5.10 I2C Guide

    I2Cx_scl_clk_en();
    I2Cx_sda_clk_en();
    GPIOx->POD |= (I2Cx_SCL_PIN | I2Cx_SDA_PIN);//pull up pin

    GPIO_InitStruct(&GPIO_InitStructure);
    GPIO_InitStructure.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    GPIO_InitStructure.GPIO_Mode  = GPIO_MODE_AF_OD;
    GPIO_InitStructure.GPIO_Alternate = GPIO_AF6;
    GPIO_InitStructure.GPIO_Pull = GPIO_PULL_UP;
    GPIO_InitPeripheral(GPIOx, &GPIO_InitStructure);

    /** I2C periphral configuration */
    I2C_DeInit(I2Cx);
    I2C_InitStruct(&I2C_InitStructure);
    I2C_InitStructure.BusMode     = I2C_BUSMODE_I2C;
    I2C_InitStructure.FmDutyCycle = I2C_FMDUTYCYCLE_2;
    I2C_InitStructure.OwnAddr1    = 0xff;
    I2C_InitStructure.AckEnable   = I2C_ACKEN;
    I2C_InitStructure.AddrMode    = I2C_ADDR_MODE_7BIT;
    I2C_InitStructure.ClkSpeed    = I2C_Speed;
    I2C_Init(I2Cx, &I2C_InitStructure);

    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);

    /** Send START condition */
    I2C_GenerateStart(I2Cx, ENABLE);
    /** Test on EV5 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_MODE_FLAG))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** Send EEPROM address for write */
    I2C_SendAddr7bit(I2Cx, EEPROM_ADDRESS, I2C_DIRECTION_SEND);
    /** Test on EV6 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_TXMODE_FLAG))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** Send the EEPROM's internal address to write to */
    I2C_SendData(I2Cx, WriteAddr);
    /** Test on EV8 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_DATA_SENDED))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** While there is data to be written */
    while (NumByteToWrite--)
    {
        /** Send the current byte */
        I2C_SendData(I2Cx, *pBuffer);
        /** Point to the next byte to be written */
        pBuffer++;
        /** Test on EV8 and clear it */
        sEETimeout = sEE_LONG_TIMEOUT;
        while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_DATA_SENDED))
        {
            if ((sEETimeout--) == 0)
            {
                sEE_TIMEOUT_UserCallback();
                return;
            }
        }
    }
    /** Send STOP condition */
    I2C_GenerateStop(I2Cx, ENABLE);
    I2C_EE_WaitEepromStandbyState();
    I2C_EE_WriteOnePageCompleted();

    I2C_ConfigPecLocation(I2Cx, I2C_PEC_POS_CURRENT);
    I2C_ConfigAck(I2Cx, ENABLE);

    /** Send START condition */
    I2C_GenerateStart(I2Cx, ENABLE);

    /** Test on EV5 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_MODE_FLAG))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** Send EEPROM address for write */
    I2C_SendAddr7bit(I2Cx, EEPROM_ADDRESS, I2C_DIRECTION_SEND);
    /** Test on EV6 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_TXMODE_FLAG))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** Clear EV6 by setting again the PE bit */
    I2C_Enable(I2Cx, ENABLE);
    /** Send the EEPROM's internal address to write to */
    I2C_SendData(I2Cx, ReadAddr);
    /** Test on EV8 and clear it */
    sEETimeout = sEE_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_DATA_SENDED))
    {
        if ((sEETimeout--) == 0)
        {
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }
    /** Send STRAT condition a second time */
    I2C_GenerateStart(I2Cx, ENABLE);

    /** Keep looping till the slave acknowledge his address or maximum number
       of trials is reached (this number is defined by sEE_MAX_TRIALS_NUMBER) */
    while (1)
    {
        /** Send START condition */
        I2C_GenerateStart(I2Cx, ENABLE);

        /** Test on EV5 and clear it */
        sEETimeout = sEE_LONG_TIMEOUT;
        while (!I2C_CheckEvent(I2Cx, I2C_EVT_MASTER_MODE_FLAG))
        {
            if ((sEETimeout--) == 0)
            {
                sEE_TIMEOUT_UserCallback();
                return;
            }
        }

