STM32的串口采用DMA方式发送数据测试

STM32的串口采用DMA方式发送数据测试

文博客链接:http://blog.csdn.net/jdh99,作者:jdh,转载请注明.

环境：

主机:WIN7

开发环境:MDK4.23

MCU:STM32F103CBT6

源代码:

配置:

//---------------------串口功能配置---------------------
//打开串口对应的外设时钟  
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 , ENABLE);   
//启动DMA时钟
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
//DMA发送中断设置
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel4_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 2;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
//DMA1通道4配置
DMA_DeInit(DMA1_Channel4);
//外设地址
DMA_InitStructure.DMA_PeripheralBaseAddr = (u32)(&USART1->DR);
//内存地址
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)Uart_Send_Buffer;
//dma传输方向单向
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST;
//设置DMA在传输时缓冲区的长度
DMA_InitStructure.DMA_BufferSize = 100;
//设置DMA的外设递增模式，一个外设
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
//设置DMA的内存递增模式
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
//外设数据字长
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
//内存数据字长
DMA_InitStructure.DMA_MemoryDataSize = DMA_PeripheralDataSize_Byte;
//设置DMA的传输模式
DMA_InitStructure.DMA_Mode = DMA_Mode_Normal;
//设置DMA的优先级别
DMA_InitStructure.DMA_Priority = DMA_Priority_High;
//设置DMA的2个memory中的变量互相访问
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel4,&DMA_InitStructure);
DMA_ITConfig(DMA1_Channel4,DMA_IT_TC,ENABLE);

//使能通道4
//DMA_Cmd(DMA1_Channel4, ENABLE);

  
//初始化参数  
//USART_InitStructure.USART_BaudRate = DEFAULT_BAUD;  
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_InitStructure.USART_BaudRate = DEFAULT_BAUD; 
//初始化串口 
USART_Init(USART1,&USART_InitStructure);  
//TXE发送中断,TC传输完成中断,RXNE接收中断,PE奇偶错误中断,可以是多个   
USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);  

//配置UART1中断  
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_3);
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;               //通道设置为串口1中断  
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;       //中断占先等级0  
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;              //中断响应优先级0  
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;                 //打开中断  
NVIC_Init(&NVIC_InitStructure);                                 //初始化  

//采用DMA方式发送
USART_DMACmd(USART1,USART_DMAReq_Tx,ENABLE);
//启动串口  
USART_Cmd(USART1, ENABLE);   

//设置IO口时钟      
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);    
//串口1的管脚初始化    
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;                       //管脚9  
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;                //选择GPIO响应速度  
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;                 //复用推挽输出  
GPIO_Init(GPIOA, &GPIO_InitStructure);                          //TX初始化  
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;                      //管脚10  
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;                //选择GPIO响应速度  
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;           //浮空输入  
GPIO_Init(GPIOA, &GPIO_InitStructure);                          //RX初始化                                                      

//设置IO口时钟      
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE);   
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;                       //管脚9  
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;                //选择GPIO响应速度  
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;                 //复用推挽输出  

中断函数：

//串口1DMA方式发送中断
void DMA1_Channel4_IRQHandler(void)
{
	//清除标志位
  	DMA_ClearFlag(DMA1_FLAG_TC4);
	//DMA_ClearITPendingBit(DMA1_FLAG_TC4);
  	//DMA1->IFCR |= DMA1_FLAG_TC4;
	//关闭DMA
	DMA_Cmd(DMA1_Channel4,DISABLE);
 	//DMA1_Channel4->CCR &= ~(1<<0);

	//允许再次发送
	Flag_Uart_Send = 0;
}

发送测试：

//串口DMA发送测试
Uart_Send_Buffer[0] = 1;
Uart_Send_Buffer[1] = 2;
Uart_Send_Buffer[2] = 3;
Uart_Send_Buffer[3] = 4;
Uart_Send_Buffer[4] = 5;
i = 1;
while (1)
{
	//检查串口是否可以发送
	while (Flag_Uart_Send);
	Flag_Uart_Send = 1;
	//设置传输数据长度
	DMA_SetCurrDataCounter(DMA1_Channel4,i);
	//打开DMA
	DMA_Cmd(DMA1_Channel4,ENABLE);
	i++;
	if (i > 5)
	{
		i = 1;
	}
}