W55MH32使用MQTT协议连接OneNET

本篇总结

本例程在 W55MH32 上通过 MQTT 协议接入中移物联网 OneNET 平台，实现温湿度数据上报与 LED 主题的订阅控制。

硬件平台：本例程基于 W55MH32L-EVB 开发板运行。

采购推荐：点击前往 WIZnet 官方淘宝店铺 选购 W55MH32L-EVB

OneNET 平台简介

OneNET 是中移物联网有限公司打造的 PaaS 物联网平台，支持 MQTT、HTTP、LwM2M 等多种协议接入。本例程使用 OneNET MQTT 接入方式（mqtts.heclouds.com:1883），采用 token 鉴权（HMAC-SHA1 加密）。设备通过发布数据点上报遥测数据，通过订阅命令主题接收云端控制指令。

void TIM3_IRQHandler(void)
{
    static uint32_t tim3_1ms_count = 0;
    if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET)
    {
        tim3_1ms_count++;
        MilliTimer_Handler();

        if (tim3_1ms_count >= 1000)
        {
            DHCP_time_handler();
            DNS_time_handler();
            tim3_1ms_count = 0;
        }

        TIM_ClearITPendingBit(TIM3, TIM_IT_Update);
    }
}

mqttconn mqtt_params = {
    .mqttHostUrl    = "mqtts.heclouds.com",
    .server_ip      = {0},
    .port           = 1883,
    .clientid       = "W5100S_W5500",
    .username       = "70TwP2gxl5",
    .passwd         = "version=2018-10-31&res=products%2F70TwP2gxl5%2Fdevices%2FW5100S_W5500&et=1791400694&method=sha1&sign=0SchVg6Y2MRYn%2B9zItNZwt%2F%2FN4Y%3D",
    .pubtopic       = "$sys/70TwP2gxl5/W5100S_W5500/thing/property/post",
    .pubtopic_reply = "$sys/70TwP2gxl5/W5100S_W5500/thing/property/post/reply",
    .subtopic       = "$sys/70TwP2gxl5/W5100S_W5500/thing/property/set",
    .subtopic_reply = "$sys/70TwP2gxl5/W5100S_W5500/thing/property/set_reply",
    .pubQoS         = QOS0,
    .willtopic      = "/wizchip/will",
    .willQoS        = QOS0,
    .willmsg        = "wizchip offline!",
    .subQoS         = QOS0,
};

如果你想自定义

• clientid/username → 填写设备的 device_id（设备 ID）
• passwd → OneNET token，格式为 version&res&et&method&sign，sign 由 access_key 通过 HMAC-SHA1 生成
• pubtopic / subtopic → OneNET 物模型的主题，格式为 $sys/{pid}/{device_id}/thing/property/...
• willtopic / willmsg → 遗嘱主题和消息，设备异常掉线时由 Broker 代发

void mqtt_init(uint8_t sn, uint8_t *send_buf, uint8_t *recv_buf)
{
    wiz_NetInfo get_info = {0};
    wizchip_getnetinfo(&get_info);

    /* DNS 解析 OneNET 服务器域名 */
    if (do_dns(send_buf, (uint8_t *)mqtt_params.mqttHostUrl, mqtt_params.server_ip))
    {
        while (1);
    }

    NewNetwork(&n, sn);
    ConnectNetwork(&n, mqtt_params.server_ip, mqtt_params.port);
    MQTTClientInit(&c, &n, 1000, send_buf, MQTT_ETHERNET_MAX_SIZE, recv_buf, MQTT_ETHERNET_MAX_SIZE);

    /* 遗嘱参数配置 */
    data.willFlag = 0;
    willdata.qos = mqtt_params.willQoS;
    willdata.topicName.lenstring.data = mqtt_params.willtopic;
    willdata.topicName.lenstring.len  = strlen(willdata.topicName.lenstring.data);
    willdata.message.lenstring.data   = mqtt_params.willmsg;
    willdata.message.lenstring.len    = strlen(willdata.message.lenstring.data);
    willdata.retained      = 0;
    willdata.struct_version = 3;
    data.will              = willdata;

    /* MQTT 连接参数 */
    data.MQTTVersion       = 4;
    data.clientID.cstring  = mqtt_params.clientid;
    data.username.cstring  = mqtt_params.username;
    data.password.cstring  = mqtt_params.passwd;
    data.keepAliveInterval = 30;
    data.cleansession      = 1;
}

void do_mqtt(void)
{
    uint8_t ret;
    switch (run_status)
    {
    case CONN: {
        ret = MQTTConnect(&c, &data);
        printf("Connect to the MQTT server: %d.%d.%d.%d:%d\r\n",
               mqtt_params.server_ip[0], mqtt_params.server_ip[1],
               mqtt_params.server_ip[2], mqtt_params.server_ip[3],
               mqtt_params.port);
        printf("Connected:%s\r\n\r\n", ret == SUCCESSS ? "success" : "failed");
        if (ret != SUCCESSS) run_status = ERR;
        else                 run_status = SUB;
        break;
    }

    case SUB: {
        /* 订阅属性设置主题 */
        ret = MQTTSubscribe(&c, mqtt_params.subtopic, mqtt_params.subQoS, messageArrived);
        printf("Subscribing to %s\r\n", mqtt_params.subtopic);
        printf("Subscribed:%s\r\n\r\n", ret == SUCCESSS ? "success" : "failed");
        if (ret != SUCCESSS) { run_status = ERR; break; }

