stm32使用nb-iot连接阿里云

连接阿里云IoT平台需要以下步骤：

1. 注册阿里云账号，并创建一个IoT实例。

2. 在IoT平台的控制台中创建一个设备，并获取设备的三元组信息（即ProductKey、DeviceName和DeviceSecret）。

3. 编写STM32的NB-IoT模组驱动程序，使用AT指令连接移动网络，并通过MQTT协议将数据上传到阿里云IoT平台。

4. 在阿里云IoT平台中创建一个Topic和数据流转规则，将设备上传的数据转发到指定的数据存储、分析或应用系统中。

以下是一个基本的示例程序，供参考：

#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "MQTTClient.h"
#include "stm32f10x.h"
#include "nb_iot.h"

#define PRODUCT_KEY      "XXXXXXXXXXXX"
#define DEVICE_NAME      "XXXXXXXXXXXX"
#define DEVICE_SECRET    "XXXXXXXXXXXX"

#define MQTT_HOST        "XXXXXXXXXXXX.iot-as-mqtt.cn-shanghai.aliyuncs.com"
#define MQTT_PORT        1883
#define MQTT_CLIENT_ID   "iot-client"
#define MQTT_TOPIC       "/sys/"PRODUCT_KEY"/"DEVICE_NAME"/thing/event/property/post"

#define BUFFER_SIZE      256

static char buffer[BUFFER_SIZE];

static void messageArrived(MessageData* data) {
    printf("Message arrived: %.*s\n", data->message->payloadlen, data->message->payload);
}

static int connectToMQTT(void) {
    int rc = 0;
    Network network;
    MQTTClient client;
    MQTTPacket_connectData connectData = MQTTPacket_connectData_initializer;
    
    NewNetwork(&network);
    ConnectNetwork(&network, MQTT_HOST, MQTT_PORT);
    MQTTClientInit(&client, &network, 1000, buffer, BUFFER_SIZE, buffer + BUFFER_SIZE, BUFFER_SIZE);
    
    connectData.clientID.cstring = MQTT_CLIENT_ID;
    connectData.keepAliveInterval = 60;
    connectData.username.cstring = DEVICE_NAME"&"PRODUCT_KEY;
    connectData.password.cstring = DEVICE_SECRET;
    
    rc = MQTTConnect(&client, &connectData);
    if (rc == MQTT_SUCCESS) {
        printf("Connected to MQTT server\n");
        MQTTSubscribe(&client, MQTT_TOPIC, QOS0, messageArrived);
    }
    return rc;
}

static void disconnectFromMQTT(void) {
    NetworkDisconnect(&client->ipstack);
    printf("Disconnected from MQTT server\n");
}

void main(void) {
    nb_iot_init();
    nb_iot_connect("CMNET", NULL, NULL); // 使用CMNET接入移动网络

    if (connectToMQTT() != MQTT_SUCCESS) {
        printf("Failed to connect to MQTT server\n");
        return;
    }

    while (1) {
        // 读取传感器数据
        float temperature = readTemperature();
        float humidity = readHumidity();

        // 发送数据到阿里云IoT平台
        char data[128];
        sprintf(data, "{ \"temperature\": %.2f, \"humidity\": %.2f }", temperature, humidity);
        MQTTMessage message = MQTTMessage_initializer;
        message.payload = data;
        message.payloadlen = strlen(data);
        MQTTPublish(&client, MQTT_TOPIC, &message);
        
        // 等待下一次上传
        delay(5000);
    }

    disconnectFromMQTT();
    nb_iot_disconnect();
}

需要注意的是，以上代码仅用于示例，具体实现需要根据实际情况进行修改和调试。