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/**
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 * @brief
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 ****************************************************************************************
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 *
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 *                         I2C State Monitoring Functions
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 *
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 ****************************************************************************************
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 * This I2C driver provides three different ways for I2C state monitoring
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 *  depending on the application requirements and constraints:
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 *
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 *
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 * 1) Basic state monitoring:
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 *    Using I2C_CheckEvent() function:
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 *    It compares the status registers (SR1 and SR2) content to a given event
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 *    (can be the combination of one or more flags).
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 *    It returns SUCCESS if the current status includes the given flags
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 *    and returns ERROR if one or more flags are missing in the current status.
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 *    - When to use:
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 *      - This function is suitable for most applications as well as for startup
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 *      activity since the events are fully described in the product reference manual
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 *      (RM0008).
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 *      - It is also suitable for users who need to define their own events.
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 *    - Limitations:
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 *      - If an error occurs (ie. error flags are set besides to the monitored flags),
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 *        the I2C_CheckEvent() function may return SUCCESS despite the communication
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 *        hold or corrupted real state.
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 *        In this case, it is advised to use error interrupts to monitor the error
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 *        events and handle them in the interrupt IRQ handler.
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 *
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 *        @note
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 *        For error management, it is advised to use the following functions:
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 *          - I2C_ITConfig() to configure and enable the error interrupts (I2C_IT_ERR).
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 *          - I2Cx_ER_IRQHandler() which is called when the error interrupt occurs.
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 *            Where x is the peripheral instance (I2C1, I2C2 ...)
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 *          - I2C_GetFlagStatus() or I2C_GetITStatus() to be called into I2Cx_ER_IRQHandler()
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 *            in order to determine which error occurred.
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 *          - I2C_ClearFlag() or I2C_ClearITPendingBit() and/or I2C_SoftwareResetCmd()
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 *            and/or I2C_GenerateStop() in order to clear the error flag and source,
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 *            and return to correct communication status.
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 *
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 *
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 *  2) Advanced state monitoring:
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 *     Using the function I2C_GetLastEvent() which returns the image of both status
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 *     registers in a single word (uint32_t) (Status Register 2 value is shifted left
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 *     by 16 bits and concatenated to Status Register 1).
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 *     - When to use:
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 *       - This function is suitable for the same applications above but it allows to
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 *         overcome the limitations of I2C_GetFlagStatus() function (see below).
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 *         The returned value could be compared to events already defined in the
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 *         library (stm32f10x_i2c.h) or to custom values defined by user.
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 *       - This function is suitable when multiple flags are monitored at the same time.
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 *       - At the opposite of I2C_CheckEvent() function, this function allows user to
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 *         choose when an event is accepted (when all events flags are set and no
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 *         other flags are set or just when the needed flags are set like
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 *         I2C_CheckEvent() function).
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 *     - Limitations:
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 *       - User may need to define his own events.
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 *       - Same remark concerning the error management is applicable for this
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 *         function if user decides to check only regular communication flags (and
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 *         ignores error flags).
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 *
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 *
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 *  3) Flag-based state monitoring:
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 *     Using the function I2C_GetFlagStatus() which simply returns the status of
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 *     one single flag (ie. I2C_FLAG_RXNE ...).
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 *     - When to use:
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 *        - This function could be used for specific applications or in debug phase.
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 *        - It is suitable when only one flag checking is needed (most I2C events
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 *          are monitored through multiple flags).
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 *     - Limitations:
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 *        - When calling this function, the Status register is accessed. Some flags are
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 *          cleared when the status register is accessed. So checking the status
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 *          of one Flag, may clear other ones.
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 *        - Function may need to be called twice or more in order to monitor one
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 *          single event.
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 *
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 */

