stm32f103c8t6 串口空闲中断DMA接收问题

ccwinner · 发表于 2020-2-10 23:34:50

Usart1-Rx作为外设，DMA接收到内存Buf，设置串口空闲中断，结果是空闲中断后得到数据没有按照一个Byte拆包，很纳闷是怎么回事：比如串口助手发送数据A1B2C3D4,中断后接收到数据是Buf【0】=D4C3B2A1;DMA初始化中设置数据传输是8位，不应该是 Buf【0】=A1,Buf【1】=B2,Buf【2】=C3,Buf【3】=D4;一个Byte数据一个地址递增吗？

Usart1初始化：
//GPIO端口设置
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1|RCC_APB2Periph_GPIOA, ENABLE); //使能USART1，GPIOA时钟

//USART1_TX GPIOA.9
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; //PA.9
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.9

//USART1_RX    GPIOA.10初始化
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;//PA10
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;//浮空输入
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIOA.10

//Usart1 NVIC 配置
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=3 ;//抢占优先级3
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //子优先级3
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道使能
NVIC_Init(&NVIC_InitStructure); //根据指定的参数初始化VIC寄存器

//USART 初始化设置

USART_InitStructure.USART_BaudRate = bound;//串口波特率
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_ITConfig(USART1, USART_IT_RXNE, ENABLE); //开启串口接受中断
USART_ITConfig(USART1,USART_IT_IDLE,ENABLE);
USART_Cmd(USART1, ENABLE);                     //使能串口1

//*********************************************************************************
dma初始化：
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE); //使能DMA传输
DMA_DeInit(DMA1_Channel5);    //将DMA的通道1寄存器重设为缺省值
DMA1_MEM_LEN=100;
DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t)&USART1->DR;    //DMA外设基地址
DMA_InitStructure.DMA_MemoryBaseAddr =(uint32_t)Usart1RxBuf;    //DMA内存基地址
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;    //数据传输方向，从内存读取发送到外设
DMA_InitStructure.DMA_BufferSize = 100;    //DMA通道的DMA缓存的大小
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;    //外设地址寄存器不变
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;      //内存地址寄存器递增
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; //数据宽度为8位
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; //数据宽度为8位
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;    //工作在正常模式
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium; //DMA通道 x拥有中优先级
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;    //DMA通道x没有设置为内存到内存传输
DMA_Init(DMA1_Channel5, &DMA_InitStructure);    //根据DMA_InitStruct中指定的参数初始化DMA的通道USART1_Tx_DMA_Channel所标识的寄存器
USART_DMACmd(USART1,USART_DMAReq_Rx,ENABLE);
DMA_Cmd(DMA1_Channel5,ENABLE);

//*********************************************************************************
IDLE中断：
uint8_t Res;
if(USART_GetITStatus(USART1, USART_IT_IDLE) != RESET)  //
{
// USART_ClearFlag(USART1,USART_FLAG_IDLE);
Res=USART1->SR;
Res=USART1->DR;
DMA_Cmd(DMA1_Channel5,DISABLE);
DMA_SetCurrDataCounter(DMA1_Channel5,100);
DMA_Cmd(DMA1_Channel5,ENABLE);

memcpy(Usart1RxData,Usart1RxBuf,100);
memset(Usart1RxBuf,0x00,100);
}