编写一段STM32 I2C驱动代码

这里提供一个简单的STM32 I2C驱动代码，需要根据具体的芯片型号和硬件连接进行修改。

#include "stm32f4xx.h"

#define I2C_TIMEOUT 10000

void I2C_Init() {
    GPIO_InitTypeDef GPIO_InitStruct;
    I2C_InitTypeDef I2C_InitStruct;

    // Enable I2C clock
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);

    // Enable GPIO clock
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE);

    // Configure I2C pins
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_OD;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOB, &GPIO_InitStruct);

    // Connect I2C pins to AF
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource6, GPIO_AF_I2C1);
    GPIO_PinAFConfig(GPIOB, GPIO_PinSource7, GPIO_AF_I2C1);

    // Configure I2C
    I2C_InitStruct.I2C_ClockSpeed = 100000;
    I2C_InitStruct.I2C_Mode = I2C_Mode_I2C;
    I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2;
    I2C_InitStruct.I2C_OwnAddress1 = 0x00;
    I2C_InitStruct.I2C_Ack = I2C_Ack_Enable;
    I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
    I2C_Init(I2C1, &I2C_InitStruct);

    // Enable I2C
    I2C_Cmd(I2C1, ENABLE);
}

uint8_t I2C_ReadByte(uint8_t slave_address, uint8_t reg_address) {
    uint8_t data = 0;

    // Send start condition
    I2C_GenerateSTART(I2C1, ENABLE);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)) {}

    // Send slave address for write
    I2C_Send7bitAddress(I2C1, slave_address, I2C_Direction_Transmitter);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) {}

    // Send register address
    I2C_SendData(I2C1, reg_address);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) {}

    // Send repeated start condition
    I2C_GenerateSTART(I2C1, ENABLE);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)) {}

    // Send slave address for read
    I2C_Send7bitAddress(I2C1, slave_address, I2C_Direction_Receiver);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED)) {}

    // Receive data byte
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED)) {}
    data = I2C_ReceiveData(I2C1);

    // Send stop condition
    I2C_GenerateSTOP(I2C1, ENABLE);

    return data;
}

void I2C_WriteByte(uint8_t slave_address, uint8_t reg_address, uint8_t data) {
    // Send start condition
    I2C_GenerateSTART(I2C1, ENABLE);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT)) {}

    // Send slave address for write
    I2C_Send7bitAddress(I2C1, slave_address, I2C_Direction_Transmitter);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)) {}

    // Send register address
    I2C_SendData(I2C1, reg_address);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) {}

    // Send data byte
    I2C_SendData(I2C1, data);
    while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED)) {}

    // Send stop condition
    I2C_GenerateSTOP(I2C1, ENABLE);
}

这个代码实现了基本的I2C读写操作，使用了STM32的标准库函数。需要注意的是，这个代码只是提供了一个参考，具体的实现还需要根据硬件的具体情况进行调整。