请教输入usart输入打印问题

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奔跑的猫ちゃん|

楼主 | 2018-7-3 18:48 | 只看该作者回帖奖励

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USART, index, tmp, ui, se

我写了个usart输入的数据打印函数，为什么打印回来的会是5位数的数字啊
uint8_t USART_Scanf(uint32_t value)
{
      uint32_t index = 0;
      uint32_t tmp[5] = {0, 0,0,0,0};
      while (index < 5)
      {
            while (USART_GetFlagStatus(USART1, USART_FLAG_RXNE) == RESET);
            tmp[index++] = (USART_ReceiveData(USART1));
            USART_SendData(USART3, tmp[index]);
            if ((tmp[index - 1] < 0x30) || (tmp[index - 1] > 0x39))
            {
            printf(&quot;
Please enter valid number between 0 and 9&quot;);
            index--;
            }
      }
      index = (tmp[4] - 0x30) + ((tmp[3] - 0x30) * 10+(tmp[2] - 0x30) *100+(tmp[1] - 0x30) *1000+(tmp[0] - 0x30)*10000);
      if (index > value)
      {
         printf(&quot;
Please enter valid number between 0 and %d&quot;, value);
         return 0xFF;
      }
      return index;
}

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