        /** Send EEPROM address for write */
        I2C_SendAddr7bit(I2Cx, EEPROM_ADDRESS, I2C_DIRECTION_SEND);
        /** Wait for ADDR flag to be set (Slave acknowledged his address) */
        sEETimeout = sEE_LONG_TIMEOUT;
        do
        {
            /** Get the current value of the STS1 register */
            tmpSR1 = I2Cx->STS1;

            /** Update the timeout value and exit if it reach 0 */
            if ((sEETimeout--) == 0)
                sEE_TIMEOUT_UserCallback();
        }
        /** Keep looping till the Address is acknowledged or the AF flag is
           set (address not acknowledged at time) */
        while ((tmpSR1 & (I2C_STS1_ADDRF | I2C_STS1_ACKFAIL)) == 0);

        /** Check if the ADDR flag has been set */
        if (tmpSR1 & I2C_STS1_ADDRF)
        {
            /** Clear ADDR Flag by reading STS1 then STS2 registers (STS1 have already
               been read) */
            (void)I2Cx->STS2;

            /** STOP condition */
            I2C_GenerateStop(I2Cx, ENABLE);

            /** Exit the function */
            return;
        }
        else
        {
            /** Clear AF flag */
            I2C_ClrFlag(I2Cx, I2C_FLAG_ACKFAIL);
        }

        /** Check if the maximum allowed numbe of trials has bee reached */
        if (sEETrials++ == sEE_MAX_TRIALS_NUMBER)
        {
            /** If the maximum number of trials has been reached, exit the function */
            sEE_TIMEOUT_UserCallback();
            return;
        }
    }

    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_I2C1, ENABLE);
    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_GPIO, ENABLE);
    GPIOx->POD |= (I2Cx_SCL_PIN | I2Cx_SDA_PIN);//pull up pin

    GPIO_InitStruct(&i2c1_gpio);
    /*PB10 -- SCL; PB11 -- SDA*/
    i2c1_gpio.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    i2c1_gpio.GPIO_Mode  = GPIO_MODE_AF_OD;
    i2c1_gpio.GPIO_Alternate = GPIO_AF_I2C;
    i2c1_gpio.GPIO_Pull = GPIO_PULL_UP;
    GPIO_InitPeripheral(GPIOx, &i2c1_gpio);

    I2C_DeInit(I2Cx);
    I2C_InitStruct(&i2c1_master);
    i2c1_master.BusMode     = I2C_BUSMODE_I2C;
    i2c1_master.FmDutyCycle = I2C_FMDUTYCYCLE_2; //if the spped greater than 400KHz, the FmDutyCycle mast be configured to I2C_FMDUTYCYCLE_2
    i2c1_master.OwnAddr1    = I2C_MASTER_ADDR;
    i2c1_master.AckEnable   = I2C_ACKEN;
    i2c1_master.AddrMode    = I2C_ADDR_MODE_7BIT;
    i2c1_master.ClkSpeed    = 100000;

    I2C_Init(I2Cx, &i2c1_master);

    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);

    I2C_Enable(I2Cx, ENABLE);

    I2CTimeout             = I2CT_LONG_TIMEOUT;
    while (I2C_GetFlag(I2C1, I2C_FLAG_BUSY))
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_BUSY);
            return 1;
        }
    }

    if (Comm_Flag == C_READY)
    {
        Comm_Flag = C_START_BIT;
        I2C_GenerateStart(I2C1, ENABLE);
    }

    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_MODE_FLAG)) // EV5
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_MODE);
            return 1;
        }
    }

    I2C_SendAddr7bit(I2C1, I2C_SLAVE_ADDR, I2C_DIRECTION_SEND);
    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_TXMODE_FLAG)) // EV6
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_TXMODE);
            return 1;
        }
    }
    Comm_Flag = C_READY;

    // send data
    while (len-- > 0)
    {
        I2C_SendData(I2C1, *sendBufferPtr++);
        I2CTimeout = I2CT_LONG_TIMEOUT;
        while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_DATA_SENDING)) // EV8
        {
            if ((I2CTimeout--) == 0)
            {
                CommTimeOut_CallBack(MASTER_SENDING);
                return 1;
            }
        }
    }

