User Interface with Arduino

Introduction: User interfaces play a crucial role in electronic systems, as they provide users with a way to interact with devices and control their functionalities. In this article, we will explore the importance and usefulness of user interfaces in electronic projects and demonstrate how to create an effective user interface using Arduino.

Project: For this example, we will create a simple temperature monitoring system with a user interface. The objective is to display the current temperature on an LCD screen and allow the user to adjust temperature thresholds using push buttons. The system will also include an LED indicator that turns on when the temperature exceeds a certain threshold.

Components Required:

• Arduino Uno
• LCD screen (16x2)
• Breadboard
• Jumper wires
• 10k ohm potentiometer
• 220 ohm resistor
• Push buttons (2)
• LED
• Temperature sensor (e.g., LM35)

Examples:

1. Displaying Temperature on LCD:

   
   #include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() { lcd.begin(16, 2); }

void loop() { float temperature = readTemperature(); // Function to read temperature from sensor lcd.setCursor(0, 0); lcd.print("Temp: "); lcd.print(temperature); lcd.print(" C"); delay(1000); }

float readTemperature() { // Code to read temperature from sensor and return the value }

This code initializes the LCD screen and continuously reads the temperature from the sensor, displaying it on the screen.

2. Adjusting Temperature Thresholds:
```C++
int threshold = 25; // Initial temperature threshold
int buttonPin = 7; // Pin connected to the push button

void setup() {
  pinMode(buttonPin, INPUT_PULLUP);
}

void loop() {
  if (digitalRead(buttonPin) == LOW) {
    threshold += 5; // Increase threshold by 5 degrees
    delay(200); // Debounce delay
  }
  // Rest of the code to handle threshold adjustment
}

This code demonstrates how to increase the temperature threshold by 5 degrees when a push button is pressed. You can modify it to decrease the threshold or adjust it in smaller increments.

3. LED Indicator for Threshold Exceeded:

   
   int ledPin = 8; // Pin connected to the LED

void setup() { pinMode(ledPin, OUTPUT); }

void loop() { float temperature = readTemperature();

if (temperature > threshold) { digitalWrite(ledPin, HIGH); // Turn on LED if temperature exceeds threshold } else { digitalWrite(ledPin, LOW); } // Rest of the code for temperature monitoring }

This code checks if the current temperature exceeds the threshold and turns on an LED accordingly. You can modify it to add additional functionality or notifications.