Using 5 buttons to make a thermostat for water dispenser, it doesn't work and ends up with bugs

[hatdogernshehe]

I'm using an Arduino Mega 2560 and whenever I press the button to set the hot temperature, it doesn't work and the lcd first the default like display temperature and target threshold then the lcd prints setting hot threshold then threshold set then setting cold threshold then threshold set and it loops, then when i press the up or down button both of the temperature thresholds adds or subtracts the values, it is my first time using buttons for temperature control, usually i only use a potentiometer but this time i want to explore the use of buttons and in the future maybe i'll be connecting this to blynk software.

#include <OneWire.h>
#include <DallasTemperature.h>
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

#define ONE_WIRE_BUS 2 // DATA WIRE FOR TEMP SENSOR
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

// Assigning Pins for Arduino
// Button Pins
const int hot = 44;
const int cold = 46;
const int up = 50;
const int down = 48;
const int set = 52;

// Ultrasonic Sensor Pins
// Water Level Sensor
const int levelSenseTrig = 3;
const int levelSenseEcho = 4;
// Hot Valve Sensor
const int hotDispTrig = 5;
const int hotDispEcho = 6;
// Cold Water Valve Sensor
const int coldDispTrig = 7;
const int coldDispEcho = 8;

// Relay Pins
const int hotValve = 31;     // Solenoid Valve for Hot Water
const int coldValve = 33;    // Solenoid Valve for Cold Water
const int pump = 35;         // Water Pump
const int heater = 37;       // Heating Coil
const int compressor = 39;   // Compressor

// Variables
float hotThreshold = 35;
float coldThreshold = 10;
int hotIncrement = 5;
int coldIncrement = 1;

// Distances Values in centimeter
int waterLevelMinimum = 10;
int waterLevelMaximum = 15;
int tripValve = 5;

// Values
bool setHotThreshold = false;
bool setColdThreshold = false;

// Addresses of 2 DS18B20s
uint8_t sensor1[8] = {0x28, 0x02, 0xE3, 0x79, 0x97, 0x00, 0x03, 0x6F};  // for Cold Sensor
uint8_t sensor2[8] = {0x28, 0x6E, 0x04, 0x94, 0x97, 0x0A, 0x03, 0x69};  // for Hot Sensor

void setup()
{
  Serial.begin(9600);

  // Initialize LCD
  lcd.begin(16, 2);
  lcd.clear();
  lcd.backlight();

  // Relay Pins
  pinMode(hotValve, OUTPUT);
  pinMode(coldValve, OUTPUT);
  pinMode(pump, OUTPUT);
  pinMode(heater, OUTPUT);
  pinMode(compressor, OUTPUT);

  // Button Pins
  pinMode(hot, INPUT_PULLUP);
  pinMode(cold, INPUT_PULLUP);
  pinMode(up, INPUT_PULLUP);
  pinMode(down, INPUT_PULLUP);
  pinMode(set, INPUT_PULLUP);

  // Ultrasonic Sensor
  pinMode(levelSenseTrig, OUTPUT);
  pinMode(levelSenseEcho, INPUT);
  pinMode(hotDispTrig, OUTPUT);
  pinMode(hotDispEcho, INPUT);
  pinMode(coldDispTrig, OUTPUT);
  pinMode(coldDispEcho, INPUT);

  sensors.begin();
}

void loop()
{
  sensors.requestTemperatures();
  float hotThermo = sensors.getTempCByIndex(0);
  float coldThermo = sensors.getTempCByIndex(1);
  updateLCD(hotThermo, coldThermo);
  updateRelays(hotThermo, coldThermo);
  adjustThresholds();
  delay(500);
}

// Display LCD
void updateLCD(float coldThermo, float hotThermo)
{
  lcd.setCursor(0, 0);
  lcd.print("H:");
  lcd.print(hotThermo);
  lcd.print((char)223);
  lcd.print("C T:");
  lcd.print(hotThreshold);
  lcd.print((char)223);
  lcd.print("C");
  
  lcd.setCursor(0, 1);
  lcd.print("C:");
  lcd.print(coldThermo);
  lcd.print((char)223);
  lcd.print("C T:");
  lcd.print(coldThreshold);
  lcd.print((char)223);
  lcd.print("C");
}
// Relay Control
void updateRelays(float coldThermo, float hotThermo)
{
  // Heater
  if (hotThermo >= hotThreshold)
  {
    digitalWrite(heater, HIGH);
  }
  else
  {
    digitalWrite(heater, LOW);
  }

