sensoresp/include/sensor_bh1750.cpp

//Connect SCL to D1, SDA to D2, GND and 3v3
#include "sensor_bh1750.h"



Sensor_BH1750::Sensor_BH1750()
{
  bh1750 = new BH1750(0x23); //0x23 if addr connected to ground (=pin open), 0x5c if addr pulled high
}

void Sensor_BH1750::init() //Things to be done during setup()
{    
  Serial.println("initializing bh1750");
  Wire.begin();
  if (bh1750->begin(BH1750::CONTINUOUS_HIGH_RES_MODE)) {
    Serial.println(F("BH1750 Advanced begin"));
    init_ok=true;
  } else {
    Serial.println(F("Error initialising BH1750"));
  }
  bh1750->readLightLevel(); //make first reading, could be 0
}

//Also called during setup()
void Sensor_BH1750::setSettings(float minchange, unsigned long senddelaymax, unsigned long readdelay)
{
    data.minchange=minchange;
    data.senddelaymax=senddelaymax;
    data.readdelay=readdelay;
}


//Called during setup
void Sensor_BH1750::advertise(HomieNode& p_sensorNode)
{
    sensorNode = &p_sensorNode;
    sensorNode->advertise("light");
}

void Sensor_BH1750::sensorloop()
{
  if (init_ok) {
    sensordata &d=data;
    
    bool _changed=false;
    if (millis() >= (d.lastreadtime+d.readdelay)) {
      d.value = bh1750->readLightLevel(); // [lux]
      if (fabs(d.lastsentvalue-d.value)>=d.minchange){
        _changed=true;
      }
      d.lastreadtime=millis();
    }

    if (_changed || millis() >= (d.lastsent+d.senddelaymax)) {
      Serial.print("Sending BH1750. reason=");
      if (_changed) Serial.println("change"); else Serial.println("time");

      Homie.getLogger() << "light " << ": " << d.value << endl;
      sensorNode->setProperty("light").send(String(d.value));
      d.lastsentvalue=d.value;
      
      d.lastsent=millis();
    }
  }
}