Raspberry PI - Node-RED - MQTT - Esp8266 - SHT30
L'IOT sempre più semplice - dashboard per la lettura della temperatura e dell'umidità.
Scopo
Creare una dashboard che visualizzi temperatura e umidità rilevati con la scheda SHT30 montata su ESP8266-d1-mini, appoggiandosi su Mosquitto installato sul Raspberry PI, con l'ausilio di Node-RED.
Per l'installazione e il settaggio di Mosquitto e Node-RED si fa riferimento al precedente articolo .
Cosa serve:
- ESp8266 - ESP-01
- Modulo SHT30
- Raspberry PI
- Mosquitto
- Node-RED
Codice sorgente:
/*
mqtt_esp8266_pub_SHT30
Zappoco - mqtt_esp8266_pub_SHT30_20_05_02 10/05/2020 --> modifica e integrazione di SHT30 in Basic ESP8266 MQTT example
questo sketch è ricavato dal Basic ESP8266 MQTT example della libreria PubSubClient
*/
#include "ESP8266WiFi.h"
#include "PubSubClient.h"
#include "WEMOS_SHT3X.h"
SHT3X sht30(0x45);
// Update these with values suitable for your network.
const char* ssid = "MySSID";
const char* password = "MyPassword";
//const char* mqtt_server = "broker.mqtt-dashboard.com";
const char* mqtt_server = "192.168.188.82";
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
char msgTemp[50];
char msgUmid[50];
int value = 0;
void setup_wifi() {
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) {
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
}
Serial.println();
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// Create a random client ID
String clientId = "ESP8266Client-";
clientId += String(random(0xffff), HEX);
// Attempt to connect
if (client.connect(clientId.c_str())) {
Serial.println("connected");
// Once connected, publish an announcement...
// client.publish("outTopic", "hello world");
// ... and resubscribe
client.subscribe("inTopic");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void setup() {
pinMode(BUILTIN_LED, OUTPUT); // Initialize the BUILTIN_LED pin as an output
Serial.begin(115200);
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
long now = millis();
if (now - lastMsg > timeDelay) {
lastMsg = now;
if (sht30.get() == 0) {
//
// coefficienti di taratura sperimentali - in quanto la scheda montata sul mini risente del calore creato dalla stessa
//
//Temperatura = Temperatura * 0.8729 ;
//Umidita = Umidita * 1.1332 ;
Serial.print("Temperature in Celsius : ");
Serial.println(sht30.cTemp * 0.8729);
snprintf (msgTemp, 50, "%4.1f", sht30.cTemp * 0.8729 );
Serial.print("Temperature in Fahrenheit : ");
Serial.println(sht30.fTemp);
Serial.print("Relative Humidity : ");
Serial.println(sht30.humidity * 1.1332 );
snprintf (msgUmid, 50, "%4.1f", sht30.humidity * 1.1332 );
Serial.println();
client.publish("SHT30/temp", msgTemp);
client.publish("SHT30/umid", msgUmid);
}
else
{
Serial.println("Error!");
}
}
}
