求助：串口数据在超级终端的反馈

只看该作者 · 2010-2-6 14:56

从PC键盘上往板子的COM0送字符，并将COM0收到字符再传回超级终端显示，但现在超级终端没显示输入的字符，只显示原来printf的字符？麻烦大家看看哪错了，谢谢
板子是万利的199元的那块板子
程序大致如下：

int main(void)
{
  u16 i=0;

#ifdef DEBUG
  debug();
#endif

  /* System Clocks Configuration */
  RCC_Configuration();

  /* GPIO Configuration */
  GPIO_Configuration();

  /* NVIC configuration */
  NVIC_Configuration();

  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOC, ENABLE);
  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,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);

  USART_Configuration();

  printf("\r\n PLEASE INPUT CHARACTER FROM KEYBOAD \r\n");

  while (1)
  {
if(USART_GetFlagStatus(USART1,USART_IT_RXNE)==SET)
{

i= USART_ReceiveData(USART1);
printf("  %c",i&0xFF);
}
  }
}

void USART_Configuration(void)
{
USART_InitTypeDef USART_InitStructure;
USART_ClockInitTypeDef 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_Even;
  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
  USART_ClockInitStructure.USART_Clock=USART_Clock_Disable;
  USART_ClockInitStructure.USART_CPOL=USART_CPOL_Low;
  USART_ClockInitStructure.USART_CPHA=USART_CPHA_2Edge;
  USART_ClockInitStructure.USART_LastBit=USART_LastBit_Disable;

  USART_Init(USART1,&USART_InitStructure);

  USART_Cmd(USART1,ENABLE);

}
/*将C库中prinf函数重定向到USART*/
int fputc(int ch,FILE *f)
{
  USART_SendData(USART1,(u8)ch);

  while(USART_GetFlagStatus(USART1,USART_FLAG_TC)==RESET)
  {
  }
  return ch;