I have a kegerator that I am trying to make smarter. I want to track the ounces that are poured, do a few simple math equations and determine how many ounces I just pored in my glass and how many ounces are left in the keg.
It seems like this will require power at all times to hold the values, not an issue. I already have a working sketch with the flow sensor. It will show total volume poured right now.
My learning style is to find an example of what I want then modify it to fit my application with a lot of help file browsing so I understand what I am actually using.
Am I asking too much from my little uno? Below is my code
/*
Liquid flow rate sensor -DIYhacking.com Arvind Sanjeev
Measure the liquid/water flow rate using this code.
Connect Vcc and Gnd of sensor to arduino, and the
signal line to arduino digital pin 2.
*/
byte statusLed = 13;
byte sensorInterrupt = 0; // 0 = digital pin 2
byte sensorPin = 2;
// The hall-effect flow sensor outputs approximately 4.5 pulses per second per
// litre/minute of flow.
float calibrationFactor = 18.7;
volatile byte pulseCount;
float flowRate;
unsigned int flowMilliLitres;
unsigned long totalMilliLitres;
float kegOZ = 661;
float ozPOURED = 24.07;
float BeerLeft=647.9;
float ounces = 0.0;
unsigned long oldTotalML;
unsigned long oldTime;
void setup()
{
// Initialize a serial connection for reporting values to the host
Serial.begin(9600);
// Set up the status LED line as an output
pinMode(statusLed, OUTPUT);
digitalWrite(statusLed, HIGH); // We have an active-low LED attached
pinMode(sensorPin, INPUT);
digitalWrite(sensorPin, HIGH);
pulseCount = 0;
flowRate = 0.0;
flowMilliLitres = 0;
totalMilliLitres = 0;
oldTime = 0;
oldTotalML =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);
}
/**
* Main program loop
*/
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;
unsigned int frac;
ounces=totalMilliLitres/29.57353;
// 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("L/min");
Serial.print("\t"); // Print tab space
// Print the cumulative total of litres flowed since starting
Serial.print("Output Liquid Quantity: ");
Serial.print(totalMilliLitres);
Serial.println("mL");
Serial.print("\t"); // Print tab space
Serial.print(totalMilliLitres/1000);
Serial.print("L");
// Print the cumulative total of ounces flowed since starting
Serial.print("Output ounces: ");
Serial.print(ounces);
Serial.println("OZ");
Serial.print("\t"); // Print tab space
Serial.print(totalMilliLitres/1000);
Serial.print("L");
if (totalMilliLitres>oldTotalML) {
oldTotalML=(totalMilliLitres);
ozPOURED=(ounces+ozPOURED);
BeerLeft=(ozPOURED-kegOZ);
Serial.print(BeerLeft);
Serial.print(" OUNCES");
ounces=0;
}
// 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++;
}