    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_DATA_SENDED)) // EV8-2
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_SENDED);
            return 1;
        }
    }

    if (Comm_Flag == C_READY)
    {
        Comm_Flag = C_STOP_BIT;
        I2C_GenerateStop(I2C1, ENABLE);
    }

    if (len == 1)
    {
        I2C_ConfigAck(I2C1, DISABLE);
        (void)(I2C1->STS1); /// clear ADDR
        (void)(I2C1->STS2);
        if (Comm_Flag == C_READY)
        {
            Comm_Flag = C_STOP_BIT;
            I2C_GenerateStop(I2C1, ENABLE);
        }

        I2CTimeout = I2CT_LONG_TIMEOUT;
        while (!I2C_GetFlag(I2C1, I2C_FLAG_RXDATNE))
        {
            if ((I2CTimeout--) == 0)
            {
                CommTimeOut_CallBack(MASTER_RECVD);
                return 1;
            }
        }
        *recvBufferPtr++ = I2C_RecvData(I2C1);
        len--;
    }
    else if (len == 2)
    {
        I2C_ConfigNackLocation(I2C1, I2C_NACK_POS_NEXT);
        (void)(I2C1->STS1);
        (void)(I2C1->STS2);
        I2C_ConfigAck(I2C1, DISABLE);

void IIC_SWReset(void)
{
    GPIO_InitType i2cx_gpio;

    GPIO_InitStruct(&i2cx_gpio);
    i2cx_gpio.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    i2cx_gpio.GPIO_Mode  = GPIO_MODE_INPUT;
    GPIO_InitPeripheral(GPIOx, &i2cx_gpio);

    I2CTimeout = I2CT_LONG_TIMEOUT;
    for (;;)
    {
        if ((I2Cx_SCL_PIN | I2Cx_SDA_PIN) == (GPIOx->PID & (I2Cx_SCL_PIN | I2Cx_SDA_PIN)))
        {
            I2C_EnableSoftwareReset(I2Cx,ENABLE);
            __NOP();
            __NOP();
            __NOP();
            __NOP();
            __NOP();
            I2C_EnableSoftwareReset(I2Cx,DISABLE);

            log_info("***** IIC module self reset! *****\r\n");
            break;
        }
        else
        {
            if ((I2CTimeout--) == 0)
            {
                IIC_RCCReset();
            }
        }
    }
}

    I2C_DeInit(I2Cx);
    I2C_InitStruct(&i2c1_master);
    i2c1_master.BusMode     = I2C_BUSMODE_I2C;
    i2c1_master.FmDutyCycle = I2C_FMDUTYCYCLE_2;
    i2c1_master.OwnAddr1    = I2C_MASTER_ADDR;
    i2c1_master.AckEnable   = I2C_ACKEN;
    i2c1_master.AddrMode    = I2C_ADDR_MODE_7BIT;
    i2c1_master.ClkSpeed    = 100000; // 100000 100K

    I2C_Init(I2Cx, &i2c1_master);
    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);
    // int enable
    I2C_ConfigInt(I2Cx, I2C_INT_EVENT | I2C_INT_BUF | I2C_INT_ERR, ENABLE);
    NVIC_ConfigurationMaster(1);
    I2C_Enable(I2Cx, ENABLE);
    return 0;

void NVIC_ConfigurationMaster(uint8_t ch)
{
    NVIC_InitType NVIC_InitStructure;
    if (ch == 1)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C1_EV_IRQn;
    }
    if (ch == 2)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C2_EV_IRQn;
    }
    NVIC_InitStructure.NVIC_IRQChannelPriority           = 2;
    NVIC_InitStructure.NVIC_IRQChannelCmd                = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    if (ch == 1)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C1_ER_IRQn;
    }
    if (ch == 2)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C2_ER_IRQn;
    }
    NVIC_InitStructure.NVIC_IRQChannelPriority           = 3;
    NVIC_InitStructure.NVIC_IRQChannelCmd                = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void I2C1_EV_IRQHandler(void)
{
    uint32_t last_event = 0;

