stm32f0xx_i2c.c

stm32f0固件库

         I2C registers.

@endverbatim
  * @{
  */

  /**
  * @brief  Reads the specified I2C register and returns its value.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_Register: specifies the register to read.
  *   This parameter can be one of the following values:
  *     @arg I2C_Register_CR1: CR1 register.
  *     @arg I2C_Register_CR2: CR2 register.
  *     @arg I2C_Register_OAR1: OAR1 register.
  *     @arg I2C_Register_OAR2: OAR2 register.
  *     @arg I2C_Register_TIMINGR: TIMING register.
  *     @arg I2C_Register_TIMEOUTR: TIMEOUTR register.
  *     @arg I2C_Register_ISR: ISR register.
  *     @arg I2C_Register_ICR: ICR register.
  *     @arg I2C_Register_PECR: PECR register.
  *     @arg I2C_Register_RXDR: RXDR register.
  *     @arg I2C_Register_TXDR: TXDR register.
  * @retval The value of the read register.
  */
uint32_t I2C_ReadRegister(I2C_TypeDef* I2Cx, uint8_t I2C_Register)
{
  __IO uint32_t tmp = 0;

  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_I2C_REGISTER(I2C_Register));

  tmp = (uint32_t)I2Cx;
  tmp += I2C_Register;

  /* Return the selected register value */
  return (*(__IO uint32_t *) tmp);
}

/**
  * @}
  */  
  
/** @defgroup I2C_Group5 Data transfers management functions
 *  @brief   Data transfers management functions 
 *
@verbatim
 ===============================================================================
                ##### Data transfers management functions #####
 ===============================================================================  
    [..] This subsection provides a set of functions allowing to manage 
         the I2C data transfers.

    [..] The read access of the I2C_RXDR register can be done using 
         the I2C_ReceiveData() function and returns the received value.
         Whereas a write access to the I2C_TXDR can be done using I2C_SendData()
         function and stores the written data into TXDR.
@endverbatim
  * @{
  */  
  
/**
  * @brief  Sends a data byte through the I2Cx peripheral.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  Data: Byte to be transmitted..
  * @retval None
  */
void I2C_SendData(I2C_TypeDef* I2Cx, uint8_t Data)
{
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  
  /* Write in the DR register the data to be sent */
  I2Cx->TXDR = (uint8_t)Data;
}

/**
  * @brief  Returns the most recent received data by the I2Cx peripheral.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @retval The value of the received data.
  */
uint8_t I2C_ReceiveData(I2C_TypeDef* I2Cx)
{
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  
  /* Return the data in the DR register */
  return (uint8_t)I2Cx->RXDR;
}  

/**
  * @}
  */ 


/** @defgroup I2C_Group6 DMA transfers management functions
 *  @brief   DMA transfers management functions 
 *
@verbatim
 ===============================================================================
                ##### DMA transfers management functions #####
 ===============================================================================  
    [..] This section provides two functions that can be used only in DMA mode.
    [..] In DMA Mode, the I2C communication can be managed by 2 DMA Channel 
         requests:
         (#) I2C_DMAReq_Tx: specifies the Tx buffer DMA transfer request.
         (#) I2C_DMAReq_Rx: specifies the Rx buffer DMA transfer request.
    [..] In this Mode it is advised to use the following function:
         (+) I2C_DMACmd(I2C_TypeDef* I2Cx, uint32_t I2C_DMAReq, FunctionalState NewState);
@endverbatim
  * @{
  */  
    
