stm8l15x_i2c.c

STM8L的tim4定时器使用

  * @param  None
  * @retval The value of the PEC.
  */
uint8_t I2C_GetPEC(I2C_TypeDef* I2Cx)
{
  /* Return the PEC value */
  return (I2Cx->PECR);
}

/**
  * @}
  */

/** @defgroup I2C_Group4 DMA transfers management functions
 *  @brief   DMA transfers management functions
 *
@verbatim
 ===============================================================================
                         DMA transfers management functions
 ===============================================================================
  This section provides functions allowing to configure the I2C DMA channels
  requests.

@endverbatim
  * @{
  */

/**
  * @brief  Enables or disables the I2C DMA requests .
  * @param  I2Cx: where x can be 1 to select the specified I2C peripheral.
  * @param  NewState: Indicate the new I2C DMA state.
  *         This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void I2C_DMACmd(I2C_TypeDef* I2Cx, FunctionalState NewState)
{
  /* Check the parameters */
  assert_param(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)
  {
    /* Enable I2C DMA requests */
    I2Cx->ITR |= I2C_ITR_DMAEN;
  }
  else
  {
    /* Disable I2C DMA requests */
    I2Cx->ITR &= (uint8_t)(~I2C_ITR_DMAEN);
  }
}

/**
  * @brief  Specifies that the next DMA transfer is the last one .
  * @param  I2Cx: where x can be 1 to select the specified I2C peripheral.
  * @param  NewState: Indicate the new I2C DMA state.
  *         This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void I2C_DMALastTransferCmd(I2C_TypeDef* I2Cx, FunctionalState NewState)
{
  /* Check the parameters */
  assert_param(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)
  {
    /* Enable I2C DMA requests */
    I2Cx->ITR |= I2C_ITR_LAST;
  }
  else
  {
    /* Disable I2C DMA requests */
    I2Cx->ITR &= (uint8_t)(~I2C_ITR_LAST);
  }
}

/**
  * @}
  */

/** @defgroup I2C_Group5 Interrupts events and flags management functions
 *  @brief   Interrupts, events and flags management functions
 *
@verbatim
 ===============================================================================
                Interrupts, events 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.

 ===============================================================================
                          I2C State Monitoring Functions
 ===============================================================================
 This I2C driver provides three different ways for I2C state monitoring
  depending on the application requirements and constraints:


     1. Basic state monitoring (Using I2C_CheckEvent() function)
     -----------------------------------------------------------
    It compares the status registers (SR1, SR2 and SR3) content to a given event
    (can be the combination of one or more flags).
    It returns SUCCESS if the current status includes the given flags
    and returns ERROR if one or more flags are missing in the current status.
    - When to use:
      - This function is suitable for most applications as well as for startup
      activity since the events are fully described in the product reference manual
      (RM0031).
      - It is also suitable for users who need to define their own events.
    - Limitations:
      - If an error occurs (ie. error flags are set besides to the monitored flags),
        the I2C_CheckEvent() function may return SUCCESS despite the communication
        hold or corrupted real state.
        In this case, it is advised to use error interrupts to monitor the error
        events and handle them in the interrupt IRQ handler.

        @note
        For error management, it is advised to use the following functions:
          - I2C_ITConfig() to configure and enable the error interrupts (I2C_IT_ERR).
          - I2Cx_IRQHandler() which is called when the I2C interrupts occur.
            Where x is the peripheral instance (I2C1,...)
         - I2C_GetFlagStatus() or I2C_GetITStatus() to be called into the
           I2Cx_IRQHandler() function in order to determine which error occurred.
          - I2C_ClearFlag() or I2C_ClearITPendingBit() and/or I2C_SoftwareResetCmd()
            and/or I2C_GenerateStop() in order to clear the error flag and
            source and return to correct communication status.


     2. Advanced state monitoring (Using the function I2C_GetLastEvent())
     --------------------------------------------------------------------
     Using the function I2C_GetLastEvent() which returns the image of both SR1
     & SR3 status registers in a single word (uint16_t) (Status Register 3 value
     is shifted left by 8 bits and concatenated to Status Register 1).
     - When to use:
       - This function is suitable for the same applications above but it allows to
         overcome the limitations of I2C_GetFlagStatus() function (see below).
         The returned value could be compared to events already defined in the
         library (stm8l15x_i2c.h) or to custom values defined by user.
       - This function is suitable when multiple flags are monitored at the same time.
       - At the opposite of I2C_CheckEvent() function, this function allows user to
         choose when an event is accepted (when all events flags are set and no
         other flags are set or just when the needed flags are set like
         I2C_CheckEvent() function).
     - Limitations:
       - User may need to define his own events.
       - Same remark concerning the error management is applicable for this
         function if user decides to check only regular communication flags (and
         ignores error flags).


