#include "stdio.h"

void usart_Configuration(void)
{ GPIO_InitTypeDef GPIO_InitStructure;
 USART_InitTypeDef USART_InitStructure;
 NVIC_InitTypeDef NVIC_InitStructure;
  USART_ClockInitTypeDef  USART_ClockInitStructure;
//////////////////////////////////////////////////////////////////
 //
 USART_ClockInit(USART1, &USART_ClockInitStructure);
 
 USART_InitStructure.USART_BaudRate = 115200;
 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);
 USART_ITConfig(USART1,USART_IT_TXE,ENABLE);
 
 USART_ClearFlag(USART1, USART_FLAG_TC);    
}

int fputc(int ch, FILE *f)
{
 
 
 USART_SendData(USART1,(uint8_t) ch);

 
 while (USART_GetFlagStatus(USART1, USART_FLAG_TC) == RESET)
 {
 
 }

 return ch;
}

int fgetc(FILE *f)
{
 
 while (USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET)
 {}
 return (int)USART_ReceiveData(USART1);
}

void USART1_IRQHandler(void)
{  u16 RxBuf;
  if(USART_GetFlagStatus(USART1,USART_IT_RXNE)==SET)
  {             
   RxBuf=USART_ReceiveData(USART1);
//   printf("%d",RxBuf);
//   printf("   ");
   switch(RxBuf)
  {          //
    case 1: printf("1 ");printf("%d",255);break;//对方发送是1
    case 2: printf("2 ");printf("%d",255);break;//对方发送是2
    case 3: printf("3 ");printf("%d",255);break;//对方发送是3
    default: printf("4 ");printf("%d",255);break;
   }
  }
  if(USART_GetITStatus(USART1, USART_IT_TXE) != RESET)                   //这段是为了避免STM32 USART 第一个字节发不出去的BUG
  {
     USART_ITConfig(USART1, USART_IT_TXE, DISABLE);          //禁止发缓冲器空中断，
  } 
}