/**
  * @brief  Enables or disables the I2C DMA interface.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_DMAReq: specifies the I2C DMA transfer request to be enabled or disabled. 
  *   This parameter can be any combination of the following values:
  *     @arg I2C_DMAReq_Tx: Tx DMA transfer request
  *     @arg I2C_DMAReq_Rx: Rx DMA transfer request
  * @param  NewState: new state of the selected I2C DMA transfer request.
  *         This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void I2C_DMACmd(I2C_TypeDef* I2Cx, uint32_t I2C_DMAReq, FunctionalState NewState)
{
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_FUNCTIONAL_STATE(NewState));
  assert_param(IS_I2C_DMA_REQ(I2C_DMAReq));

  if (NewState != DISABLE)
  {
    /* Enable the selected I2C DMA requests */
    I2Cx->CR1 |= I2C_DMAReq;
  }
  else
  {
    /* Disable the selected I2C DMA requests */
    I2Cx->CR1 &= (uint32_t)~I2C_DMAReq;
  }
}
/**
  * @}
  */  


/** @defgroup I2C_Group7 Interrupts and flags management functions
 *  @brief   Interrupts and flags management functions 
 *
@verbatim
 ===============================================================================
             ##### Interrupts and flags management functions  #####
 ===============================================================================  
    [..] This section provides functions allowing to configure the I2C Interrupts 
         sources and check or clear the flags or pending bits status.
         The user should identify which mode will be used in his application to manage 
         the communication: Polling mode, Interrupt mode or DMA mode(refer I2C_Group6).

  *** Polling Mode ***
  ====================
    [..] In Polling Mode, the I2C communication can be managed by 15 flags:
        (#) I2C_FLAG_TXE: to indicate the status of Transmit data register empty flag.
        (#) I2C_FLAG_TXIS: to indicate the status of Transmit interrupt status flag .
        (#) I2C_FLAG_RXNE: to indicate the status of Receive data register not empty flag.
        (#) I2C_FLAG_ADDR: to indicate the status of Address matched flag (slave mode).
        (#) I2C_FLAG_NACKF: to indicate the status of NACK received flag.
        (#) I2C_FLAG_STOPF: to indicate the status of STOP detection flag.
        (#) I2C_FLAG_TC: to indicate the status of Transfer complete flag(master mode).
        (#) I2C_FLAG_TCR: to indicate the status of Transfer complete reload flag.
        (#) I2C_FLAG_BERR: to indicate the status of Bus error flag.
        (#) I2C_FLAG_ARLO: to indicate the status of Arbitration lost flag.
        (#) I2C_FLAG_OVR: to indicate the status of Overrun/Underrun flag.
        (#) I2C_FLAG_PECERR: to indicate the status of PEC error in reception flag.
        (#) I2C_FLAG_TIMEOUT: to indicate the status of Timeout or Tlow detection flag.
        (#) I2C_FLAG_ALERT: to indicate the status of SMBus Alert flag.
        (#) I2C_FLAG_BUSY: to indicate the status of Bus busy flag.

    [..] In this Mode it is advised to use the following functions:
        (+) FlagStatus I2C_GetFlagStatus(I2C_TypeDef* I2Cx, uint32_t I2C_FLAG);
        (+) void I2C_ClearFlag(I2C_TypeDef* I2Cx, uint32_t I2C_FLAG);

    [..]
        (@)Do not use the BUSY flag to handle each data transmission or reception.It is 
           better to use the TXIS and RXNE flags instead.

  *** Interrupt Mode ***
  ======================
    [..] In Interrupt Mode, the I2C communication can be managed by 7 interrupt sources
         and 15 pending bits: 
    [..] Interrupt Source:
        (#) I2C_IT_ERRI: specifies the interrupt source for the Error interrupt.
        (#) I2C_IT_TCI: specifies the interrupt source for the Transfer Complete interrupt.
        (#) I2C_IT_STOPI: specifies the interrupt source for the Stop Detection interrupt.
        (#) I2C_IT_NACKI: specifies the interrupt source for the Not Acknowledge received interrupt.
        (#) I2C_IT_ADDRI: specifies the interrupt source for the Address Match interrupt.
        (#) I2C_IT_RXI: specifies the interrupt source for the RX interrupt.
        (#) I2C_IT_TXI: specifies the interrupt source for the TX interrupt.