    last_event = I2C_GetLastEvent(I2C1);
    if ((last_event & I2C_ROLE_MASTER) == I2C_ROLE_MASTER) // master mode
    {
        switch (last_event)
        {
        case I2C_EVT_MASTER_MODE_FLAG: // EV5 Send addr

            if(flag_trans_direct)     // read
            {
                Memset(rx_buf, 0, TEST_BUFFER_SIZE); // clear recv buf, ready to recv data
                I2C_SendAddr7bit(I2C1, I2C_SLAVE_ADDR, I2C_DIRECTION_RECV);
                rx_num = 0;
            }
            else // write
            {
                I2C_SendAddr7bit(I2C1, I2C_SLAVE_ADDR, I2C_DIRECTION_SEND);
                tx_num = 0;
            }
            break;

           // MasterTransmitter
        case I2C_EVT_MASTER_TXMODE_FLAG: // EV6 Send first data
            Comm_Flag = C_READY;
            I2C_SendData(I2C1, tx_buf[tx_num++]);
            break;

        case I2C_EVT_MASTER_DATA_SENDING: // EV8 Sending data

            if (tx_num < TEST_BUFFER_SIZE)
            {
                I2C_SendData(I2C1, tx_buf[tx_num++]);
            }
            break;

        case I2C_EVT_MASTER_DATA_SENDED: // EV8_2 Send finish

            if (tx_num == TEST_BUFFER_SIZE)
            {
                if (Comm_Flag == C_READY)
                {
                    Comm_Flag = C_STOP_BIT;
                    I2C_GenerateStop(I2C1, ENABLE);
                    flag_master_send_finish = 1;
                }
            }
            break;

            // MasterReceiver
        case I2C_EVT_MASTER_RXMODE_FLAG: // EV6
            Comm_Flag = C_READY;
            if (TEST_BUFFER_SIZE == 1)
            {
                I2C_ConfigAck(I2C1, DISABLE);
                if (Comm_Flag == C_READY)
                {
                    Comm_Flag = C_STOP_BIT;
                    I2C_GenerateStop(I2C1, ENABLE);
                }
            }
            else if (TEST_BUFFER_SIZE == 2)
            {
                I2C1->CTRL1 |= I2C_NACK_POS_NEXT; /// set ACKPOS
                I2C_ConfigAck(I2C1, DISABLE);
            }
            break;

        case I2C_EVT_MASTER_DATA_RECVD_FLAG: // EV7.one byte recved
        case I2C_EVT_MASTER_DATA_RECVD_BSF_FLAG: // EV7.When the I2C communication rate is too high, BSF = 1

            rx_buf[rx_num++] = I2C_RecvData(I2C1);
            if (rx_num == (TEST_BUFFER_SIZE - 1))
            {
                I2C_ConfigAck(I2C1, DISABLE);   // Disable I2C1 acknowledgement.
                if (Comm_Flag == C_READY)
                {
                    Comm_Flag = C_STOP_BIT;
                    I2C_GenerateStop(I2C1, ENABLE); // Send I2C1 STOP Condition.
                }
            }
            else if (rx_num == TEST_BUFFER_SIZE)
            {
                flag_master_recv_finish = 1;
            }
            break;
        case 0x00030201: // Arbitration lost
        case 0x00030101: // Acknowledge failure
        case 0x00030501: // Acknowledge failure and Bus error
            I2C_Enable(I2C1, DISABLE);
            I2C_Enable(I2C1, ENABLE);
            break;

        default:
            log_info("I2C error status:0x%x\r\n", last_event);
            break;
        }
    }
}

void I2C1_ER_IRQHandler(void)
{
   if(I2C_GetFlag(I2C1, I2C_FLAG_ACKFAIL))
   {
      I2C_ClrFlag(I2C1, I2C_FLAG_ACKFAIL);
      I2C_GenerateStop(I2C1, ENABLE); // Send I2C1 STOP Condition.
   }
}

    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_I2C1, ENABLE);
    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_GPIO, ENABLE);
    GPIOx->POD |= (I2Cx_SCL_PIN | I2Cx_SDA_PIN);//pull up pin

