Arduino and Robotics Projects

for Kids | Grade 5,6,7,8,9,10

Project Title

7-Segment Display using arduino.

Description

A 7-segment display is a simple electronic display device used to show numbers and limited characters.It is widely used in digital systems because of its low cost and easy interface.A 7-segment display consists of seven individual LED segments.These segments are arranged in a rectangular pattern.Each segment is labeled using letters from a to g.An additional segment called the decimal point (dp) is sometimes included.Each segment can be turned ON or OFF independently.By combining different segments,numbers from 0 to 9 can be displayed.The display is commonly used in electronic devices.Examples includes calculators,clocks,meters,and counters.

Components Used

Arduino Uno board
7-segment display
220Ω resistor
Breadboard
Jumper wires
USB cable programming

Connection Steps

7-segment pins(a-g)connection
Segment—-Ardunio Pin
a————-2
b————-3
c————-4
d————-5
e————-6
f————-7
g————-8
Common cathode pin–GND
Connect to the arduino UNO Board
Upload Arduino code

Arduino Code


// Pin definitions for segments a, b, c, d, e, f, g
int segments[] = {2, 3, 4, 5, 6, 7, 8};

// Array representing segments to turn ON for numbers 0-9
// 1 = ON, 0 = OFF (Common Cathode)
byte digits[10][7] = {
  {1, 1, 1, 1, 1, 1, 0}, // 0
  {0, 1, 1, 0, 0, 0, 0}, // 1
  {1, 1, 0, 1, 1, 0, 1}, // 2
  {1, 1, 1, 1, 0, 0, 1}, // 3
  {0, 1, 1, 0, 0, 1, 1}, // 4
  {1, 0, 1, 1, 0, 1, 1}, // 5
  {1, 0, 1, 1, 1, 1, 1}, // 6
  {1, 1, 1, 0, 0, 0, 0}, // 7
  {1, 1, 1, 1, 1, 1, 1}, // 8
  {1, 1, 1, 1, 0, 1, 1}  // 9
};

void setup() {
  for (int i = 0; i < 7; i++) {
    pinMode(segments[i], OUTPUT);
  }
}

void displayDigit(int digit) {
  for (int i = 0; i < 7; i++) {
    digitalWrite(segments[i], digits[digit][i]);
  }
}

void loop() {
  for (int i = 0; i < 10; i++) {
    displayDigit(i);
    delay(1000); // Wait 1 second
  }
}

Applications

Digital clocks and watches.
Electronic Counters.
Scoreboards.
Calculators.
Elevator floor display.
Voltage meters.
Timer system.

More about this Project name 7 segment display

What is 7-segment display?

A 7 segment display is an electronic display device made up of seven leds(segments)arranged in a rectangular pattern.Each segment is labeled from a to g,and by turning ON/OFF specific segments,you can display digits from 0 to 9.Some displays also include an eighth segment called the decimal point(dp).
There are two main types of 7 segment displays:-
1.Common Cathode(CC):All cathodes are connected together and tied to ground.A segment lights up when you apply HIGH(5V)to its pin.
2.Common Anode(CA):All anodes are connected together and tied to VCC(5V).A segment lights up when you apply LOW(0V)to its pin.

Working principle:-
Each segment of the display is controlled by one digital pin of the arduino.By sending HIGH or LOW Signals,you can turn individual segments ON or OFF.By combining multiple segments you form numbers. Each segment works like a small LED. When voltage is applied:-
1.Current flows
2.LED glows
By controlling each segment:
1.Different shapes are formed
2.Numbers are displayed
Example:
1.Number 0—all segments except g
2.Number 1—only b and c
3.Number 2—a,b,d,e,g
4.Number 8—all segments ON

Advantages:-

simple and low cost
Easy to interface with arduino
Good for beginners
Low power consumption
Good for numeric display

Disadvantages:-

1.Cannot display complex characters
2.Limited to numbers and few letters
3.Uses multiple pins
4.Not suitable for long text

Limitation:-

Can display only limited characters
Needs multiple pins
Not suitable for complex text display

7-Segment Display Using Arduino