串口初始化USART1_Init();

串口初始化USART1_Init();

//USART1_Init();			/* 串口初始化，用于调试 */

void USART1_Init(void)
{
    //定义配置结构体
	GPIO_InitTypeDef	GPIO_InitStructure;
	USART_InitTypeDef	USART_InitStructure;
	NVIC_InitTypeDef	NVIC_InitStructure;

    //时钟源启动
	RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE);

    //PA9配置
	GPIO_InitStructure.GPIO_Pin	= GPIO_Pin_9;
	GPIO_InitStructure.GPIO_Mode	= GPIO_Mode_AF_PP;
	GPIO_InitStructure.GPIO_Speed	= GPIO_Speed_50MHz;
	GPIO_Init(GPIOA, &GPIO_InitStructure);
	//PA10配置，用了PA9的GPIO_InitStructure通用数据
	GPIO_InitStructure.GPIO_Pin	= GPIO_Pin_10;
	GPIO_InitStructure.GPIO_Mode	= GPIO_Mode_IN_FLOATING;
	GPIO_Init(GPIOA, &GPIO_InitStructure);

	USART_InitStructure.USART_BaudRate		= 115200;//波特率
	USART_InitStructure.USART_WordLength	= USART_WordLength_8b;//数据位8
	USART_InitStructure.USART_StopBits		= USART_StopBits_1;//停止位1
	USART_InitStructure.USART_Parity		= USART_Parity_No;//校验位无
	USART_InitStructure.USART_HardwareFlowControl	= USART_HardwareFlowControl_None;//流控制无
	USART_InitStructure.USART_Mode			= USART_Mode_Rx | USART_Mode_Tx;//串口模式
	USART_Init(USART1, &USART_InitStructure);//串口初始化
	USART_Cmd(USART1, ENABLE);//串口使能
	USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);//串口中断使能

	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_4);//中断优先级组配置
	NVIC_InitStructure.NVIC_IRQChannel			= USART1_IRQn;//中断请求通道选择
	NVIC_InitStructure.NVIC_IRQChannelSubPriority		= 0; //抢占优先级
	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority	= 10;//相应优先级
	NVIC_InitStructure.NVIC_IRQChannelCmd			= ENABLE;//中断请求通道使能
	NVIC_Init(&NVIC_InitStructure);//中断初始化
	
	USART1->SR;//读取SR寄存器
}

SR串口状态寄存器：