    GPIO_InitStruct(&i2c1_gpio);
    /*PB10 -- SCL; PB11 -- SDA*/
    i2c1_gpio.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    i2c1_gpio.GPIO_Mode  = GPIO_MODE_AF_OD;
    i2c1_gpio.GPIO_Alternate = GPIO_AF_I2C;
    i2c1_gpio.GPIO_Pull = GPIO_PULL_UP;
    GPIO_InitPeripheral(GPIOx, &i2c1_gpio);

    I2C_DeInit(I2Cx);
    I2C_InitStruct(&i2c1_master);
    i2c1_master.BusMode     = I2C_BUSMODE_I2C;
    i2c1_master.FmDutyCycle = I2C_FMDUTYCYCLE_2; //if the spped greater than 400KHz, the FmDutyCycle mast be configured to I2C_FMDUTYCYCLE_2
    i2c1_master.OwnAddr1    = I2C_MASTER_ADDR;
    i2c1_master.AckEnable   = I2C_ACKEN;
    i2c1_master.AddrMode    = I2C_ADDR_MODE_7BIT;
    i2c1_master.ClkSpeed    = 100000;

    I2C_Init(I2Cx, &i2c1_master);

    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);

    I2C_Enable(I2Cx, ENABLE);
    return 0;

    if (Comm_Flag == C_READY)
    {
        Comm_Flag = C_START_BIT;
        I2C_GenerateStart(I2C1, ENABLE);
    }

    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_MODE_FLAG)) // EV5
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_MODE);
            return 1;
        }
    }

    I2C_SendAddr7bit(I2C1, addr, I2C_DIRECTION_SEND);
    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_TXMODE_FLAG)) // EV6
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_TXMODE);
            return 1;
        }
    }
    Comm_Flag = C_READY;

    if (Comm_Flag == C_READY)
    {
        Comm_Flag = C_START_BIT;
        I2C_GenerateStart(I2C1, ENABLE);
    }

    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_MODE_FLAG)) // EV5
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_MODE);
            return 1;
        }
    }
    // send addr
    I2C_SendAddr7bit(I2C1, addr, I2C_DIRECTION_RECV);
    I2CTimeout = I2CT_LONG_TIMEOUT;
    while (!I2C_CheckEvent(I2C1, I2C_EVT_MASTER_RXMODE_FLAG)) // EV6
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(MASTER_RXMODE);
            return 1;
        }
    }
    Comm_Flag = C_READY;

    if (len == 1)
    {
        I2C_ConfigAck(I2C1, DISABLE);
        (void)(I2C1->STS1); /// clear ADDR
        (void)(I2C1->STS2);

    i2c_master_init();

    /* Fill the buffer to send */
    for (i = 0; i < TEST_BUFFER_SIZE; i++)
    {
        tx_buf[i] = i;
    }

     /* First write in the memory followed by a read of the written data --------*/
    /* Write data*/
    i2c_master_send(tx_buf, TEST_BUFFER_SIZE, I2C_SLAVE_ADDR_1);

    /* Read data */
    i2c_master_recv(rx_buf, TEST_BUFFER_SIZE, I2C_SLAVE_ADDR_1);

    /* Check if the data written to the memory is read correctly */
    test_status = Buffercmp(tx_buf, rx_buf, TEST_BUFFER_SIZE);
    if (test_status == PASSED)
    {
        log_info("write and read data the same, i2c master addr1 test pass\r\n");

    }
    else
    {
        log_info("write and read data are different, i2c master addr1 test fail\r\n");
    }
    /* test_status = PASSED, if the write and read data are the same  */
    /* test_status = FAILED, if the write and read data are different */

    /* delay  */
    for (i = 0; i < 5000; i++);

    /* Empty the rx buffer  */
    for (i = 0; i < TEST_BUFFER_SIZE; i++)
    {
        rx_buf[i] = 0;
    }
    /* First write in the memory followed by a read of the written data --------*/
    /* Write data*/
    i2c_master_send(tx_buf, TEST_BUFFER_SIZE, I2C_SLAVE_ADDR_2);

