Things/things/DeviceDht.h

96 lines
2.7 KiB
C++

#ifndef DEVICEDHT_H
#define DEVICEDHT_H
#include "Device.h"
#include <Homie.h>
#include <DHT.h> // https://github.com/adafruit/DHT-sensor-library
class DeviceDht : public Device {
public:
inline DeviceDht(byte dhtPin, byte dhtType):dht(dhtPin, dhtType) {
pin = dhtPin;
type = dhtType;
}
virtual void setup();
virtual void homieRegister();
virtual void loop();
private:
byte pin;
byte type;
DHT dht;
const int INTERVAL_DHT = 60;
unsigned long lastSentDHT = 0;
float humidity, temperature; // raw values from the sensor
float heatindex; // computed value from the sensor
HomieNode humidityNode{"humidity", "humidity"};
HomieNode temperatureNode{"temperature", "temperature"};
HomieNode heatindexNode{"heatindex", "heatindex"};
};
void DeviceDht::setup() {
pinMode(pin, INPUT);
dht.begin();
}
void DeviceDht::homieRegister() {
Homie.registerNode(humidityNode);
Homie.registerNode(temperatureNode);
Homie.registerNode(heatindexNode);
}
// compare float values
bool isEqual(float a, float b, float epsilon=0.001) {
return fabs(a - b) <= epsilon * fabs(a);
}
void DeviceDht::loop() {
if (millis() - lastSentDHT >= INTERVAL_DHT * 1000UL || lastSentDHT == 0) {
float previousHumidity = humidity;
float previousTemperature = temperature;
float previousHeatindex = heatindex;
humidity = dht.readHumidity(); // read humidity as a percent
temperature = dht.readTemperature(); // read temperature as Celsius
heatindex = dht.computeHeatIndex(temperature, humidity, false);
// check if any reads failed and exit early
if (isnan(humidity) || isnan(temperature)) {
Serial.println("Failed to read from DHT sensor!");
return;
}
if (!isEqual(humidity, previousHumidity)) {
Serial.print("humidity: ");
Serial.println(humidity);
if (!Homie.setNodeProperty(humidityNode, "value", String(humidity), true)) {
Serial.println("Sending failed");
}
} else {
Serial.println("humidity unchanged");
}
if (!isEqual(temperature, previousTemperature)) {
Serial.print("temperature: ");
Serial.println(temperature);
if (!Homie.setNodeProperty(temperatureNode, "value", String(temperature), true)) {
Serial.println("Sending failed");
}
} else {
Serial.println("temperature unchanged");
}
if (!isEqual(heatindex, previousHeatindex)) {
Serial.print("heatindex: ");
Serial.println(heatindex);
if (!Homie.setNodeProperty(heatindexNode, "value", String(heatindex), true)) {
Serial.println("Sending failed");
}
} else {
Serial.println("heatindex unchanged");
}
lastSentDHT = millis();
}
}
#endif