[SOLVED] Flow meter intergration with Wemos D1

Hi all, I have the following code that works fine tested on my Arduino Uno with the YF-S201 Flow Sensor, but the basic code will not function on a Wemos. Can anyone tell me what changes I have to make to get this to work.
Once that is done integrating it into a Blynk application should be easy enough.

byte sensorInterrupt = 0;  // 0 = digital pin 2
byte sensorPin       = 4;

// The hall-effect flow sensor outputs approximately 4.5 pulses per second per
// litre/minute of flow.
float calibrationFactor = 4.5;

volatile byte pulseCount;  

float flowRate;
int flowMilliLitres;
float totalMilliLitres;
float totalpour;
unsigned long oldTime; 

void setup()
{
  
  // Initialize a serial connection for reporting values to the host
  Serial.begin(38400);
   

  
  
  pinMode(sensorPin, INPUT);
  digitalWrite(sensorPin, HIGH);

  pulseCount        = 0;
  flowRate          = 0.0;
  flowMilliLitres   = 0;
  totalMilliLitres  = 0;
  oldTime           = 0;

  // The Hall-effect sensor is connected to pin 2 which uses interrupt 0.
  // Configured to trigger on a FALLING state change (transition from HIGH
  // state to LOW state)
  attachInterrupt(sensorInterrupt, pulseCounter, FALLING);
}


void loop()
{
   
   if((millis() - oldTime) > 1000)    // Only process counters once per second
  { 
    // Disable the interrupt while calculating flow rate and sending the value to
    // the host
    detachInterrupt(sensorInterrupt);
        
    // Because this loop may not complete in exactly 1 second intervals we calculate
    // the number of milliseconds that have passed since the last execution and use
    // that to scale the output. We also apply the calibrationFactor to scale the output
    // based on the number of pulses per second per units of measure (litres/minute in
    // this case) coming from the sensor.
    flowRate = ((1000.0 / (millis() - oldTime)) * pulseCount) / calibrationFactor;
    
    // Note the time this processing pass was executed. Note that because we've
    // disabled interrupts the millis() function won't actually be incrementing right
    // at this point, but it will still return the value it was set to just before
    // interrupts went away.
    oldTime = millis();
    
    // Divide the flow rate in litres/minute by 60 to determine how many litres have
    // passed through the sensor in this 1 second interval, then multiply by 1000 to
    // convert to millilitres.
    flowMilliLitres = (flowRate / 60) * 1000;
    
    // Add the millilitres passed in this second to the cumulative total
    totalMilliLitres += flowMilliLitres;
      
    totalpour =(20 - (totalMilliLitres / 1000));
    
  

    // Print the cumulative total of litres flowed since starting
 
    Serial.print(" Keg Remaining: ");
    Serial.print(totalpour, 2);
    Serial.println(" Litres ");
    // Reset the pulse counter so we can start incrementing again
    pulseCount = 0;
    
    // Enable the interrupt again now that we've finished sending output
    attachInterrupt(sensorInterrupt, pulseCounter, FALLING);
  }
}

/*
Insterrupt Service Routine
 */
void pulseCounter()
{
  // Increment the pulse counter
  pulseCount++;
}
1 Like

Not really a BLYNK related question, but I will give it a go anyways.

Check your pin assignments. You may want to confirm that 0 = digital pin 2 as you have stated in you code.

On a WEMOS (D1 mini), I think D0 is GPIO16, and GPIO0 is D3.

https://www.wemos.cc/product/d1-mini-pro.html

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@Toro_Blanco already said it best… this is not Blynk related and this forum is not a code factory.

Even if it was Blynk specific, you would need to give out more details than you have

Doesn’t what??.. compile, doesn’t load, will not run, runs with errors, runs with faulty data, runs but tries to take over the world… etc… details please :wink:

@Toro_Blanco Thank you for taking the time to help, that was exactly what I needed to know.
Now I have the project running in Blynk on my Wemos.
Thank you again! wish there were more like you!

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@plotto there’s a Blynk controlled flow meter with an ESP up on Instructables now at http://www.instructables.com/id/WATER-SUPPLY-ALERT-MONITORING-SYSTEM-Blynk/

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