    /* Read data */
    i2c_master_recv(rx_buf, TEST_BUFFER_SIZE, I2C_SLAVE_ADDR_2);

    /* Check if the data written to the memory is read correctly */
    test_status = Buffercmp(tx_buf, rx_buf, TEST_BUFFER_SIZE);

    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_I2C1, ENABLE);
    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_GPIO, ENABLE);
    GPIOx->POD |= (I2Cx_SCL_PIN | I2Cx_SDA_PIN);//pull up pin
    GPIO_InitStruct(&i2c1_gpio);
    /*PB10 -- SCL; PB11 -- SDA*/
    i2c1_gpio.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    i2c1_gpio.GPIO_Mode  = GPIO_MODE_AF_OD;
    i2c1_gpio.GPIO_Alternate = GPIO_AF_I2C;
    GPIO_InitPeripheral(GPIOx, &i2c1_gpio);

    I2C_DeInit(I2Cx);
    I2C_InitStruct(&i2c1_slave);
    i2c1_slave.BusMode     = I2C_BUSMODE_I2C;
    i2c1_slave.FmDutyCycle = I2C_FMDUTYCYCLE_2;   //if the spped greater than 400KHz, the FmDutyCycle mast be configured to I2C_FMDUTYCYCLE_2
    i2c1_slave.OwnAddr1    = I2C_SLAVE_ADDR;
    i2c1_slave.AckEnable   = I2C_ACKEN;
    i2c1_slave.AddrMode    = I2C_ADDR_MODE_7BIT;
    i2c1_slave.ClkSpeed    = 100000;

    I2C_Init(I2Cx, &i2c1_slave);

    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);

    I2C_Enable(I2Cx, ENABLE);

int i2c_slave_send(uint8_t* data, int len)
{
    uint32_t lastevent;
    uint8_t* sendBufferPtr = data;
    I2CTimeout = I2CT_LONG_TIMEOUT*10;

    while (!I2C_CheckEvent(I2C1, I2C_EVT_SLAVE_SEND_ADDR_MATCHED))/* send addr matched */
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(SLAVE_MODE);
            return 1;
        }
    }
    I2CTimeout = I2CT_LONG_TIMEOUT;


    I2C_Enable(I2C1, ENABLE);
    I2C_SendData(I2C1, *sendBufferPtr++);
    while (1)
    {
        lastevent = I2C_GetLastEvent(I2C1);
        if (lastevent == I2C_EVT_SLAVE_DATA_SENDED)
        {
            I2C_SendData(I2C1, *sendBufferPtr++);
            I2CTimeout = I2CT_LONG_TIMEOUT;
        }
        else if ((lastevent == I2C_EVT_SLAVE_ACK_MISS) || (lastevent == I2C_EVT_SLAVE_STOP_RECVD))
        {
            I2C_ClrFlag(I2C1, I2C_FLAG_ACKFAIL);
            I2C_Enable(I2C1, ENABLE);
            break;
        }
        else if ((lastevent & 0x00000400) == 0x00000400)
        {
            CommTimeOut_CallBack(SLAVE_BUSERR);
            return 1;
        }
        else
        {
            if ((I2CTimeout--) == 0)
            {
                CommTimeOut_CallBack(SLAVE_UNKNOW);
                return 1;
            }
        }
    }

int i2c_slave_recv(uint8_t* data, uint32_t rcv_len)
{
    uint32_t lastevent;
    rxDataNum = 0;
    I2CTimeout = I2CT_LONG_TIMEOUT*10;

    while (!I2C_CheckEvent(I2C1, I2C_EVT_SLAVE_RECV_ADDR_MATCHED))/* receive addr matched */
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(SLAVE_MODE);
            return 1;
        }
    }
    I2CTimeout = I2CT_LONG_TIMEOUT;

