EspressoLite V2 with flow sensor

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EspressoLite V2 with flow sensor

Postby fariqatrash » Mon May 15, 2017 12:46 pm

Hi.

I would like to use EspressoLite V2 with Flow meter (Hall effect) and link them to Blynk server.
The problem:
When I blew the flow meter, the serial monitor did not register any value.
But when I used the flow meter with CT-Uno, i got the reading.

Sketch:
#define BLYNK_PRINT Serial

#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>

// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth="token";

// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "ssid";
char pass[] = "pass";

byte statusLed = 13;
byte sensorInterrupt = 0; // 0 = digital pin 2
byte sensorPin = 14;

// 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;
unsigned int flowMilliLitres;
unsigned long totalMilliLitres;

unsigned long oldTime;

void setup()
{
Serial.begin(9600); //This is the setup function where the serial port is initialised,
Blynk.begin(auth, ssid, pass);
pinMode(statusLed, OUTPUT);
digitalWrite(statusLed, HIGH);

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

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

attachInterrupt(sensorInterrupt, pulseCounter, RISING);

}

void loop()
{
Blynk.run();


// Save the state of Button 0.

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;

unsigned int frac;

// Print the flow rate for this second in litres / minute
Serial.print("Flow rate: ");
Serial.print(int(flowRate)); // Print the integer part of the variable
Serial.print("."); // Print the decimal point
// Determine the fractional part. The 10 multiplier gives us 1 decimal place.
frac = (flowRate - int(flowRate)) * 10;
Serial.print(frac, DEC) ; // Print the fractional part of the variable
Serial.print("L/min");
// Print the number of litres flowed in this second
Serial.print(" Current Liquid Flowing: "); // Output separator
Serial.print(flowMilliLitres);
Serial.print("mL/Sec");

// Print the cumulative total of litres flowed since starting
Serial.print(" Output Liquid Quantity: "); // Output separator
Serial.print(totalMilliLitres);
Serial.println("mL");

// 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);
}

}

void pulseCounter()
{
// Increment the pulse counter
pulseCount++;
}

//This function will be called when the widget in Blynk app
//writes values to the Virtual Pin 0
BLYNK_WRITE(V0)
{
//Gettung the value from pin V0.
int pinValue = param.asInt();

//St the LED state.
digitalWrite(14, !pinValue);


}


please help..
fariqatrash
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Posts: 4
Joined: Mon May 15, 2017 11:53 am

Re: EspressoLite V2 with flow sensor

Postby bengchet » Mon May 15, 2017 2:20 pm

Hi,

It is pin mapping issue. sensorInterrupt should be 2 instead of 0 if you are using ESP8266 pin 2 to connect.

For general case, it is better to put it this way.

Code: Select all
byte sensorInterrupt = 2;  //using pin 2
...
attachInterrupt(digitalPinToInterrupt(sensorInterrupt) , pulseCounter, RISING);


digitalPinToInterrupt solves interrupt pin mapping issue. This can be used for both UNO and ESPresso Lite v2.
bengchet
Moderator
 
Posts: 237
Joined: Tue Aug 25, 2015 8:29 am

Re: EspressoLite V2 with flow sensor

Postby fariqatrash » Mon May 15, 2017 9:15 pm

Thanks Bengchet.

Now serial monitor able to display value .

But I got problem with Blynk.

I tried to get the Gauge widget to work, the I think it cannot read the value from the board.

Code: Select all
  BLYNK_READ(V6)
{
  Blynk.virtualWrite(V6,frac);
}


Is this code okay?
I put the code last..is the location correct?
fariqatrash
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Posts: 4
Joined: Mon May 15, 2017 11:53 am

Re: EspressoLite V2 with flow sensor

Postby fariqatrash » Mon May 15, 2017 9:48 pm

ok..got it..
the value for V6 suppose to be flowRate, not frac..
fariqatrash
Freshie
 
Posts: 4
Joined: Mon May 15, 2017 11:53 am

Re: EspressoLite V2 with flow sensor

Postby bengchet » Tue May 16, 2017 12:54 am

Hi,

Glad to hear that :D
bengchet
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Posts: 237
Joined: Tue Aug 25, 2015 8:29 am


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