     3. Flag-based state monitoring (Using the function I2C_GetFlagStatus())
     -----------------------------------------------------------------------
     Using the function I2C_GetFlagStatus() which simply returns the status of
     one single flag (ie. I2C_FLAG_RXNE ...).
     - When to use:
        - This function could be used for specific applications or in debug phase.
        - It is suitable when only one flag checking is needed (most I2C events
          are monitored through multiple flags).
     - Limitations:
        - When calling this function, the Status register is accessed. Some flags are
          cleared when the status register is accessed. So checking the status
          of one Flag, may clear other ones.
        - Function may need to be called twice or more in order to monitor one
          single event.

  For detailed description of Events, please refer to section I2C_Events in
  stm8l15x_i2c.h file.


@endverbatim
  * @{
  */

/**
  * @brief  Enables or disables the specified I2C interrupt.
  * @param  I2Cx: where x can be 1 to select the specified I2C peripheral.
  * @param  I2C_IT: specifies the I2C interrupts sources to be enabled or disabled.
  *          This parameter can be any combination of the following values:
  *            @arg I2C_IT_BUF: Buffer interrupt mask
  *            @arg I2C_IT_EVT: Event interrupt mask
  *            @arg I2C_IT_ERR: Error interrupt mask
  * @param  NewState: State of the interrupt.
  *         This parameter can be: ENABLE or DISABLE.
  * @retval None
  */
void I2C_ITConfig(I2C_TypeDef* I2Cx, I2C_IT_TypeDef I2C_IT, FunctionalState NewState)
{
  /* Check functions parameters */
  assert_param(IS_I2C_CONFIG_IT(I2C_IT));
  assert_param(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)
  {
    /* Enable the selected I2C interrupts */
    I2Cx->ITR |= (uint8_t)I2C_IT;
  }
  else /* NewState == DISABLE */
  {
    /* Disable the selected I2C interrupts */
    I2Cx->ITR &= (uint8_t)(~(uint8_t)I2C_IT);
  }
}

/**
  * @brief  Reads the specified I2C register and returns its value.
  * @param  I2Cx: where x can be 1 to select the specified 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_FREQR: Frequency register.
  *            @arg I2C_Register_OARL: Own address register LSB.
  *            @arg I2C_Register_OARH: Own address register MSB
  *            @arg I2C_Register_DR: DR register.
  *            @arg I2C_Register_SR1: SR1 register.
  *            @arg I2C_Register_SR2: SR2 register.
  *            @arg I2C_Register_SR3: SR3 register.
  *            @arg I2C_Register_ITR: Interrupt and DMA register.
  *            @arg I2C_Register_CCRL: Clock control register low.
  *            @arg I2C_Register_CCRH: Clock control register high.
  *            @arg I2C_Register_TRISER: TRISE register.
  *            @arg I2C_Register_PECR: PEC register.
  * @retval The value of the read register.
  */

uint8_t I2C_ReadRegister(I2C_TypeDef* I2Cx, I2C_Register_TypeDef I2C_Register)
{
  __IO uint16_t tmp = 0;
  /* Check the parameters */
  assert_param(IS_I2C_REGISTER(I2C_Register));

  tmp = (uint16_t) I2Cx;
  tmp += I2C_Register;

  /* Return the selected register value */
  return (*(__IO uint8_t *) tmp);
}


/**
 ===============================================================================
                          1. Basic state monitoring
 ===============================================================================
 */

/**
  * @brief  Checks whether the last I2Cx Event is equal to the one passed
  *   as parameter.
  * @param  I2Cx: where x can be 1 to select the I2C peripheral.
  * @param  I2C_EVENT: specifies the event to be checked.
  *          This parameter can be one of the following values:
  *            @arg I2C_EVENT_SLAVE_TRANSMITTER_ADDRESS_MATCHED: EV1
  *            @arg I2C_EVENT_SLAVE_RECEIVER_ADDRESS_MATCHED: EV1
  *            @arg I2C_EVENT_SLAVE_GENERALCALLADDRESS_MATCHED: EV1
  *            @arg I2C_EVENT_SLAVE_BYTE_RECEIVED: EV2
  *            @arg (I2C_EVENT_SLAVE_BYTE_RECEIVED | I2C_FLAG_GENCALL): EV2
  *            @arg I2C_EVENT_SLAVE_BYTE_TRANSMITTED: EV3
  *            @arg (I2C_EVENT_SLAVE_BYTE_TRANSMITTED | I2C_FLAG_GENCALL): EV3
  *            @arg I2C_EVENT_SLAVE_ACK_FAILURE: EV3_2
  *            @arg I2C_EVENT_SLAVE_STOP_DETECTED: EV4
  *            @arg I2C_EVENT_MASTER_MODE_SELECT: EV5
  *            @arg I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED: EV6
  *            @arg I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED: EV6
  *            @arg I2C_EVENT_MASTER_BYTE_RECEIVED: EV7
  *            @arg I2C_EVENT_MASTER_BYTE_TRANSMITTING: EV8
  *            @arg I2C_EVENT_MASTER_BYTE_TRANSMITTED: EV8_2
  *            @arg I2C_EVENT_MASTER_MODE_ADDRESS10: EV9
  *
  * @note: For detailed description of Events, please refer to section
  *    I2C_Events in stm8l15x_i2c.h file.
  *
  * @retval An ErrorStatus enumeration value:
  *         - SUCCESS: Last event is equal to the I2C_EVENT
  *         - ERROR: Last event is different from the I2C_EVENT
  */
ErrorStatus I2C_CheckEvent(I2C_TypeDef* I2Cx, I2C_Event_TypeDef I2C_Event)
{
  __IO uint16_t lastevent = 0x00;
  uint8_t flag1 = 0x00 ;
  uint8_t flag2 = 0x00;
  ErrorStatus status = ERROR;