    I2C_Enable(I2C1, ENABLE);
    while (1)
    {
        lastevent = I2C_GetLastEvent(I2C1);
        if (lastevent == I2C_EVT_SLAVE_DATA_RECVD)
        {
            *data++ = I2C_RecvData(I2C1);
            rxDataNum++;
            I2CTimeout = I2CT_LONG_TIMEOUT;
        }
        else if (lastevent == I2C_EVT_SLAVE_STOP_RECVD)
        {
            I2C_Enable(I2C1, ENABLE);
            break;
        }
        else if ((lastevent & 0x00000400) == 0x00000400)
        {
            CommTimeOut_CallBack(SLAVE_BUSERR);
            return 1;
        }
        else
        {
            if ((I2CTimeout--) == 0)
            {
                CommTimeOut_CallBack(SLAVE_UNKNOW);
                return 1;
            }
        }
    }

    return 0;

int main(void)
{
    uint16_t i = 0;

    log_init();
    log_info("this is a i2c slave test demo\r\n");
    /* Initialize the I2C EEPROM driver ----------------------------------------*/
    i2c_slave_init();
    while (1)
    {
        for(; ;)
        {
            /* Read data */
            if(i2c_slave_recv(data_buf, TEST_BUFFER_SIZE))
            {
                break;  /* receive fail, reaccept*/
            }

            /* Write data*/
            if(i2c_slave_send(data_buf, TEST_BUFFER_SIZE))
            {
                break;  /* send fail, reaccept*/
            }
            for (i = 0; i < TEST_BUFFER_SIZE; i++)
            {
                data_buf[i] = 0;
            }
        }
    }
}

int i2c_slave_init(void)
{
    I2C_InitType i2c1_slave;
    GPIO_InitType i2c1_gpio;
    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_I2C1, ENABLE);
    RCC_EnableAPBPeriphClk(RCC_APB_PERIPH_GPIO, ENABLE);
    GPIOx->POD |= (I2Cx_SCL_PIN | I2Cx_SDA_PIN);//pull up pin

    GPIO_InitStruct(&i2c1_gpio);
    /*PB10 -- SCL; PB11 -- SDA*/
    i2c1_gpio.Pin        = I2Cx_SCL_PIN | I2Cx_SDA_PIN;
    i2c1_gpio.GPIO_Mode  = GPIO_MODE_AF_OD;
    i2c1_gpio.GPIO_Alternate = GPIO_AF_I2C;
    GPIO_InitPeripheral(GPIOx, &i2c1_gpio);

    I2C_DeInit(I2Cx);
    I2C_InitStruct(&i2c1_slave);
    i2c1_slave.BusMode     = I2C_BUSMODE_I2C;
    i2c1_slave.FmDutyCycle = I2C_FMDUTYCYCLE_2;
    i2c1_slave.OwnAddr1    = I2C_SLAVE_ADDR;
    i2c1_slave.AckEnable   = I2C_ACKEN;
    i2c1_slave.AddrMode    = I2C_ADDR_MODE_7BIT;
    i2c1_slave.ClkSpeed    = 100000; // 100000 100K

    I2C_Init(I2Cx, &i2c1_slave);
    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);
    // int enable
    I2C_ConfigInt(I2Cx, I2C_INT_EVENT | I2C_INT_BUF | I2C_INT_ERR, ENABLE);
    NVIC_ConfigurationSlave((uint8_t)1);
    I2C_Enable(I2Cx, ENABLE);
    return 0;

void NVIC_ConfigurationSlave(uint8_t ch)
{
    NVIC_InitType NVIC_InitStructure;
    if (ch == 1)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C1_EV_IRQn;
    }
    if (ch == 2)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C2_EV_IRQn;
    }
    NVIC_InitStructure.NVIC_IRQChannelPriority           = 2;
    NVIC_InitStructure.NVIC_IRQChannelCmd                = ENABLE;
    NVIC_Init(&NVIC_InitStructure);

    if (ch == 1)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C1_ER_IRQn;
    }
    if (ch == 2)
    {
        NVIC_InitStructure.NVIC_IRQChannel = I2C2_ER_IRQn;
    }
    NVIC_InitStructure.NVIC_IRQChannelPriority           = 3;
    NVIC_InitStructure.NVIC_IRQChannelCmd                = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
}

void I2C1_EV_IRQHandler(void)
{
    uint8_t timeout_flag = 0;
    uint32_t last_event = 0;

    last_event = I2C_GetLastEvent(I2C1);
    if ((last_event & I2C_ROLE_MASTER) != I2C_ROLE_MASTER) // MSMODE = 0:I2C slave mode
    {
        switch (last_event)
        {
        case I2C_EVT_SLAVE_RECV_ADDR_MATCHED: //EV1 Rx addr matched

