stm8s_spi.c

STM8全部资料

* SPI_CalculateCRCCmd(ENABLE);
* @endcode
*/
void SPI_CalculateCRCCmd(FunctionalState NewState)
{
  /* Check function parameters */
  assert_param(IS_FUNCTIONALSTATE_OK(NewState));

  /* SPI must be disable forcorrect operation od Hardware CRC calculation */
  SPI_Cmd(DISABLE);

  if (NewState != DISABLE)
  {
    SPI->CR2 |= SPI_CR2_CRCEN; /* Enable the CRC calculation*/
  }
  else
  {
    SPI->CR2 &= (u8)(~SPI_CR2_CRCEN); /* Disable the CRC calculation*/
  }
}

/**
* @brief Returns the transmit or the receive CRC register value.
* @param[in] SPI_CRC Specifies the CRC register to be read.
* @retval u8 The selected CRC register value.
* @par Required preconditions:
* None
* @par Called functions:
* None
* @par Example:
* @code
* SPI_GetCRC(SPI_CRC_TX);
* @endcode
*/
u8 SPI_GetCRC(SPI_CRC_TypeDef SPI_CRC)
{
  u8 crcreg = 0;

  /* Check function parameters */
  assert_param(IS_SPI_CRC_OK(SPI_CRC));

  if (SPI_CRC != SPI_CRC_RX)
  {
    crcreg = SPI->TXCRCR;  /* Get the Tx CRC register*/
  }
  else
  {
    crcreg = SPI->RXCRCR; /* Get the Rx CRC register*/
  }

  /* Return the selected CRC register status*/
  return crcreg;
}

/**
* @brief Reset the Rx CRCR and Tx CRCR registers.
* @par Parameters:
* None
* @retval void None
* @par Required preconditions:
* None
* @par Called functions: SPI_CalculateCRCCmd and SPI_Cmd.
* @par Example:
* @code
* SPI_ResetCRC();
* @endcode
*/
void SPI_ResetCRC(void)
{
  /* Rx CRCR & Tx CRCR registers are reset when CRCEN (hardware calculation)
     bit in SPI_CR2 is written to 1 (enable) */
  SPI_CalculateCRCCmd(ENABLE);

  /* Previous function disable the SPI */
  SPI_Cmd(ENABLE);
}

/**
* @brief Returns the CRC Polynomial register value.
* @par Parameters:
* None
* @retval u8 The CRC Polynomial register value.
* @par Required preconditions:
* None
* @par Called functions:
* None
* @par Example:
* @code
* u8 polynomial;
* polynomial = SPI_GetCRCPolynomial();
* @endcode
*/
u8 SPI_GetCRCPolynomial(void)
{
  return SPI->CRCPR; /* Return the CRC polynomial register */
}

/**
* @brief Selects the data transfer direction in bi-directional mode.
* @param[in] SPI_Direction Specifies the data transfer direction in bi-directional mode.
* @retval void None
* @par Required preconditions:
* None
* @par Called functions:
* None
* @par Example:
* @code
* SPI_BiDirectionalLineConfig(SPI_DIRECTION_TX);
* @endcode
*/
void SPI_BiDirectionalLineConfig(SPI_Direction_TypeDef SPI_Direction)
{
  /* Check function parameters */
  assert_param(IS_SPI_DIRECTION_OK(SPI_Direction));

  if (SPI_Direction != SPI_DIRECTION_RX)
  {
    SPI->CR2 |= SPI_CR2_BDOE; /* Set the Tx only mode*/
  }
  else
  {
    SPI->CR2 &= (u8)(~SPI_CR2_BDOE); /* Set the Rx only mode*/
  }
}

/**
  * @brief Checks whether the specified SPI flag is set or not.
  * @param[in] SPI_FLAG : Specifies the flag to check.
  * This parameter can be any of the @ref SPI_Flag_TypeDef enumeration.
  * @retval FlagStatus : Indicates the state of SPI_FLAG.
  * This parameter can be any of the @ref FlagStatus enumeration.
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Example:
 * This example shows how to call the function:
  * @code
  * FlagStatus SPI_Flag;
  * SPI_Flag = SPI_GetFlagStatus(SPI_FLAG_TXE);
  * @endcode
  */

FlagStatus SPI_GetFlagStatus(SPI_Flag_TypeDef SPI_FLAG)
{
  FlagStatus status = RESET;
  /* Check parameters */
  assert_param(IS_SPI_FLAGS_OK(SPI_FLAG));

  /* Check the status of the specified SPI flag */
  if ((SPI->SR & (u8)SPI_FLAG) != (u8)RESET)
  {
    status = SET; /* SPI_FLAG is set */
  }
  else
  {
    status = RESET; /* SPI_FLAG is reset*/
  }

