/**
  * @brief Initializes the RS485 Driver enable feature according to the specified
  *         parameters in the UART_InitTypeDef and creates the associated handle .
  * @param huart: uart handle
  * @param UART_DEPolarity: select the driver enable polarity
  *        This parameter can be one of the following values:
  *          @arg UART_DE_POLARITY_HIGH: DE signal is active high
  *          @arg UART_DE_POLARITY_LOW: DE signal is active low
  * @param UART_DEAssertionTime: Driver Enable assertion time
  *                         5-bit value defining the time between the activation of the DE (Driver Enable)
  *                         signal and the beginning of the start bit. It is expressed in sample time
  *                         units (1/8 or 1/16 bit time, depending on the oversampling rate)         
  * @param UART_DEDeassertionTime: Driver Enable deassertion time          
  *                         5-bit value defining the time between the end of the last stop bit, in a
  *                         transmitted message, and the de-activation of the DE (Driver Enable) signal.
  *                         It is expressed in sample time units (1/8 or 1/16 bit time, depending on the
  *                         oversampling rate).        
  * @retval HAL status
  */
HAL_StatusTypeDef HAL_RS485Ex_Init(UART_HandleTypeDef *huart, uint32_t UART_DEPolarity, uint32_t UART_DEAssertionTime, uint32_t UART_DEDeassertionTime)
{
  uint32_t temp = 0x0;
  
  /* Check the UART handle allocation */
  if(huart == NULL)
  {
    return HAL_ERROR;
  }
  /* Check the Driver Enable UART instance */
  assert_param(IS_UART_DRIVER_ENABLE_INSTANCE(huart->Instance));
  
  /* Check the Driver Enable polarity */
  assert_param(IS_UART_DE_POLARITY(UART_DEPolarity));
  
  /* Check the Driver Enable assertion time */
  assert_param(IS_UART_ASSERTIONTIME(UART_DEAssertionTime));
  
  /* Check the Driver Enable deassertion time */
  assert_param(IS_UART_DEASSERTIONTIME(UART_DEDeassertionTime));
  
  if(huart->State == HAL_UART_STATE_RESET)
  {   
    /* Init the low level hardware : GPIO, CLOCK */
    HAL_UART_MspInit(huart);
  }
  
  huart->State = HAL_UART_STATE_BUSY;
  
  /* Disable the Peripheral */
  __HAL_UART_DISABLE(huart);
  
  /* Set the UART Communication parameters */
  if (UART_SetConfig(huart) == HAL_ERROR)
  {
    return HAL_ERROR;
  } 
  
  if (huart->AdvancedInit.AdvFeatureInit != UART_ADVFEATURE_NO_INIT)
  {
    UART_AdvFeatureConfig(huart);
  }
  
  /* Enable the Driver Enable mode by setting the DEM bit in the CR3 register */
  huart->Instance->CR3 |= USART_CR3_DEM;
  
  /* Set the Driver Enable polarity */
  MODIFY_REG(huart->Instance->CR3, USART_CR3_DEP, UART_DEPolarity);
  
  /* Set the Driver Enable assertion and deassertion times */
  temp = (UART_DEAssertionTime << UART_CR1_DEAT_ADDRESS_LSB_POS);
  temp |= (UART_DEDeassertionTime << UART_CR1_DEDT_ADDRESS_LSB_POS);
  MODIFY_REG(huart->Instance->CR1, (USART_CR1_DEDT|USART_CR1_DEAT), temp);
  
  /* Enable the Peripheral */
  __HAL_UART_ENABLE(huart);
  
  /* TEACK and/or REACK to check before moving huart->State to Ready */
  return (UART_CheckIdleState(huart));
}
Ejemplo n.º 2
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/**
  * @brief Initialize the RS485 Driver enable feature according to the specified
  *         parameters in the UART_InitTypeDef and creates the associated handle.
  * @param huart            UART handle.
  * @param Polarity         Select the driver enable polarity.
  *          This parameter can be one of the following values:
  *          @arg @ref UART_DE_POLARITY_HIGH DE signal is active high
  *          @arg @ref UART_DE_POLARITY_LOW  DE signal is active low
  * @param AssertionTime    Driver Enable assertion time:
  *       5-bit value defining the time between the activation of the DE (Driver Enable)
  *       signal and the beginning of the start bit. It is expressed in sample time
  *       units (1/8 or 1/16 bit time, depending on the oversampling rate)
  * @param DeassertionTime  Driver Enable deassertion time:
  *       5-bit value defining the time between the end of the last stop bit, in a
  *       transmitted message, and the de-activation of the DE (Driver Enable) signal.
  *       It is expressed in sample time units (1/8 or 1/16 bit time, depending on the
  *       oversampling rate).
  * @retval HAL status
  */
HAL_StatusTypeDef HAL_RS485Ex_Init(UART_HandleTypeDef *huart, uint32_t Polarity, uint32_t AssertionTime, uint32_t DeassertionTime)
{
  uint32_t temp;

  /* Check the UART handle allocation */
  if (huart == NULL)
  {
    return HAL_ERROR;
  }
  /* Check the Driver Enable UART instance */
  assert_param(IS_UART_DRIVER_ENABLE_INSTANCE(huart->Instance));

  /* Check the Driver Enable polarity */
  assert_param(IS_UART_DE_POLARITY(Polarity));

  /* Check the Driver Enable assertion time */
  assert_param(IS_UART_ASSERTIONTIME(AssertionTime));

  /* Check the Driver Enable deassertion time */
  assert_param(IS_UART_DEASSERTIONTIME(DeassertionTime));

  if (huart->gState == HAL_UART_STATE_RESET)
  {
    /* Allocate lock resource and initialize it */
    huart->Lock = HAL_UNLOCKED;

#if (USE_HAL_UART_REGISTER_CALLBACKS == 1)
    UART_InitCallbacksToDefault(huart);

    if (huart->MspInitCallback == NULL)
    {
      huart->MspInitCallback = HAL_UART_MspInit;
    }

    /* Init the low level hardware */
    huart->MspInitCallback(huart);
#else
    /* Init the low level hardware : GPIO, CLOCK, CORTEX */
    HAL_UART_MspInit(huart);
#endif /* (USE_HAL_UART_REGISTER_CALLBACKS) */
  }

  huart->gState = HAL_UART_STATE_BUSY;

  /* Disable the Peripheral */
  __HAL_UART_DISABLE(huart);

  /* Set the UART Communication parameters */
  if (UART_SetConfig(huart) == HAL_ERROR)
  {
    return HAL_ERROR;
  }

  if (huart->AdvancedInit.AdvFeatureInit != UART_ADVFEATURE_NO_INIT)
  {
    UART_AdvFeatureConfig(huart);
  }

  /* Enable the Driver Enable mode by setting the DEM bit in the CR3 register */
  SET_BIT(huart->Instance->CR3, USART_CR3_DEM);

  /* Set the Driver Enable polarity */
  MODIFY_REG(huart->Instance->CR3, USART_CR3_DEP, Polarity);

  /* Set the Driver Enable assertion and deassertion times */
  temp = (AssertionTime << UART_CR1_DEAT_ADDRESS_LSB_POS);
  temp |= (DeassertionTime << UART_CR1_DEDT_ADDRESS_LSB_POS);
  MODIFY_REG(huart->Instance->CR1, (USART_CR1_DEDT | USART_CR1_DEAT), temp);

  /* Enable the Peripheral */
  __HAL_UART_ENABLE(huart);

  /* TEACK and/or REACK to check before moving huart->gState and huart->RxState to Ready */
  return (UART_CheckIdleState(huart));
}