EEPROM驱动开发笔记（M24C32）

#define NUM 32

    {
        uint8_t data[NUM];
        for (uint8_t i = 0; i < NUM; i++) {
            data[i] = i + 1;
        }
        E2WriteMulti(0x0001, data, NUM);  // 连续写入，从地址0x0001写入32个字节，
        DelayXms(20);
    }

    // 这里使用M23C32了，并回读0x0000和0x0001上的内容
    // 0x0000 32
    // 0x0001 01
    // 符合预期，这里第32个字节已经超出当前页大小，内容会写入该页的页首

/**
 * @brief   把多个字节数据连续写入EEPROM，遇页边界自动分多次写入
 * @param   u16Addr 待写入数据存储起始地址
 * @param   u8Dat   待写入数据指针
 * @param   u16Len  写入数据长度
 * @retval  自动处理页边界，避免跨页写入导致数据覆盖
 */
static void WriteMultiDataToI2C(uint16_t u16Addr, const uint8_t *u8Dat, uint16_t u16Len)
{
    const uint16_t u16PageSize = 32; // 以M24C32为例，页大小为32字节
    uint16_t u16Remain = u16Len;     // 剩余待写字节数
    uint16_t u16CurAddr = u16Addr;   // 当前写入地址
    const uint8_t *pu8Cur = u8Dat;   // 当前写入数据指针

    while (u16Remain > 0)
    {
        // 等待写入间隔，防止EEPROM写入过快
        while (g_uE2Interval < E2_INTERVAL_CONST)
        {
            WDT_Restart();
        }

        // 计算本次写入不跨页的最大字节数
        uint16_t u16PageOffset = u16CurAddr % u16PageSize;
        uint16_t u16BytesThisPage = u16PageSize - u16PageOffset;
        if (u16BytesThisPage > u16Remain)
            u16BytesThisPage = u16Remain;

        // 开始页写操作
        EEPROM_WP_DISABLE;
        I2CStart();
        I2CSendByte(0xa0); // 设备地址
        WaitAck();
        I2CSendByte(u16CurAddr >> 8); // 高8位地址
        WaitAck();
        I2CSendByte(u16CurAddr & 0xff); // 低8位地址
        WaitAck();
        for (uint16_t i = 0; i < u16BytesThisPage; i++)
        {
            I2CSendByte(pu8Cur[i]); // 发送数据
            WaitAck();
        }
        I2CStop();
        EEPROM_WP_ENABLE;
        g_uE2Interval = 0; // 重置写入间隔计数

        // 更新指针和计数，准备下次写入
        u16CurAddr += u16BytesThisPage;
        pu8Cur += u16BytesThisPage;
        u16Remain -= u16BytesThisPage;
    }
}

static void BspM24c32I2cStart(void)
{
    BSP_I2C_SCL_HIGH;
    BSP_I2C_SDA_HIGH;
    BSP_I2C_WAIT;

    BSP_I2C_SDA_LOW;
    BSP_I2C_WAIT;

    BSP_I2C_SCL_LOW;
    BSP_I2C_WAIT;
}

// 起始信号时序：
// SCL:  ‾‾‾‾‾‾‾‾‾\_____
// SDA:  ‾‾‾‾‾‾‾‾\______
//               ↑ 在SCL高时SDA下降沿

static void BspM24c32I2cSendAck(void)
{
    BSP_I2C_SDA_LOW;
    BSP_I2C_WAIT;
    BSP_I2C_SCL_HIGH;
    BSP_I2C_WAIT;

    BSP_I2C_SCL_LOW;
    BSP_I2C_WAIT;
}

// ACK信号时序：
// SCL:  _____/‾‾‾‾\_____
// SDA:  _____↓__________
//            第9时钟（先设置低电平）

#define BSP_WP_ENABLE                    Gpio_SetIO(BSP_AT24C16C_EEPROM_WP_PORT, BSP_AT24C16C_EEPROM_WP_PIN)  // 写保护使能，WP高电平
#define BSP_WP_DISABLE                   Gpio_ClrIO(BSP_AT24C16C_EEPROM_WP_PORT, BSP_AT24C16C_EEPROM_WP_PIN)  // 取消写保护，WP低电平

/**
 * @brief 发送EEPROM地址
 * @param u16Addr 要访问的地址
 * @return 发送结果
 */
static int32_t EepromSendAddress(uint16_t u16Addr)
{
    int32_t s32Ret;

    // 检查地址范围
    if (u16Addr >= AT24C16C_EEPROM_TOTAL_SIZE) {
        return CMN_ERROR_EEPROM_ADDR_ERR;
    }

    // AT24C16C地址格式：11位地址，高3位作为页选择
    uint8_t u8AddrHigh = (u16Addr >> 8) & 0x07;  // 高3位
    uint8_t u8AddrLow = u16Addr & 0xFF;          // 低8位

    // 设备地址（写模式）包含页选择位
    uint8_t u8DevAddr = AT24C16C_EEPROM_DEVICE_ADDR | (u8AddrHigh << 1);

    // 发送起始信号
    I2C_SetFunc(BSP_EEPROM_I2C, I2cStart_En);

    s32Ret = EepromCheckWriteAck();  // 检查起始条件状态
    if (s32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        return s32Ret;
    }