        /* 订阅属性上报回复主题 */
        ret = MQTTSubscribe(&c, mqtt_params.pubtopic_reply, mqtt_params.subQoS, messageArrived);
        printf("Subscribing to %s\r\n", mqtt_params.pubtopic_reply);
        printf("Subscribed:%s\r\n\r\n", ret == SUCCESSS ? "success" : "failed");
        if (ret != SUCCESSS) run_status = ERR;
        else                 run_status = PUB_MESSAGE;
        break;
    }

    case PUB_MESSAGE: {
        pubmessage.qos = QOS0;
        pubmessage.payload = "{\"id\":\"123\",\"version\":\"1.0\",\"params\":{\"CurrentTemperature\":{\"value\":26.6}}}";
        pubmessage.payloadlen = strlen(pubmessage.payload);
        ret = MQTTPublish(&c, (char *)&(mqtt_params.pubtopic), &pubmessage);
        if (ret != SUCCESSS) { run_status = ERR; }
        else {
            printf("publish:%s,%s\r\n\r\n", mqtt_params.pubtopic, (char *)pubmessage.payload);
            run_status = KEEPALIVE;
        }
        break;
    }

    case KEEPALIVE: {
        if (MQTTYield(&c, 30) != SUCCESSS) run_status = ERR;
        delay_ms(100);
    }
    /* no break — 继续执行 RECV */

    case RECV: {
        if (mqtt_recv_flag) {
            mqtt_recv_flag = 0;
            json_decode(mqtt_recv_msg);
        }
        delay_ms(100);
        break;
    }

    case ERR:
        printf("system ERROR!");
        delay_ms(1000);
        break;

    default:
        break;
    }
}

void messageArrived(MessageData *md)
{
    char topicname[64] = {0};
    char msg[512] = {0};

    sprintf(topicname, "%.*s", (int)md->topicName->lenstring.len, md->topicName->lenstring.data);
    sprintf(msg, "%.*s", (int)md->message->payloadlen, (char *)md->message->payload);
    printf("recv:%s,%s\r\n\r\n", topicname, msg);

    /* 只处理 set 主题的消息，post/reply 主题仅打印 */
    if (strcmp(topicname, mqtt_params.subtopic) == 0)
    {
        mqtt_recv_flag = 1;
        memset(mqtt_recv_msg, 0, sizeof(mqtt_recv_msg));
        memcpy(mqtt_recv_msg, msg, strlen(msg));
    }
}

void json_decode(char *msg)
{
    int ret;
    char replymsg[128] = {0};
    cJSON *id       = NULL;
    cJSON *jsondata = NULL;
    cJSON *params   = NULL;
    cJSON *LED      = NULL;

    jsondata = cJSON_Parse(msg);
    if (jsondata == NULL) { printf("json parse fail.\r\n"); return; }

    id     = cJSON_GetObjectItem(jsondata, "id");
    params = cJSON_GetObjectItem(jsondata, "params");
    LED    = cJSON_GetObjectItem(params, "LEDSwitch");

    if (LED->valueint) printf("LED ON\r\n");
    else               printf("LED OFF\r\n");

    /* 构造并发布响应 */
    sprintf(replymsg, "{\"id\":\"%s\",\"code\":200,\"msg\":\"success\"}", id->valuestring);
    printf("reply:%s\r\n", replymsg);

    pubmessage.qos        = QOS0;
    pubmessage.payload    = replymsg;
    pubmessage.payloadlen = strlen(replymsg);
    ret = MQTTPublish(&c, mqtt_params.subtopic_reply, &pubmessage);
    if (ret != SUCCESSS) run_status = ERR;
    else printf("publish:%s,%s\r\n\r\n", mqtt_params.subtopic_reply, (char *)pubmessage.payload);

    cJSON_Delete(jsondata);
}

JSON 解析说明

json_decode() 使用 cJSON 库解析OneNET 下发的指令格式为 {"id":"xxx","version":"1.0","params":{"LEDSwitch":1}}。解析后除了打印 LED 状态，还会自动构造响应 {"id":"xxx","code":200,"msg":"success"} 并通过 subtopic_reply 主题回发给 OneNET 平台，确认指令已成功处理。