使用串口4的奇校验收发数据，配置如下：
  USART_InitStructure.USART_BaudRate = 115200;
  USART_InitStructure.USART_WordLength = USART_WordLength_9b;
  USART_InitStructure.USART_StopBits = USART_StopBits_1;
  USART_InitStructure.USART_Parity =  USART_Parity_Odd;
  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
  USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
  USART_Init(UART4, &USART_InitStructure);


用PC机串口助手通讯，PC机可以收到stm32发送的数据，但是PC机发送的数据stm32不能收到！！！
问题出在哪里？？