            // clear flag,ready to receive data
            rxDataNum = 0;
            break;

        case I2C_EVT_SLAVE_SEND_ADDR_MATCHED: //EV1 Tx addr matched

            rxDataNum = 0;
            I2C1->DAT = data_buf[rxDataNum++];// Send first data
            break;

        // SlaveTransmitter
        case I2C_EVT_SLAVE_DATA_SENDING:  //EV3 Sending data

            break;

        case I2C_EVT_SLAVE_DATA_SENDED:
            I2C1->DAT = data_buf[rxDataNum++];
            break;

        // SlaveReceiver
        case I2C_EVT_SLAVE_DATA_RECVD: //EV2 one byte recved
            data_buf[rxDataNum++] = I2C1->DAT;
            break;


        case I2C_EVT_SLAVE_STOP_RECVD: // EV4
            I2C_Enable(I2C1, ENABLE);
            if(rxDataNum != 0)
            {
                flag_slave_recv_finish = 1; // The STOPF bit is not set after a NACK reception
            }
            break;

        default:
            I2C_Enable(I2C1, ENABLE);
            timeout_flag = 1;
            break;
        }
    }

    if (timeout_flag)
    {
        if ((I2CTimeout--) == 0)
        {
            CommTimeOut_CallBack(SLAVE_UNKNOW);
        }
    }
    else
    {
        I2CTimeout = I2CT_LONG_TIMEOUT;
    }

void I2C1_ER_IRQHandler(void)
{
    uint32_t last_event;
    last_event = I2C_GetLastEvent(I2C1);
    if(last_event == I2C_EVT_SLAVE_ACK_MISS)
    {
        I2C_ClrFlag(I2C1, I2C_FLAG_ACKFAIL);
        if(rxDataNum != 0)  //slave send the last data and recv NACK
        {
            flag_slave_send_finish = 1;
        }
        else //not the last data recv nack, send fail
        {
        }
    }
    else if(last_event == 0x601D0 || last_event == 0x601C0)
    {
        CommTimeOut_CallBack(SLAVE_UNKNOW);
    }
}

    I2C_Init(I2Cx, &i2c1_slave);

    I2C_EnableTimeoutDetect(I2Cx, I2C_TIMEOUT_LOW, DISABLE);
    I2C_ConfigOwnAddr2(I2C1,I2C_SLAVE_ADDR_2);
    I2C_EnableDualAddr(I2C1,ENABLE);

    I2C_Enable(I2Cx, ENABLE);

    if(addr == 0)
    {
        while (!I2C_CheckEvent(I2C1, I2C_EVT_SLAVE_SEND_ADDR_MATCHED))/* send addr1 matched */
        {
        }
    }
    else
    {
        while (!I2C_CheckEvent(I2C1, I2C_EVT_SLAVE_SEND_ADDR2_MATCHED))/* send addr2 matched */
        {
        }
    }

    I2C_Enable(I2C1, ENABLE);
    while (Numbytetoread != 0)
    {
        I2CTimeout = I2CT_LONG_TIMEOUT;
        while (!I2C_CheckEvent(I2C1, I2C_EVT_SLAVE_DATA_RECVD))
        {
            if ((I2CTimeout--) == 0)
            {
                    CommTimeOut_CallBack(SLAVE_MODE);
                    return 1;
            }
        }
        *data++ = I2C_RecvData(I2C1);
        Numbytetoread--;
    }

        /* Read data */
        i2c_slave_recv(data_buf, TEST_BUFFER_SIZE, 0);

        /* Write data*/
        i2c_slave_send(data_buf, TEST_BUFFER_SIZE, 0);


        /* address 2 */
        /* Read data */
        i2c_slave_recv(data_buf, TEST_BUFFER_SIZE, 1);

        /* Write data*/
        i2c_slave_send(data_buf, TEST_BUFFER_SIZE, 1);
    }