    [..] Pending Bits:
        (#) I2C_IT_TXIS: to indicate the status of Transmit interrupt status flag.
        (#) I2C_IT_RXNE: to indicate the status of Receive data register not empty flag.
        (#) I2C_IT_ADDR: to indicate the status of Address matched flag (slave mode).
        (#) I2C_IT_NACKF: to indicate the status of NACK received flag.
        (#) I2C_IT_STOPF: to indicate the status of STOP detection flag.
        (#) I2C_IT_TC: to indicate the status of Transfer complete flag (master mode).
        (#) I2C_IT_TCR: to indicate the status of Transfer complete reload flag.
        (#) I2C_IT_BERR: to indicate the status of Bus error flag.
        (#) I2C_IT_ARLO: to indicate the status of Arbitration lost flag.
        (#) I2C_IT_OVR: to indicate the status of Overrun/Underrun flag.
        (#) I2C_IT_PECERR: to indicate the status of PEC error in reception flag.
        (#) I2C_IT_TIMEOUT: to indicate the status of Timeout or Tlow detection flag.
        (#) I2C_IT_ALERT: to indicate the status of SMBus Alert flag.

    [..] In this Mode it is advised to use the following functions:
        (+) void I2C_ClearITPendingBit(I2C_TypeDef* I2Cx, uint32_t I2C_IT);
        (+) ITStatus I2C_GetITStatus(I2C_TypeDef* I2Cx, uint32_t I2C_IT);

@endverbatim
  * @{
  */  

/**
  * @brief  Checks whether the specified I2C flag is set or not.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_FLAG: specifies the flag to check. 
  *   This parameter can be one of the following values:
  *     @arg I2C_FLAG_TXE: Transmit data register empty
  *     @arg I2C_FLAG_TXIS: Transmit interrupt status
  *     @arg I2C_FLAG_RXNE: Receive data register not empty
  *     @arg I2C_FLAG_ADDR: Address matched (slave mode)
  *     @arg I2C_FLAG_NACKF: NACK received flag
  *     @arg I2C_FLAG_STOPF: STOP detection flag
  *     @arg I2C_FLAG_TC: Transfer complete (master mode)
  *     @arg I2C_FLAG_TCR: Transfer complete reload
  *     @arg I2C_FLAG_BERR: Bus error
  *     @arg I2C_FLAG_ARLO: Arbitration lost
  *     @arg I2C_FLAG_OVR: Overrun/Underrun
  *     @arg I2C_FLAG_PECERR: PEC error in reception
  *     @arg I2C_FLAG_TIMEOUT: Timeout or Tlow detection flag
  *     @arg I2C_FLAG_ALERT: SMBus Alert
  *     @arg I2C_FLAG_BUSY: Bus busy
  * @retval The new state of I2C_FLAG (SET or RESET).
  */
FlagStatus I2C_GetFlagStatus(I2C_TypeDef* I2Cx, uint32_t I2C_FLAG)
{
  uint32_t tmpreg = 0;
  FlagStatus bitstatus = RESET;
  
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_I2C_GET_FLAG(I2C_FLAG));
  
  /* Get the ISR register value */
  tmpreg = I2Cx->ISR;
  
  /* Get flag status */
  tmpreg &= I2C_FLAG;
  
  if(tmpreg != 0)
  {
    /* I2C_FLAG is set */
    bitstatus = SET;
  }
  else
  {
    /* I2C_FLAG is reset */
    bitstatus = RESET;
  }
  return bitstatus;
} 

