Arduino Servo Motor 7-Segment Display | Counting from 0 to 9

Arduino project that uses a servo motor and a 7-segment display to count from 0 to 9.

Here’s a complete breakdown so you can both understand it and build it.

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1. Project Overview

In this project:

• The Arduino will count from 0 to 9.
• The 7-segment display will show the number.
• The servo motor will move to a specific position for each number.

For example:

• When the display shows 0, the servo is at 0°.
• When the display shows 5, the servo is at 90°.
• When the display shows 9, the servo is at 180°.

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2. Components Needed

• Arduino Uno (or compatible)
• SG90 or MG90S Servo motor
• Common cathode or common anode 7-segment display
• 220Ω resistors (x7)
• Breadboard + jumper wires
• USB cable for Arduino

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3. Circuit Wiring

7-Segment Display (Common Cathode example)

Let’s assign Arduino pins for each segment:

Segment	Arduino Pin
A	2
B	3
C	4
D	5
E	6
F	7
G	8

Common cathode pin → GND.

Servo Motor

• Signal pin → Arduino pin 9
• Vcc → 5V
• GND → GND

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4. Arduino Code

cppCopyEdit#include <Servo.h>

Servo myServo;

// Segment pin order: A, B, C, D, E, F, G
int segmentPins[] = {2, 3, 4, 5, 6, 7, 8};

// Number patterns for 0–9 (common cathode)
byte numbers[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() {
  // Set all segment pins as output
  for (int i = 0; i < 7; i++) {
    pinMode(segmentPins[i], OUTPUT);
  }
  
  myServo.attach(9); // Servo signal pin
}

void loop() {
  for (int num = 0; num <= 9; num++) {
    displayNumber(num);
    
    // Map number 0–9 to servo angle 0–180
    int angle = map(num, 0, 9, 0, 180);
    myServo.write(angle);

    delay(1000); // Wait 1 second before next number
  }
}

void displayNumber(int num) {
  for (int seg = 0; seg < 7; seg++) {
    digitalWrite(segmentPins[seg], numbers[num][seg]);
  }
}

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5. How It Works

1. The numbers array defines which segments light up for each digit.
2. In the loop(), the Arduino counts from 0 to 9.
3. For each number:
   • displayNumber(num) lights up the correct segments.
   • The servo moves to a mapped position based on the number.
4. After a short delay, it moves to the next number.

source by https://www.youtube.com/shorts/aSGwVuYEXBg