嵌入式系统 C++ 框架之竞争优势解析

#include <zephyr/device.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/logging/log.h>
#include <zephyr/net/mqtt.h>

struct sensor_data {
    int16_t temperature;
    int16_t humidity;
};

struct sensor_thread_param {
    const char *device_name;
    struct sensor_data *data;
};

void *sensor_thread(void *param) {
    const struct sensor_thread_param *arg = (const struct sensor_thread_param *)param;
    struct device *sensor;
    const struct device *dev;
    int ret;

    sensor = device_get_binding(arg->device_name);
    if (!sensor) {
        LOG_ERR("Cannot find device %s", arg->device_name);
        return NULL;
    }
    while (1) {
        k_sleep(K_SECONDS(1));
        ret = sensor_sample_fetch(sensor);
        if (ret < 0) {
            LOG_ERR("Failed to fetch sample from %s: %d", arg->device_name, ret);
            continue;
        }
        struct sensor_data data;
        ret = sensor_channel_get(sensor, SENSOR_CHAN_HUMIDITY, &data.humidity);
        if (ret < 0) {
            LOG_ERR("Failed to get humidity from %s: %d", arg->device_name, ret);
            continue;
        }
        ret = sensor_channel_get(sensor, SENSOR_CHAN_AMBIENT_TEMP, &data.temperature);
        if (ret < 0) {
            LOG_ERR("Failed to get temperature from %s: %d", arg->device_name, ret);
            continue;
        }
        arg->data->temperature = data.temperature;
        arg->data->humidity = data.humidity;
    }
    return NULL;
}

void main(void) {
    struct sensor_data data;
    struct sensor_thread_param params[2] = {
        {"SENSOR_1", &data},
        {"SENSOR_2", &data},
    };
    k_tid_t tid[2];
    char mqtt_client_id[MQTT_ID_SIZE];

    // Set up Zephyr resources
    if (mqtt_client_id_create(mqtt_client_id, sizeof(mqtt_client_id)) < 0) {
        LOG_ERR("Failed to create MQTT client ID");
        return;
    }
    mqtt_connect();
    for (int i = 0; i < ARRAY_SIZE(params); i++) {
        tid[i] = k_thread_spawn(NULL, &params[i], sensor_thread, &params[i], NULL, NULL, K_PRIO_COOP, 0);
        if (!tid[i]) {
            LOG_ERR("Failed to create sensor %d thread", i);
            return;
        }
    }
    while (1) {
        k_sleep(K_SECONDS(1));
        mqtt_publish();
    }
}

#include "mbed.h"
#include "WiFiInterface.h"
#include "MQTTNetwork.h"
#include "MQTTSNClient.h"

WiFiInterface wifi;
MQTTNetwork network(wifi);
MQTTSNClient client(network);

DigitalOut led(LED1);
AnalogIn sensor(A0);

void mqtt_message_callback(MessageData *md) {
    MQTT::Message &message = md->message;
    if (message.payloadlen) {
        if (strcmp(message.payload, "on") == 0) {
            led = 1;
        } else if (strcmp(message.payload, "off") == 0) {
            led = 0;
        }
    }
}

int main() {
    wifi.connect("YOUR_SSID", "YOUR_PASSWORD");
    client.connect(MQTT_SERVER, MQTT_PORT);
    client.subscribe(MQTT_TOPIC);
    client.messageHandler = mqtt_message_callback;
    while (1) {
        float value = sensor.read();
        char buf[16];
        sprintf(buf, "%.2f", value);
        client.publish(MQTT_TOPIC, buf, strlen(buf));
        client.yield(1000);
    }
}