关于F415硬件I2C

static I2C_StatusType I2C_WaitOnFlagUntilTimeout(I2C_Type *I2Cx, uint32_t Flag, FlagStatus Status, uint32_t EventCheck, uint32_t Timeout)

{

    /* delay 10 us = ms * 100 */

    Timeout *= 100;

    while (I2C_GetFlagStatus(I2Cx, Flag) == Status)

    {

        if (EventCheck & I2C_EVT_CHECK_ACKFAIL)

        {

            if (I2C_GetFlagStatus(I2Cx, I2C_FLAG_ACKFAIL) == SET)

            {

                I2C_GenerateSTOP(I2Cx, ENABLE);

                I2C_ClearFlag(I2Cx, I2C_FLAG_ACKFAIL);

                return I2C_ERROR;

            }

        }

        if (EventCheck & I2C_EVT_CHECK_STOP)

        {

            if (I2C_GetFlagStatus(I2Cx, I2C_FLAG_STOPF) == SET)

            {

                I2C_ClearSTOPFlag(I2Cx);

                return I2C_ERROR;

            }

        }

        I2C_Delay(10);

        if ((Timeout--) == 0)

        {

            return I2C_TIMEOUT;

        }

    }

    return I2C_OK;

}



I2C_StatusType hw_i2c_read_reg(I2C_Type *I2Cx, uint8_t slave_addr, uint8_t reg, uint8_t *rd_value, uint32_t Timeout)

{

    /* Wait until BUSY flag is reset */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_BUSYF, SET, I2C_EVT_CHECK_NONE, I2C_TIMEOUT_BUSY_FLAG) != I2C_OK)

    {

        return I2C_ERROR_STEP_1;

    }



    /* Disable Pos */

    I2C_NACKPositionConfig(I2Cx, I2C_NACKPosition_Current);



    /* Enable Acknowledge */

    I2C_AcknowledgeConfig(I2Cx, ENABLE);



    /* Send START condition */

    I2C_GenerateSTART(I2Cx, ENABLE);



    /* Wait until SB flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_STARTF, RESET, I2C_EVT_CHECK_NONE, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_2;

    }



    /* Send slave address for write */

    I2C_Send7bitAddress(I2Cx, slave_addr, I2C_Direction_Transmit);



    /* Wait until ADDR flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_ADDRF, RESET, I2C_EVT_CHECK_NONE, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_3;

    }



    /* Clear ADDR flag */

    I2C_ClearADDRFlag(I2Cx);



    /* Wait until TDE flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_TDE, RESET, I2C_EVT_CHECK_NONE, Timeout) != I2C_OK)

    {

        /* Send STOP Condition  */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_4;

    }



    /* Send Memory Address */

    I2C_SendData(I2Cx, reg);



    /* Wait until TDE flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_TDE, RESET, I2C_EVT_CHECK_ACKFAIL, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_5;

    }



    /* Send START condition */

    I2C_GenerateSTART(I2Cx, ENABLE);



    /* Wait until SB flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_STARTF, RESET, I2C_EVT_CHECK_NONE, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_6;

    }



    /* Send slave address for read */

    I2C_Send7bitAddress(I2Cx, slave_addr, I2C_Direction_Receive);



    /* Wait until ADDR flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_ADDRF, RESET, I2C_EVT_CHECK_ACKFAIL, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_7;

    }



    /* Disable Acknowledge */

    I2C_AcknowledgeConfig(I2Cx, DISABLE);



    /* Clear ADDR flag */

    I2C_ClearADDRFlag(I2Cx);



    /* Send STOP Condition */

    I2C_GenerateSTOP(I2Cx, ENABLE);



    /* Wait until RXNE flag is set */

    if (I2C_WaitOnFlagUntilTimeout(I2Cx, I2C_FLAG_RDNE, RESET, I2C_EVT_CHECK_NONE, Timeout) != I2C_OK)

    {

        /* Send STOP Condition */

        I2C_GenerateSTOP(I2Cx, ENABLE);

        return I2C_ERROR_STEP_8;

    }



    /* Read data from DR */

    (*rd_value) = I2C_ReceiveData(I2Cx);



    return I2C_OK;

}