Hi,

Here you can find a simplified version of the WaterFlow node.
This version only sends to the GW the current flow volume in liters/hour.
I don't know your model (G??) as the pulses per liter/hour vary from different flow sensors. Mine is G1" so the math is for this sensor.

I had a problem with interrupts, and this was the way i found to work.

Hope this helps!

#include <SPI.h>
#include <MySensor.h>  

#define DIGITAL_INPUT_SENSOR 3                  // The digital input you attached your sensor.  (Only 2 and 3 generates interrupt!)
#define SENSOR_INTERRUPT DIGITAL_INPUT_SENSOR-2        // Usually the interrupt = pin -2 (on uno/nano anyway)

#define CHILD_ID 1                              // Id of the sensor child

int READ_INTERVAL = 3;           // Read interval to count the pulses (in seconds). 

long lastReadStart;
int flow;

MySensor gw;
MyMessage flowMsg(CHILD_ID,V_FLOW);


int READ_INTERVAL_MILLIS=READ_INTERVAL * 1000;        // Just to simple the math!
volatile unsigned long pulseCount = 0;   

void setup()  
{  
  gw.begin(); 

  // Send the sketch version information to the gateway and Controller
  gw.sendSketchInfo("Water Meter", "1.2");

  // Register this device as Waterflow sensor
  gw.present(CHILD_ID, S_WATER);       

  pulseCount = 0;

  lastReadStart = millis();

  attachInterrupt(SENSOR_INTERRUPT, onPulse, RISING);
}


void loop()     
{ 
  unsigned long currentTime = millis();
	

  if (currentTime - lastReadStart > READ_INTERVAL_MILLIS)
  {
    flow = pulseCount*60/READ_INTERVAL;  //Need to change here for the G type
    lastReadStart=currentTime;
     


      Serial.print("l/hour:");
      Serial.println(flow);
      gw.send(flowMsg.set(flow));
      
      pulseCount = 0;
  }
}


void onPulse()
{
  pulseCount++; 
}```