ESP8266 + MQTT + 土壤湿度传感器

连线

#include
#include
#include
#include


#define PIN_AO A0
#define PIN_DO 4
// wifi info
const char *SSID = "优美屋205"; // 你家的wifi名
const char *PASSWORD = "18111549"; // wifi 密码
// MQTT info https://www.emqx.com/zh/mqtt/public-mqtt5-broker
const char *MQTT_SERVER = "broker-cn.emqx.io"; // MQTT 服务器地址
const int MQTT_PROT = 1883; // MQTT 端口
// mqtt 主题
const char *MQTT_TOPIC_PUB_OnLINE= "my/home/pub_online";
const char *MQTT_TOPIC_PUB_UPDATE = "my/home/pub_update"; // 订阅更新
const char *MQTT_TOPIC_SUB_DATA = "my/home/sub_data"; // 发布
const char *MQTT_TOPIC_HEARTBEAT = "my/home/heartbeat"; // 心跳
const char *CLIENT_ID = "esp8266-457065e5-f063-474e-2saf-cacf5cb52af5";
int M0 = 1024; // 干燥
int M1 = 464; // 最小数 100% 湿度
char *msg;
Ticker ticker;
WiFiClient espClient;
PubSubClient client(espClient);
void init_wifi(); // 初始化wifi
void mqtt_reconnect(); // 重新连接wifi
void mqtt_msg_callback(char *topic, byte *payload, unsigned int length); // mqtt 消息回调
void mqtt_heartbeat(); // 心跳
void update_data(); // 更新数据
void setup()
{
Serial.begin(115200);
init_wifi();
client.setServer(MQTT_SERVER, MQTT_PROT); // 设置mqtt 服务和端口
client.setCallback(mqtt_msg_callback); // 设置mqtt 回调函数
// 心跳
ticker.attach(1, mqtt_heartbeat);
}
void loop()
{
if (!client.connected())
{
mqtt_reconnect();
}
client.loop();
update_data();
}
void init_wifi()
{
Serial.println("Connecting to");
Serial.println(SSID);
WiFi.begin(SSID, PASSWORD);
while (WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(".");
}
}
void mqtt_reconnect()
{
while (!client.connected())
{
Serial.print("Attempting MQTT connection...");
// 第一步: 创建连接
if (client.connect(CLIENT_ID))
{
Serial.println("connected");
client.publish(MQTT_TOPIC_PUB_ONLINE, "online"); // 发布
client.subscribe(MQTT_TOPIC_PUB_UPDATE); // 监听
}
else
{
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
delay(5000);
}
}
}
void mqtt_msg_callback(char *topic, byte *payload, unsigned int length)
{
Serial.print("Message arrived [");
Serial.print(topic); // 打印主题信息
Serial.print("] ");
String data = "";
for (unsigned int i = 0; i {
Serial.print((char)payload[i]); // 打印主题内容
data += (char)payload[i];
}
Serial.println();
}
void mqtt_heartbeat()
{
if (client.connected())
{
client.publish(MQTT_TOPIC_HEARTBEAT, "1");
}
}
void update_data(){
if (client.connected())
{
Serial.print("AO => ");
Serial.print(analogRead(PIN_AO));
Serial.print(" DO =>");
Serial.print(digitalRead(PIN_DO));
float HUMI = (M0 - analogRead(PIN_AO)) / ((M0 - M1) / 100); //将湿度模拟量转换成数字量
Serial.print("HUMI =>");
Serial.print(HUMI);
Serial.println("% ");
if(HUMI <= 30){
msg = "主人，我渴了, 我要喝水";
Serial.println("主人，我渴了, 我要喝水");
}else{
msg = "主人，我不渴";
Serial.println("主人，我不渴");
}
delay(1000);
client.publish(MQTT_TOPIC_SUB_DATA, msg);
}
}