void USART1_IRQHandler(void)
{
//static u8 k;
USART_ClearFlag(USART1,USART_FLAG_TC);//清除USARTx的待处理标志位
if(USART_GetITStatus(USART1,USART_IT_RXNE)!=Bit_RESET)
{
USART_ReceiveData(USART1);
USART_SendData(USART2,USART_ReceiveData(USART1));
while(USART_GetFlagStatus(USART1,USART_IT_RXNE)!=RESET);
}
}