Circuit Documentation

Summary

This circuit is designed to control a solenoid valve based on water flow and water level sensors. It uses an Arduino UNO as the main microcontroller, interfacing with various sensors and modules including a Bluetooth module, an OLED display, a relay module, and LEDs for status indication. The system can receive desired water volume via Bluetooth and display real-time data on the OLED screen. The solenoid valve is controlled based on the water flow and level readings.

Component List

1. HC-05 Bluetooth Module

   • Description: Bluetooth module for wireless communication.
   • Pins: Key, VCC, GND, TXD, RXD, State

2. Solenoid Valve 12V

   • Description: Electromechanical valve controlled by a 12V power supply.
   • Pins: GND, 12V

3. 1 Channel 5V Relay Module

   • Description: Relay module to control high voltage devices.
   • Pins: VCC+, VCC- (GND), IN, N.O., COM, N.C.

4. 12V Power Supply

   • Description: Power supply providing 12V DC.
   • Pins: +, -

5. OLED Display 128x32

   • Description: OLED display for visual output.
   • Pins: SDA, SCL, VCC, GND

6. 4x4 Keypad (Simulator)

   • Description: Keypad for user input.
   • Pins: R1, C4, R2, C2, R3, R4, C1, C3

7. Ultrasonic Sensor

   • Description: Sensor for measuring distance.
   • Pins: +VCC, Trigger, Echo, GND

8. Water Flow Sensor

   • Description: Sensor for measuring water flow rate.
   • Pins: Signal, Vcc, GND

9. LED: Two Pin (Red)

   • Description: Red LED for status indication.
   • Pins: Cathode, Anode

10. LED: Two Pin (Green)

    • Description: Green LED for status indication.
    • Pins: Cathode, Anode

11. LED: Two Pin (Yellow)

    • Description: Yellow LED for status indication.
    • Pins: Cathode, Anode

12. Water Level Sensor

    • Description: Sensor for measuring water level.
    • Pins: SIG, VCC, GND

13. Buzzer

    • Description: Buzzer for audible alerts.
    • Pins: Positive, Negative

14. Arduino UNO

    • Description: Main microcontroller.
    • Pins: UNUSED, IOREF, Reset, 3.3V, 5V, GND, Vin, A0, A1, A2, A3, A4, A5, SCL, SDA, AREF, D13, D12, D11, D10, D9, D8, D7, D6, D5, D4, D3, D2, D1, D0

Wiring Details

HC-05 Bluetooth Module

• VCC to Arduino UNO 5V
• GND to Arduino UNO GND
• TXD to Arduino UNO D0
• RXD to Arduino UNO D1
• State to Arduino UNO D11
• Key to Arduino UNO D10

Solenoid Valve 12V

• GND to 1 Channel 5V Relay Module N.O.
• 12V to 1 Channel 5V Relay Module COM

1 Channel 5V Relay Module

• VCC+ to Arduino UNO 5V
• VCC- (GND) to Arduino UNO GND
• IN to Arduino UNO D7
• N.O. to Solenoid Valve GND
• COM to Solenoid Valve 12V

12V Power Supply

• + to 1 Channel 5V Relay Module COM
• - to 1 Channel 5V Relay Module N.O.

OLED Display 128x32

• VCC to Arduino UNO 5V
• GND to Arduino UNO GND
• SCL to Arduino UNO SCL
• SDA to Arduino UNO SDA

4x4 Keypad (Simulator)

• C1 to Arduino UNO A0
• C2 to Arduino UNO A1
• C3 to Arduino UNO A2
• C4 to Arduino UNO A3
• R1 to Arduino UNO D3
• R2 to Arduino UNO D4
• R3 to Arduino UNO D5
• R4 to Arduino UNO D6

Ultrasonic Sensor

• +VCC to Arduino UNO 5V
• GND to Arduino UNO GND
• Trigger to Arduino UNO D8
• Echo to Arduino UNO D9

Water Flow Sensor

• Vcc to Arduino UNO 5V
• GND to Arduino UNO GND
• Signal to Arduino UNO D2

LED: Two Pin (Red)

• Anode to Arduino UNO D13
• Cathode to Arduino UNO GND

LED: Two Pin (Green)

• Anode to Arduino UNO D12
• Cathode to Arduino UNO GND

LED: Two Pin (Yellow)

• Anode to Arduino UNO D13
• Cathode to Arduino UNO GND

Water Level Sensor

• VCC to Arduino UNO 5V
• GND to Arduino UNO GND
• SIG to Arduino UNO D2

Buzzer

• Positive to Arduino UNO 5V
• Negative to Arduino UNO GND

Code Documentation

#include <SoftwareSerial.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 32
#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

SoftwareSerial BTSerial(0, 1); // RX, TX

const int relayPin = 7;
const int waterLevelSensorPin = 2;
const int flowSensorPin = 2;
const int buzzerPin = 8;
const int redLEDPin = 13;
const int yellowLEDPin = 12;
const int greenLEDPin = 11;

volatile int flowPulseCount = 0;
float flowRate = 0.0;
float totalLitres = 0.0;
float desiredLitres = 0.0;

void setup() {
  pinMode(relayPin, OUTPUT);
  pinMode(waterLevelSensorPin, INPUT);
  pinMode(flowSensorPin, INPUT);
  pinMode(buzzerPin, OUTPUT);
  pinMode(redLEDPin, OUTPUT);
  pinMode(yellowLEDPin, OUTPUT);
  pinMode(greenLEDPin, OUTPUT);

  attachInterrupt(digitalPinToInterrupt(flowSensorPin), flowPulseCounter, RISING);

  BTSerial.begin(9600);
  Serial.begin(9600);

  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);
  display.display();
  delay(2000);
  display.clearDisplay();
}

void loop() {
  if (BTSerial.available()) {
    desiredLitres = BTSerial.parseFloat();
  }

  flowRate = (flowPulseCount / 7.5); // Example conversion factor
  totalLitres += (flowRate / 60);

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.print("Flow Rate: ");
  display.print(flowRate);
  display.print(" L/min");
  display.setCursor(0, 10);
  display.print("Total: ");
  display.print(totalLitres);
  display.print(" L");
  display.display();

  if (totalLitres >= desiredLitres) {
    digitalWrite(relayPin, LOW);
    digitalWrite(buzzerPin, HIGH);
  } else {
    digitalWrite(relayPin, HIGH);
    digitalWrite(buzzerPin, LOW);
  }

  // LED Indicators for Water Level
  if (totalLitres < desiredLitres * 0.33) {
    digitalWrite(redLEDPin, HIGH);
    digitalWrite(yellowLEDPin, LOW);
    digitalWrite(greenLEDPin, LOW);
  } else if (totalLitres < desiredLitres * 0.66) {
    digitalWrite(redLEDPin, LOW);
    digitalWrite(yellowLEDPin, HIGH);
    digitalWrite(greenLEDPin, LOW);
  } else {
    digitalWrite(redLEDPin, LOW);
    digitalWrite(yellow