/* USART1 init function */
static void MX_USART1_UART_Init(void)
{

  huart1.Instance = USART1;
  huart1.Init.BaudRate = 19200;
  huart1.Init.WordLength = UART_WORDLENGTH_8B;
  huart1.Init.StopBits = UART_STOPBITS_1;
  huart1.Init.Parity = UART_PARITY_NONE;
  huart1.Init.Mode = UART_MODE_TX_RX;
  huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart1.Init.OverSampling = UART_OVERSAMPLING_16;
  huart1.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
  huart1.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_RXOVERRUNDISABLE_INIT|UART_ADVFEATURE_DMADISABLEONERROR_INIT;
  huart1.AdvancedInit.OverrunDisable = UART_ADVFEATURE_OVERRUN_DISABLE;
  huart1.AdvancedInit.DMADisableonRxError = UART_ADVFEATURE_DMA_DISABLEONRXERROR;
  if (HAL_UART_Init(&huart1) != HAL_OK)
  {
    _Error_Handler(__FILE__, __LINE__);
  }

}
使用CUBE配置的，无法实现数据发送，可以接收数据，查询if ((USART1->ISR & UART_FLAG_TC)== 0)数据一直不成立

是不是应该判断UART_FLAG_TC这位的逻辑判断的有问题，没有你的代码没法确定，正常逻辑应该等待是这位为1时（或者TXE为空时）发送数据。

你应该不断执行：
HAL_UART_Receive(&huart1, (uint8_t *)RX_BUF,1);

    /* While the UART in reception process, user can transmit data through
     "aTxBuffer" buffer */
  if(HAL_UART_Transmit_IT(&UartHandle, (uint8_t*)aTxMessage, 1)!= HAL_OK)
  {
        while(1) {};
  }
  /* Any data received will be stored "aRxBuffer" buffer : the number max of
     data received is 10 */
  if(HAL_UART_Receive_IT(&UartHandle, (uint8_t *)aRxBuffer, 1) != HAL_OK)
  {
        while(1) {};
  }

HAL_UART_Transmit直接就能发送了

问题解决了，是管脚没有重映射