/**
  * @brief  Clears the I2Cx's pending flags.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_FLAG: specifies the flag to clear. 
  *   This parameter can be any combination of the following values:
  *     @arg I2C_FLAG_ADDR: Address matched (slave mode)
  *     @arg I2C_FLAG_NACKF: NACK received flag
  *     @arg I2C_FLAG_STOPF: STOP detection flag
  *     @arg I2C_FLAG_BERR: Bus error
  *     @arg I2C_FLAG_ARLO: Arbitration lost
  *     @arg I2C_FLAG_OVR: Overrun/Underrun
  *     @arg I2C_FLAG_PECERR: PEC error in reception
  *     @arg I2C_FLAG_TIMEOUT: Timeout or Tlow detection flag
  *     @arg I2C_FLAG_ALERT: SMBus Alert
  * @retval The new state of I2C_FLAG (SET or RESET).
  */
void I2C_ClearFlag(I2C_TypeDef* I2Cx, uint32_t I2C_FLAG)
{ 
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_I2C_CLEAR_FLAG(I2C_FLAG));

  /* Clear the selected flag */
  I2Cx->ICR = I2C_FLAG;
  }

/**
  * @brief  Checks whether the specified I2C interrupt has occurred or not.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_IT: specifies the interrupt source to check.
  *   This parameter can be one of the following values:
  *     @arg I2C_IT_TXIS: Transmit interrupt status
  *     @arg I2C_IT_RXNE: Receive data register not empty
  *     @arg I2C_IT_ADDR: Address matched (slave mode)
  *     @arg I2C_IT_NACKF: NACK received flag
  *     @arg I2C_IT_STOPF: STOP detection flag
  *     @arg I2C_IT_TC: Transfer complete (master mode)
  *     @arg I2C_IT_TCR: Transfer complete reload
  *     @arg I2C_IT_BERR: Bus error
  *     @arg I2C_IT_ARLO: Arbitration lost
  *     @arg I2C_IT_OVR: Overrun/Underrun
  *     @arg I2C_IT_PECERR: PEC error in reception
  *     @arg I2C_IT_TIMEOUT: Timeout or Tlow detection flag
  *     @arg I2C_IT_ALERT: SMBus Alert
  * @retval The new state of I2C_IT (SET or RESET).
  */
ITStatus I2C_GetITStatus(I2C_TypeDef* I2Cx, uint32_t I2C_IT)
{
  uint32_t tmpreg = 0;
  ITStatus bitstatus = RESET;
  
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_I2C_GET_IT(I2C_IT));
  
  /* Get the ISR register value */
  tmpreg = I2Cx->ISR;
  
  /* Get flag status */
  tmpreg &= I2C_IT;
  
  if(tmpreg != 0)
  {
    /* I2C_IT is set */
    bitstatus = SET;
  }
  else
  {
    /* I2C_IT is reset */
    bitstatus = RESET;
  }
  return bitstatus;
} 

/**
  * @brief  Clears the I2Cx's interrupt pending bits.
  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
  * @param  I2C_IT: specifies the interrupt pending bit to clear.
  *   This parameter can be any combination of the following values:
  *     @arg I2C_IT_ADDR: Address matched (slave mode)
  *     @arg I2C_IT_NACKF: NACK received flag
  *     @arg I2C_IT_STOPF: STOP detection flag
  *     @arg I2C_IT_BERR: Bus error
  *     @arg I2C_IT_ARLO: Arbitration lost
  *     @arg I2C_IT_OVR: Overrun/Underrun
  *     @arg I2C_IT_PECERR: PEC error in reception
  *     @arg I2C_IT_TIMEOUT: Timeout or Tlow detection flag
  *     @arg I2C_IT_ALERT: SMBus Alert
  * @retval The new state of I2C_IT (SET or RESET).
  */
void I2C_ClearITPendingBit(I2C_TypeDef* I2Cx, uint32_t I2C_IT)
{
  /* Check the parameters */
  assert_param(IS_I2C_ALL_PERIPH(I2Cx));
  assert_param(IS_I2C_CLEAR_IT(I2C_IT));

  /* Clear the selected flag */
  I2Cx->ICR = I2C_IT;
}

/**
  * @}
  */  
  
/**
  * @}
  */

/**
  * @}
  */

/**
  * @}
  */

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