基于stm32的i2c代码

以下是基于STM32的I2C代码示例：

#include "stm32f4xx.h"
#include "stm32f4xx_i2c.h"

#define I2C_TIMEOUT_MAX 0x3000 /* I2C Time out max value */

I2C_HandleTypeDef I2C_Handle;

void I2C_Init(void)
{
    GPIO_InitTypeDef GPIO_InitStructure;

    /* Enable I2C and GPIO clocks */
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

    /* Configure I2C pins */
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_9;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOB, &GPIO_InitStructure);

    /* Assign alternate functions to I2C pins */
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1);
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource9, GPIO_AF_I2C1);

    /* Configure I2C */
    I2C_Handle.Instance = I2C1;
    I2C_Handle.Init.ClockSpeed = 100000;
    I2C_Handle.Init.DutyCycle = I2C_DutyCycle_2;
    I2C_Handle.Init.OwnAddress1 = 0x00;
    I2C_Handle.Init.AddressingMode = I2C_AddressingMode_7bit;
    I2C_Handle.Init.DualAddressMode = I2C_DualAddress_Disable;
    I2C_Handle.Init.OwnAddress2 = 0x00;
    I2C_Handle.Init.GeneralCallMode = I2C_GeneralCall_Disable;
    I2C_Handle.Init.NoStretchMode = I2C_NoStretch_Disable;
    I2C_Init(&I2C_Handle);

    /* Enable I2C */
    I2C_Cmd(I2C_Handle.Instance, ENABLE);
}

uint8_t I2C_Write(I2C_TypeDef* I2Cx, uint8_t addr, uint8_t* data, uint16_t len)
{
    uint32_t timeout = I2C_TIMEOUT_MAX;
    uint8_t status = 0;

    /* Wait until I2C is ready */
    while(I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Send start condition */
    I2C_GenerateSTART(I2Cx, ENABLE);

    /* Wait until start condition is sent */
    while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Send slave address */
    I2C_Send7bitAddress(I2Cx, addr, I2C_Direction_Transmitter);

    /* Wait until slave acknowledges address */
    timeout = I2C_TIMEOUT_MAX;
    while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Send data */
    while(len--)
    {
        I2C_SendData(I2Cx, *data);

        /* Wait until data is sent */
        timeout = I2C_TIMEOUT_MAX;
        while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
        {
            if((timeout--) == 0)
            {
                return 0xFF;
            }
        }

        data++;
    }

    /* Send stop condition */
    I2C_GenerateSTOP(I2Cx, ENABLE);

    return status;
}

uint8_t I2C_Read(I2C_TypeDef* I2Cx, uint8_t addr, uint8_t* data, uint16_t len)
{
    uint32_t timeout = I2C_TIMEOUT_MAX;
    uint8_t status = 0;

    /* Wait until I2C is ready */
    while(I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Send start condition */
    I2C_GenerateSTART(I2Cx, ENABLE);

    /* Wait until start condition is sent */
    while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Send slave address */
    I2C_Send7bitAddress(I2Cx, addr, I2C_Direction_Receiver);

    /* Wait until slave acknowledges address */
    timeout = I2C_TIMEOUT_MAX;
    while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))
    {
        if((timeout--) == 0)
        {
            return 0xFF;
        }
    }

    /* Receive data */
    while(len--)
    {
        /* Wait until data is received */
        timeout = I2C_TIMEOUT_MAX;
        while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED))
        {
            if((timeout--) == 0)
            {
                return 0xFF;
            }
        }

        *data = I2C_ReceiveData(I2Cx);
        data++;
    }

    /* Send stop condition */
    I2C_GenerateSTOP(I2Cx, ENABLE);

    return status;
}

使用示例：

uint8_t data[2];

I2C_Init();

data[0] = 0x01;
data[1] = 0x02;

I2C_Write(I2C1, 0x50, data, 2);

I2C_Read(I2C1, 0x50, data, 2);

以上是一个简单的I2C读写函数示例，可以根据需要进行修改和扩展。