  /* Check the parameters */
  assert_param(IS_I2C_EVENT(I2C_Event));

  if (I2C_Event == I2C_EVENT_SLAVE_ACK_FAILURE)
  {
    lastevent = I2Cx->SR2 & I2C_SR2_AF;
  }
  else
  {
    flag1 = I2Cx->SR1;
    flag2 = I2Cx->SR3;
    lastevent = ((uint16_t)((uint16_t)flag2 << (uint16_t)8) | (uint16_t)flag1);
  }
  /* Check whether the last event is equal to I2C_EVENT */
  if (((uint16_t)lastevent & (uint16_t)I2C_Event) == (uint16_t)I2C_Event)
  {
    /* SUCCESS: last event is equal to I2C_EVENT */
    status = SUCCESS;
  }
  else
  {
    /* ERROR: last event is different from I2C_EVENT */
    status = ERROR;
  }

  /* Return status */
  return status;
}

/**
 ===============================================================================
                          2. Advanced state monitoring
 ===============================================================================
 */

/**
  * @brief  Returns the last I2C Event.
  * @param  I2Cx: where x can be 1 to select the specified I2C peripheral.
  *
  * @note: For detailed description of Events, please refer to section
  *    I2C_Events in stm8l15xx_i2c.h file.
  *
  * @retval The last event
  */
I2C_Event_TypeDef I2C_GetLastEvent(I2C_TypeDef* I2Cx)
{
  __IO uint16_t lastevent = 0;
  uint16_t flag1 = 0;
  uint16_t flag2 = 0;

  if ((I2Cx->SR2 & I2C_SR2_AF) != 0x00)
  {
    lastevent = I2C_EVENT_SLAVE_ACK_FAILURE;
  }
  else
  {
    /* Read the I2C status register */
    flag1 = I2Cx->SR1;
    flag2 = I2Cx->SR3;

    /* Get the last event value from I2C status register */
    lastevent = ((uint16_t)((uint16_t)flag2 << 8) | (uint16_t)flag1);
  }
  /* Return status */
  return (I2C_Event_TypeDef)lastevent;
}

/**
 ===============================================================================
                          3. Flag-based state monitoring
 ===============================================================================
 */

/**
  * @brief  Checks whether the specified I2C flag is set or not.
  * @param  I2Cx: where x can be 1 select the I2C peripheral.
  * @param  I2C_FLAG: specifies the flag to check.
  *          This parameter can be one of the following values:
  *            @arg I2C_FLAG_SMBHOST: SMBus host header (Slave mode)
  *            @arg I2C_FLAG_SMBDEFAULT: SMBus default header (Slave mode)
  *            @arg I2C_FLAG_GENCALL: General call header flag (Slave mode)
  *            @arg I2C_FLAG_TRA: Transmitter/Receiver flag
  *            @arg I2C_FLAG_BUSY: Bus busy flag
  *            @arg I2C_FLAG_MSL: Master/Slave flag
  *            @arg I2C_FLAG_SMBALERT: SMBus Alert flag
  *            @arg I2C_FLAG_TIMEOUT: Timeout or Tlow error flag
  *            @arg I2C_FLAG_PECERR: PEC error in reception flag
  *            @arg I2C_FLAG_OVR: Overrun/Underrun flag (Slave mode)
  *            @arg I2C_FLAG_AF: Acknowledge failure flag
  *            @arg I2C_FLAG_ARLO: Arbitration lost flag (Master mode)
  *            @arg I2C_FLAG_BERR: Bus error flag
  *            @arg I2C_FLAG_TXE: Data register empty flag (Transmitter)
  *            @arg I2C_FLAG_RXNE: Data register not empty (Receiver) flag
  *            @arg I2C_FLAG_STOPF: Stop detection flag (Slave mode)
  *            @arg I2C_FLAG_ADD10: 10-bit header sent flag (Master mode)
  *            @arg I2C_FLAG_BTF: Byte transfer finished flag
  *            @arg I2C_FLAG_ADDR: Address sent flag (Master mode) 揂DSL