    // 发送设备地址
    s32Ret = I2C_WriteByte(BSP_EEPROM_I2C, u8DevAddr);
    I2C_ClearIrq(BSP_EEPROM_I2C);
    if (s32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        return CMN_ERROR_EEPROM_WRITE_ERR;
    }

    s32Ret = EepromCheckWriteAck();  // 检查设备地址ACK状态
    if (s32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        return s32Ret;
    }

    // 发送地址低字节
    s32Ret = I2C_WriteByte(BSP_EEPROM_I2C, u8AddrLow);
    I2C_ClearIrq(BSP_EEPROM_I2C);
    if (s32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        return CMN_ERROR_EEPROM_WRITE_ERR;
    }

    s32Ret = EepromCheckWriteAck();  // 检查地址低字节ACK状态
    if (s32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        return s32Ret;
    }

    return CMN_SUCCESS;
}

/**
 * @brief 写入单个字节
 * @param u16Addr 写入地址
 * @param u8Data 写入数据
 * @return 写入结果
 */
int32_t BspAt24c16cEepromWriteByte(uint16_t u16Addr, uint8_t u8Data)
{
    int32_t i32Ret;

    if (!s_bEepromInitialized) {
        return CMN_ERROR_EEPROM_INIT_ERR;
    }

    // 检查地址范围
    if (u16Addr >= AT24C16C_EEPROM_TOTAL_SIZE) {
        return CMN_ERROR_EEPROM_ADDR_ERR;
    }

    BSP_WP_DISABLE;

    // 发送地址
    i32Ret = EepromSendAddress(u16Addr);
    if (i32Ret != CMN_SUCCESS) {
        BSP_WP_ENABLE;
        return i32Ret;
    }

    // 写入数据
    i32Ret = I2C_WriteByte(BSP_EEPROM_I2C, u8Data);
    I2C_ClearIrq(BSP_EEPROM_I2C);
    if (i32Ret != Ok) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return CMN_ERROR_EEPROM_WRITE_ERR;
    }

    i32Ret = EepromCheckWriteAck();
    if (i32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return i32Ret;
    }

    // 发送停止信号
    I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
    I2C_ClearIrq(BSP_EEPROM_I2C);

    BSP_WP_ENABLE;

    return CMN_SUCCESS;
}

/**
 * @brief 读取单个字节
 * @param u16Addr 读取地址
 * @param pu8Data 读取数据指针
 * @return 读取结果
 */
int32_t BspAt24c16cEepromReadByte(uint16_t u16Addr, uint8_t *pu8Data)
{
    int32_t i32Ret;

    if (!s_bEepromInitialized) {
        return CMN_ERROR_EEPROM_INIT_ERR;
    }

    if (pu8Data == NULL) {
        return CMN_ERROR_EEPROM_READ_ERR;
    }

    // 检查地址范围
    if (u16Addr >= AT24C16C_EEPROM_TOTAL_SIZE) {
        return CMN_ERROR_EEPROM_ADDR_ERR;
    }

    BSP_WP_DISABLE;

    // 发送地址（写模式）
    i32Ret = EepromSendAddress(u16Addr);
    if (i32Ret != CMN_SUCCESS) {
        BSP_WP_ENABLE;
        return i32Ret;
    }

    // 重新开始信号，切换到读模式
    I2C_SetFunc(BSP_EEPROM_I2C, I2cStart_En);
    I2C_ClearIrq(BSP_EEPROM_I2C);

    i32Ret = EepromCheckReadAck();  // 检查重新开始的起始条件状态
    if (i32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return i32Ret;
    }

    // 发送地址（读模式）
    i32Ret = I2C_WriteByte(BSP_EEPROM_I2C, AT24C16C_EEPROM_DEVICE_ADDR | 0x01);
    I2C_ClearIrq(BSP_EEPROM_I2C);
    if (i32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return CMN_ERROR_EEPROM_READ_ERR;
    }

    i32Ret = EepromCheckReadAck();  // 检查设备地址ACK状态
    if (i32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return i32Ret;
    }

    I2C_ClearFunc(BSP_EEPROM_I2C, I2cAck_En);
    I2C_ClearIrq(BSP_EEPROM_I2C);

    i32Ret = EepromCheckReadAck();  // 0x58 已接收到最后一个数据，NACK已返回
    if (i32Ret != CMN_SUCCESS) {
        I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
        I2C_ClearIrq(BSP_EEPROM_I2C);
        BSP_WP_ENABLE;
        return i32Ret;
    }

    // 准备读取最后一个字节（发送NACK）
    *pu8Data = I2C_ReadByte(BSP_EEPROM_I2C);
    LOG_DEBUG("pu8Data %d", *pu8Data);

    // 发送停止信号
    I2C_SetFunc(BSP_EEPROM_I2C, I2cStop_En);
    I2C_ClearIrq(BSP_EEPROM_I2C);

    // 恢复ACK使能
    I2C_SetFunc(BSP_EEPROM_I2C, I2cAck_En);

    BSP_WP_ENABLE;

    return CMN_SUCCESS;
}