江科大学习笔记 _13.硬件IIC

第一步：配置IIC外设，代替IIC_Init()

第二步：控制外设电路，实现指定地址写时序，替换Write_Reg()

第三步：控制外设电路，实现指定地址读时序，替换Read_Reg()

 

RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C2,ENABLE);//时钟

    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB,ENABLE);

 

    GPIO_InitTypeDef GPIO_InitStruct;

    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_OD;

    GPIO_InitStruct.GPIO_Pin = IIC_SCL|IIC_SDA;

    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;

    GPIO_Init(IIC_Port,&GPIO_InitStruct);//GPIO配置

    

    I2C_InitTypeDef I2C_InitStruct;

    I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;

    I2C_InitStruct.I2C_ClockSpeed = 400000;

    I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;

    I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;

    I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;

    I2C_InitStruct.I2C_OwnAddress1 = 0x00;

    I2C_Init(I2C2,&I2C_InitStruct);//IIC配置

 

    I2C_Cmd(I2C2, ENABLE);

 

 

 

 

 

主机发送

 

I2C_GenerateSTART(I2C2,ENABLE);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS) ;

 

    I2C_Send7bitAddress(I2C2, MPU6050_ADDRESS, I2C_Direction_Transmitter);

 while(I2C_CheckEvent(I2C2,I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)!=SUCCESS);

 

    I2C_SendData(I2C2, RegAddress);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTING) != SUCCESS);

 

    I2C_SendData(I2C2, Data);

     while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED) != SUCCESS);

 

    I2C_GenerateSTOP(I2C2,ENABLE);

 

 

 

 

 

 

 

 

 

 

 

 

 

主机接收

 

I2C_GenerateSTART(I2C2,ENABLE);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS);

 

    I2C_Send7bitAddress(I2C2, MPU6050_ADDRESS, I2C_Direction_Transmitter);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED) != SUCCESS);

 

    I2C_SendData(I2C2, RegAddress);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED) != SUCCESS);

 

    I2C_GenerateSTART(I2C2,ENABLE);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT) != SUCCESS);

 

    I2C_Send7bitAddress(I2C2, MPU6050_ADDRESS, I2C_Direction_Receiver);

    while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED) != SUCCESS);

 

            I2C_AcknowledgeConfig(I2C2,DISABLE);//只接收一字节数据，ACK不给应答

            I2C_GenerateSTOP(I2C2,ENABLE);

 

            while(I2C_CheckEvent(I2C2, I2C_EVENT_MASTER_BYTE_RECEIVED) != SUCCESS);

            Data = I2C_ReceiveData(I2C2);

//如果要接收多字节，for循环这4行,前面两行接收前面的字节,后两行接收最后一个字节

 

    I2C_AcknowledgeConfig(I2C2,ENABLE);

 

阻塞式等待容易导致程序一直在while循环中，程序卡死

所以需要对while等待处理

 

把判断标志位的函数封装进下面函数中，加入超时退出

void MPU6050_WaitEvent(I2C_TypeDef *I2Cx, uint32_t I2C_EVENT)

{

    uint32_t Timeout;

    Timeout = 10000;

 

    while(I2C_CheckEvent(I2Cx, I2C_EVENT) != SUCCESS)

    {

        Timeout--;

        if(Timeout == 0)

        {

            //错误处理操作

            break;

        }

    }

}

 

 

下面是改进之后的等待判断标志位

void MPU6050_WriteReg(uint8_t RegAddress, uint8_t Data)

{

    I2C_GenerateSTART(I2C2,ENABLE);

    MPU6050_WaitEvent(I2C2, I2C_EVENT_MASTER_MODE_SELECT);

 

    I2C_Send7bitAddress(I2C2, MPU6050_ADDRESS, I2C_Direction_Transmitter);

    MPU6050_WaitEvent(I2C2, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED);

 

    I2C_SendData(I2C2, RegAddress);

    MPU6050_WaitEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTING);

 

    I2C_SendData(I2C2, Data);

    MPU6050_WaitEvent(I2C2, I2C_EVENT_MASTER_BYTE_TRANSMITTED);

 

    I2C_GenerateSTOP(I2C2,ENABLE);

}