串口配置

void My USART1_Init(void)
	{	
		NVIC_InitTypeDef NVIC_InitStruct;
		GPIO_InitTypeDef GPIO_InitStrue; 
		USART_InitTypeDef USART_InitStruct;
		
		
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
		GPIO_InitStrue.GPIO_Pin=GPIO_Pin_9;
 		GPIO_InitStrue.GPIO_Mode=GPIO_Mode_AF_PP;
		GPIO_InitStrue.GPIO_Speed=GPIO_Speed_10MHz;
		GPIO_Init(GPIOA,&GPIO_InitStrue);
		
		GPIO_InitTypeDef GPIO_InitStrue; 
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);
		RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,ENABLE);
		GPIO_InitStrue.GPIO_Pin=GPIO_Pin_10;
 		GPIO_InitStrue.GPIO_Mode=GPIO_Mode_IN_FLOATING;
		GPIO_InitStrue.GPIO_Speed=GPIO_Speed_10MHz;
		GPIO_Init(GPIOA,&GPIO_InitStrue);
		
		USART_InitStruct.USART_BaudRate=115200;
		USART_InitS0truct.USART_WordLength=USART_WordLength_8b;
		USART_InitStruct.USART_Parity=USART_Parity_No;
		USART_InitStruct.USART_StopBits=USART_StopBits_1;
		USART_InitStruct.USART_Mode=USART_Mode_Rx|USART_Mode_Tx;
		USART_Init(USART1,&USART_InitStruct)
		
		USART_Cmd(USART1,ENABLE);
		USART_ITConfig(USART1,USART_IT_RXNE,ENABLE);
		USART_InitStruct.NVIC_IRQChannel=USART1_IRQn;
		USART_InitStruct.NVIC_IRQChannelPreemptionPriority=1;
		USART_InitStruct.NVIC_IRQChannelSubPriority=1;
		USART_InitStruct.NVIC_IRQChannelCmd=ENABLE;
		NVIC_Init(&NVIC_InitStruct);
	
	}

	void USART1_IRQHandler(void)
	{
		int res;
		if(USART_GetITStatus(USART1,USART_IT_RXNE))
			{
				res=USART_ReceiveData(USART1);
				USART_SendData(USART1,res);
			}
	}