  /* Return the SPI_FLAG status */
  return status;
}

/**
  * @brief Clears the SPI flags.
  * @param[in] SPI_FLAG : Specifies the flag to clear.
  * This parameter can be one of the following values:
  * - SPI_FLAG_CRCERR
  * - SPI_FLAG_WKUP
  * @par Notes
  * - OVR (OverRun Error) interrupt pending bit is cleared by software sequence:
  *   a read operation to SPI_DR register (SPI_ReceiveData()) followed by
  *   a read operation to SPI_SR register (SPI_GetFlagStatus()).
  * - MODF (Mode Fault) interrupt pending bit is cleared by software sequence:
  *   a read/write operation to SPI_SR register (SPI_GetFlagStatus()) followed by
  *   a write operation to SPI_CR1 register (SPI_Cmd() to enable the SPI).
  * @retval void : None
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Example:
  * This example shows how to call the function:
  * @code
  * SPI_ClearFlag(SPI_FLAG_OVR);
  * @endcode
  */
void SPI_ClearFlag(SPI_Flag_TypeDef SPI_FLAG)
{
  assert_param(IS_SPI_CLEAR_FLAGS_OK(SPI_FLAG));
  /* Clear the flag bit */
  SPI->SR = (u8)(~SPI_FLAG);
}

/**
  * @brief Checks whether the specified interrupt has occurred or not.
  * @param[in] SPI_IT: Specifies the SPI interrupt pending bit to check.
  * This parameter can be one of the following values:
 * - SPI_IT_CRCERR
  * - SPI_IT_WKUP
 * - SPI_IT_OVR
  * - SPI_IT_MODF
 * - SPI_IT_RXNE
 * - SPI_IT_TXE
 * @retval ITStatus : Indicates the state of the SPI_IT.
  * This parameter can be any of the @ref ITStatus enumeration.
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Example:
 * This example shows how to call the function:
  * @code
  * ITStatus SPI_Interrupt;
  * SPI_Interrupt = SPI_GetITStatus(SPI_IT_OVR);
  * @endcode
  */
ITStatus SPI_GetITStatus(SPI_IT_TypeDef SPI_IT)
{
  ITStatus pendingbitstatus = RESET;
  u8 itpos = 0;
  u8 itmask1 = 0;
  u8 itmask2 = 0;
  u8 enablestatus = 0;
  assert_param(IS_SPI_GET_IT_OK(SPI_IT));
  /* Get the SPI IT index */
  itpos = (u8)((u8)1 << ((u8)SPI_IT & (u8)0x0F));

  /* Get the SPI IT mask */
  itmask1 = (u8)((u8)SPI_IT >> (u8)4);
  /* Set the IT mask */
  itmask2 = (u8)((u8)1 << itmask1);
  /* Get the SPI_ITPENDINGBIT enable bit status */
  enablestatus = (u8)((u8)SPI->ICR & itmask2);
  /* Check the status of the specified SPI interrupt */
  if (((SPI->SR & itpos) != RESET) && enablestatus)
  {
    /* SPI_ITPENDINGBIT is set */
    pendingbitstatus = SET;
  }
  else
  {
    /* SPI_ITPENDINGBIT is reset */
    pendingbitstatus = RESET;
  }
  /* Return the SPI_ITPENDINGBIT status */
  return  pendingbitstatus;
}
/**
  * @brief Clears the interrupt pending bits.
  * @param[in] SPI_IT: Specifies the interrupt pending bit to clear.
  * This parameter can be one of the following values:
  * - SPI_IT_CRCERR
  * - SPI_IT_WKUP
  * @par Notes
  *    - OVR (OverRun Error) interrupt pending bit is cleared by software sequence:
  *      a read operation to SPI_DR register (SPI_ReceiveData()) followed by
  *      a read operation to SPI_SR register (SPI_GetITStatus()).
  *    - MODF (Mode Fault) interrupt pending bit is cleared by software sequence:
  *      a read/write operation to SPI_SR register (SPI_GetITStatus()) followed by
  *      a write operation to SPI_CR1 register (SPI_Cmd() to enable the SPI).
  * @retval void : None
  * @par Required preconditions:
  * None
  * @par Called functions:
  * None
  * @par Example:
  * This example shows how to call the function:
  * @code
  * SPI_ClearITPendingBit(SPI_IT_WKUP);
  * @endcode
  */
void SPI_ClearITPendingBit(SPI_IT_TypeDef SPI_IT)
{
  u8 itpos = 0;
  assert_param(IS_SPI_CLEAR_IT_OK(SPI_IT));

  /* Clear  SPI_IT_CRCERR or SPI_IT_WKUP interrupt pending bits */

  /* Get the SPI pending bit index */
  itpos = (u8)((u8)1 << (((u8)SPI_IT & (u8)0xF0) >> 4));
  /* Clear the pending bit */
  SPI->SR = (u8)(~itpos);

}
/**
  * @}
  */

/******************* (C) COPYRIGHT 2008 STMicroelectronics *****END OF FILE****/