DMA_InitStructure);//初始化DMA Stream
DMA_Cmd(DMA2_Stream5, ENABLE); //开启DMA传输
}
2.帧判断
该函数放到主循环实时检测
u8 StartReceiveNum = 0;
u8 CurrentReceiveNum = 0;
u8 DMAReceiveData_Deal(void)
{
u8 i = 0;
if(GetDMAReceiveTimeStates() == false){
StartReceiveNum = DMA_DATA_READ_LEN - DMA_GetCurrDataCounter(DMA2_Stream5);
if( StartReceiveNum ){
DMAReceiveTimeInit(DMA_RECEIVE_TIMEOUT);
}
}
//超时检测
if( GetDMAReceiveTimeStates() && SysRunTimeOut() )
{
CurrentReceiveNum = DMA_DATA_READ_LEN - DMA_GetCurrDataCounter(DMA2_Strea
if(CurrentReceiveNum == StartReceiveNum){
//进入处理函数
for(i = 0; i < CurrentReceiveNum; i++){
CommandDataType_push(DmaDataReadBuff[i]);
Uart1SendData(DmaDataReadBuff[i]);
}
StartReceiveNum = 0;
CurrentReceiveNum = 0;
DMAReceiveTimeDisable();
//DMA模块相关初始化
DMA_Cmd(DMA2_Stream5, DISABLE); //关闭DMA,防止处理其间有数据
MYDMA_Config(DMA2_Stream5,DMA_Channel_4,(u32)&USART1->DR,(u32)DmaDataReadBuff,DMA_DATA_READ_LEN);
DMA_Cmd(DMA2_Stream5, ENABLE); //打开DMA,
DMA_ClearFlag(DMA2_Stream5,DMA_FLAG_TCIF5);//清除DMA2_Steam7传输完成标志
}else{
StartReceiveNum = CurrentReceiveNum;
DMAReceiveTimeInit(DMA_RECEIVE_TIMEOUT);
}
}
}
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