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#include "usart.h"
#include <stdarg.h>
void USART1_Config(void)
{
   GPIO_InitTypeDef GPIO_InitStructure;
 USART_InitTypeDef USART_InitStructure;
 NVIC_InitTypeDef NVIC_InitStructure;//中断默认参数

 RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);
 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);

 GPIO_InitStructure.GPIO_Pin=GPIO_Pin_10;
 GPIO_InitStructure.GPIO_Mode=GPIO_Mode_IN_FLOATING;
 GPIO_Init(GPIOA,&GPIO_InitStructure);

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

 USART_InitStructure.USART_BaudRate=9600;
 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_Init(USART1, &USART_InitStructure);      

 USART_Cmd(USART1, ENABLE);
 USART_ITConfig(USART1, USART_IT_RXNE, ENABLE);
}