  // Compressor
  if (coldThermo <= coldThreshold)
  {
    digitalWrite(compressor, HIGH);
  }
  else
  {
    digitalWrite(compressor, LOW);
  }

  // Water Pump
  if (getUltrasonicDistance(levelSenseTrig, levelSenseEcho) >= waterLevelMaximum)
  {
    digitalWrite(pump, HIGH);
  }
  else if (getUltrasonicDistance(levelSenseTrig, levelSenseEcho) <= waterLevelMinimum)
  {
    digitalWrite(pump, LOW);
  }

  // Solenoid Valve for Hot Water
  if (getUltrasonicDistance(hotDispTrig, hotDispEcho) <= tripValve)
  {
    digitalWrite(hotValve, HIGH);
  }
  else
  {
    digitalWrite(hotValve, LOW);
  }

  // Solenoid Valve for Cold Water
  if (getUltrasonicDistance(coldDispTrig, coldDispEcho) <= tripValve)
  {
    digitalWrite(coldValve, HIGH);
  }
  else
  {
    digitalWrite(coldValve, LOW);
  }
}

// Adjust Thresholds
void adjustThresholds()
{
  if (digitalRead(hot) == HIGH)
  {
    setHotThreshold = true;
    setColdThreshold = false;
    lcd.clear();
    lcd.print("Setting Hot Threshold");
    delay(1000);
    lcd.clear();
    
    do {
      if (digitalRead(up) == HIGH)
      {
        hotThreshold += hotIncrement;
        delay(200);
      }
    
      if (digitalRead(down) == HIGH)
      {
        hotThreshold -= hotIncrement;
        delay(200);
      }
    } while (digitalRead(set) == LOW);
    
    setHotThreshold = false;
    lcd.clear();
    lcd.print("Threshold Set");
    delay(1000);
    lcd.clear();
  }
  
  if (digitalRead(cold) == HIGH)
  {
    setColdThreshold = true;
    setHotThreshold = false;
    lcd.clear();
    lcd.print("Setting Cold Threshold");
    delay(1000);
    lcd.clear();
    
    do {
      if (digitalRead(up) == HIGH)
      {
        coldThreshold += coldIncrement;
        delay(200);
      }
    
      if (digitalRead(down) == HIGH)
      {
        coldThreshold -= coldIncrement;
        delay(200);
      }
    } while (digitalRead(set) == LOW);
    
    setColdThreshold = false;
    lcd.clear();
    lcd.print("Threshold Set");
    delay(1000);
    lcd.clear();
  }
}

// Compute Distance for Ultrasonic Sensor
float getUltrasonicDistance(int trigPin, int echoPin)
{
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  long duration = pulseIn(echoPin, HIGH);
  float distance = duration * 0.034 / 2;
  return distance;
}

[bluejets]

Complete circuit diagram thanks...no fritzing please....Oh, and read the posting instructions.

[hatdogernshehe]

sorry for the messy diagram, i modified some of its connections in the actual wiring and i change the assigned pins also on the code.

[PerryBebbington]

Hello @hatdogernshehe,

The obvious thing that will make reading buttons difficult or impossible is the 500ms delay in your loop function. If a button is pressed during that delay (as it most probably will be) then it will be ignored. You have to press a button for at least 500ms to be sure it will be noticed. There are other delays of varing lengths elsewhere in your code, all of which will make reading buttons all but impossible.

Please start again with your code. You need to learn how to write collaborative, non-blocking code with no delays. Maybe start with:

Multi-tasking the Arduino - Part 1

Using millis for timing
Demonstration for several things at the same time
Finite state machine tutorial

Timer counter state change toggle FSM - all at once

There is a recurring theme of people new to Arduino and/or microcontrollers not grasping the concept of putting what I call ‘building blocks’ of code together to achieve some goal. These short sketches are an attempt to offer some examples showing how small pieces can be used in concert to build up larger, more complex sketches. Thanks to @PerryBebbington and @ballscrewbob for support and input. You made it better. The examples will illustrate: • Doing ‘several things at once’ • pitfalls of …

Write your code in small chunks, getting one thing at a time working before moving on.

[gilshultz]

Please post a schematic, one was requested without fritzing. Be sure it includes all connections, power, ground and power sources. Also add links to technical information on the hardware items you are using.