串口无法输出无符号char郁闷

pkjapan · 发表于 2018-12-23 22:46:50

本帖最后由 pkjapan 于 2018-12-23 22:48 编辑

串口输出超过128就会变成0x3f，比如打印一个累计的unsigned char变量，到了0x7f  往后就变成0x3f了郁闷啊按理应该是 0x80 啊
这两种都没法输出unsigned char
拿到串口打不出0x7f以上的数？
void USART_Transmit(USART_TypeDef *USARTx,uint16_t ch_data)
{
      // Loop until the end of transmission
      while (USART_GetFlagStatus(USARTx, USART_FLAG_TC) == RESET)
      {
            ;
      }
      USART_SendData(USARTx, (uint16_t)ch_data);
}

void USART4_Transmit(char ch_data)
{
      // Loop until the end of transmission

      while (USART_GetFlagStatus(UART4, USART_FLAG_TC) == RESET)
      {
            ;
            }
      USART_SendData(UART4, (char)ch_data);
}

void Usart4_Init(unsigned int baud)
{

      GPIO_InitTypeDef gpioInitStruct;
      USART_InitTypeDef usartInitStruct;
      NVIC_InitTypeDef nvicInitStruct;

      RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
      RCC_APB1PeriphClockCmd(RCC_APB1Periph_UART4, ENABLE);

      //PC10       TXD
      gpioInitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
      gpioInitStruct.GPIO_Pin = GPIO_Pin_10;
      gpioInitStruct.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOC, &gpioInitStruct);

      //PC11       RXD
      gpioInitStruct.GPIO_Mode = GPIO_Mode_IN_FLOATING;
      gpioInitStruct.GPIO_Pin = GPIO_Pin_11;
      gpioInitStruct.GPIO_Speed = GPIO_Speed_50MHz;
      GPIO_Init(GPIOC, &gpioInitStruct);

      usartInitStruct.USART_BaudRate = baud;
      usartInitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;             //无硬件流控
      usartInitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;                                              //接收和发送
      usartInitStruct.USART_Parity = USART_Parity_No;                                                                      //无校验
      usartInitStruct.USART_StopBits = USART_StopBits_1;                                                             //1位停止位
      usartInitStruct.USART_WordLength = USART_WordLength_8b;                                                       //8位数据位
      USART_Init(UART4, &usartInitStruct);

      USART_Cmd(UART4, ENABLE);                                                                                                             //使能串口

      USART_ITConfig(UART4, USART_IT_RXNE, ENABLE);                                                                      //使能接收中断

      nvicInitStruct.NVIC_IRQChannel = UART4_IRQn;
      nvicInitStruct.NVIC_IRQChannelCmd = ENABLE;
      nvicInitStruct.NVIC_IRQChannelPreemptionPriority = 0;
      nvicInitStruct.NVIC_IRQChannelSubPriority = 0;
      NVIC_Init(&nvicInitStruct);

}

void USART_SendData(USART_TypeDef* USARTx, uint16_t Data)
{
  /* Check the parameters */
  assert_param(IS_USART_ALL_PERIPH(USARTx));
  assert_param(IS_USART_DATA(Data));

  /* Transmit Data */
  USARTx->DR = (Data & (uint16_t)0x01FF);
}

疯了啊？？？？？？？