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 *  1) Basic state monitoring
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 *******************************************************************************
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 */
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/**
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  * @brief  Checks whether the last I2Cx Event is equal to the one passed
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  *   as parameter.
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  * @param  I2Cx: where x can be 1 or 2 to select the I2C peripheral.
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  * @param  I2C_EVENT: specifies the event to be checked.
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  *   This parameter can be one of the following values:
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  *     @arg I2C_EVENT_SLAVE_TRANSMITTER_ADDRESS_MATCHED           : EV1
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  *     @arg I2C_EVENT_SLAVE_RECEIVER_ADDRESS_MATCHED              : EV1
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  *     @arg I2C_EVENT_SLAVE_TRANSMITTER_SECONDADDRESS_MATCHED     : EV1
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  *     @arg I2C_EVENT_SLAVE_RECEIVER_SECONDADDRESS_MATCHED        : EV1
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  *     @arg I2C_EVENT_SLAVE_GENERALCALLADDRESS_MATCHED            : EV1
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  *     @arg I2C_EVENT_SLAVE_BYTE_RECEIVED                         : EV2
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  *     @arg (I2C_EVENT_SLAVE_BYTE_RECEIVED | I2C_FLAG_DUALF)      : EV2
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  *     @arg (I2C_EVENT_SLAVE_BYTE_RECEIVED | I2C_FLAG_GENCALL)    : EV2
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  *     @arg I2C_EVENT_SLAVE_BYTE_TRANSMITTED                      : EV3
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  *     @arg (I2C_EVENT_SLAVE_BYTE_TRANSMITTED | I2C_FLAG_DUALF)   : EV3
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  *     @arg (I2C_EVENT_SLAVE_BYTE_TRANSMITTED | I2C_FLAG_GENCALL) : EV3
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  *     @arg I2C_EVENT_SLAVE_ACK_FAILURE                           : EV3_2
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  *     @arg I2C_EVENT_SLAVE_STOP_DETECTED                         : EV4
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  *     @arg I2C_EVENT_MASTER_MODE_SELECT                          : EV5
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  *     @arg I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED            : EV6
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  *     @arg I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED               : EV6
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  *     @arg I2C_EVENT_MASTER_BYTE_RECEIVED                        : EV7
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  *     @arg I2C_EVENT_MASTER_BYTE_TRANSMITTING                    : EV8
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  *     @arg I2C_EVENT_MASTER_BYTE_TRANSMITTED                     : EV8_2
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  *     @arg I2C_EVENT_MASTER_MODE_ADDRESS10                       : EV9
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  *
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  * @note: For detailed description of Events, please refer to section
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  *    I2C_Events in stm32f10x_i2c.h file.
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  *
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  * @retval An ErrorStatus enumeration value:
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  * - SUCCESS: Last event is equal to the I2C_EVENT
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  * - ERROR: Last event is different from the I2C_EVENT
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  */

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void MPU6050_WriteReg(uint8_t RegAddress,uint8_t Data)
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{
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  /*软件I2C，阻塞式程序
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  MyIIC_Start();
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  MyIIC_SendByte(MPU6050_ADDRESS);
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  MyIIC_ReceiveAck();//可以加判断，确保时序的正确
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  MyIIC_SendByte(RegAddress);//指定要写入的寄存器
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  MyIIC_ReceiveAck();
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  MyIIC_SendByte(Data);
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  MyIIC_ReceiveAck();
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  MyIIC_Stop();
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  */
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  //硬件IIC，非阻塞式程序
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  I2C_GenerateSTART(I2C2,ENABLE);
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  while(I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_MODE_SELECT ) !=SUCCESS);//事件监测
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  I2C_Send7bitAddress(I2C2,MPU6050_ADDRESS,I2C_Direction_Transmitter);//选择I2C外设，从机地址，从机地址最低位。此函数自带接收应答的功能
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  while(I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) !=SUCCESS);
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  I2C_SendData(I2C2,RegAddress);//写入DR，需要等待EV8事件
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  while(I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_BYTE_TRANSMITTING) !=SUCCESS);
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  I2C_SendData(I2C2,Data);
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  while(I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_BYTE_TRANSMITTED) !=SUCCESS);//发送完最后一个字节，需要监测EB8_1事件
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  I2C_GenerateSTOP(I2C2,ENABLE);
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}

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void MPU6050_WaitEvent(I2C_TypeDef* I2Cx, uint32_t I2C_EVENT)
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{
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  uint32_t Timeout;
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  Timeout= 10000;
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  while(I2C_CheckEvent(I2Cx,I2C_EVENT) != SUCCESS)
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  {
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    Timeout--;
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    if(Timeout==0)
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    {
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      break;
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    }
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  }
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}