N32G455 M24C02 I2C EEPROM 驱动与页边界处理

#define M24C02_ADDRESS_BYTE ((uint8_t)(M24C02_I2C_ADDRESS << 1U))

typedef enum
{
    M24C02_STATUS_OK = 0,
    M24C02_STATUS_INVALID_PARAM, /* 空指针、长度为 0，或 address + length > 256 */
    M24C02_STATUS_TIMEOUT,       /* 10 ms 内标志未就绪或内部写周期未完成 */
    M24C02_STATUS_NACK,          /* 地址或数据阶段收到 NACK */
    M24C02_STATUS_BUS_ERROR      /* 总线错误、仲裁丢失、溢出等 */
} m24c02_status_t;

m24c02_status_t M24c02_Init(void);
m24c02_status_t M24c02_Read(uint16_t address, uint8_t *data, uint16_t length);
m24c02_status_t M24c02_Write(uint16_t address, const uint8_t *data, uint16_t length);

#include "drv_m24c02.h"

static void Eeprom_Demo(void)
{
    /* 选取跨越 0x0F -> 0x10 页边界的 4 字节测试跨页拆分 */
    uint8_t tx[4] = { 0x10U, 0x32U, 0x54U, 0x76U };
    uint8_t rx[4] = { 0U };

    if (M24c02_Init() != M24C02_STATUS_OK)
    {
        return;
    }

    if (M24c02_Write(0x0EU, tx, sizeof(tx)) != M24C02_STATUS_OK)
    {
        return;
    }

    (void)M24c02_Read(0x0EU, rx, sizeof(rx));
}

#include <string.h>

#define PARAM_SLOT_SIZE (128U)
#define PARAM_MAGIC     (0x5041524DU) /* 'PARM' ASCII 魔数 */

#pragma pack(push, 1)
typedef struct
{
    uint32_t magic;          /* 4B: 魔数标识 */
    uint16_t version;        /* 2B: 参数结构版本号 */
    uint32_t sequence;       /* 4B: 单调递增序号，越大表示版本越新 */
    uint8_t  payload[116];   /* 116B: 业务配置与标定曲线参数 */
    uint16_t crc16;          /* 2B: CRC-16/MODBUS 校验码 (覆盖偏移 0..125) */
} ParamSlot;
#pragma pack(pop)

/* 上电扫描：校验 A/B 两槽，自动选择版本最新且无损的镜像恢复 */
bool ParamStore_Load(ParamSlot *outParams, bool *outActiveIsSlotA)
{
    ParamSlot slotA, slotB;
    bool validA = false;
    bool validB = false;

    if (M24c02_Read(0x00, (uint8_t *)&slotA, sizeof(ParamSlot)) == M24C02_STATUS_OK)
    {
        validA = (slotA.magic == PARAM_MAGIC) &&
                 (slotA.crc16 == Crc16_Modbus((const uint8_t *)&slotA, sizeof(ParamSlot) - 2));
    }

    if (M24c02_Read(0x80, (uint8_t *)&slotB, sizeof(ParamSlot)) == M24C02_STATUS_OK)
    {
        validB = (slotB.magic == PARAM_MAGIC) &&
                 (slotB.crc16 == Crc16_Modbus((const uint8_t *)&slotB, sizeof(ParamSlot) - 2));
    }

    if (validA && validB)
    {
        /* 两个槽位均完整有效，选用序号较大（较新）的槽 */
        if (slotA.sequence >= slotB.sequence)
        {
            *outParams = slotA;
            if (outActiveIsSlotA) *outActiveIsSlotA = true;
        }
        else
        {
            *outParams = slotB;
            if (outActiveIsSlotA) *outActiveIsSlotA = false;
        }
        return true;
    }
    else if (validA)
    {
        *outParams = slotA;
        if (outActiveIsSlotA) *outActiveIsSlotA = true;
        return true;
    }
    else if (validB)
    {
        *outParams = slotB;
        if (outActiveIsSlotA) *outActiveIsSlotA = false;
        return true;
    }

    return false; /* 两槽均损坏（初次上电或硬件故障），应写入出厂默认值 */
}

/* 掉电安全写入：始终写入非活动槽，并整槽读回校验 */
bool ParamStore_Save(const ParamSlot *inParams, bool currentIsSlotA)
{
    uint16_t targetAddr = currentIsSlotA ? 0x80 : 0x00; /* 写入交替备用槽 */
    ParamSlot newSlot = *inParams;
    newSlot.magic = PARAM_MAGIC;
    newSlot.sequence++;
    newSlot.crc16 = Crc16_Modbus((const uint8_t *)&newSlot, sizeof(ParamSlot) - 2);

    /* 1. 跨 8 页写入目标槽 */
    if (M24c02_Write(targetAddr, (const uint8_t *)&newSlot, sizeof(ParamSlot)) != M24C02_STATUS_OK)
    {
        return false;
    }

    /* 2. 写后整槽读回逐字节校验，确保物理无损 */
    ParamSlot readback;
    if (M24c02_Read(targetAddr, (uint8_t *)&readback, sizeof(ParamSlot)) != M24C02_STATUS_OK)
    {
        return false;
    }

    return (memcmp(&newSlot, &readback, sizeof(ParamSlot)) == 0);
}