Circuit Documentation

Summary

This circuit is designed to control a 28BYJ-48 stepper motor using an Arduino UNO. The motor is driven by a ULN2003 driver. The speed and direction of the motor are controlled by two pushbuttons. A phototransistor is used to detect light intensity and can be used to trigger motor actions based on light levels.

Component List

1. Arduino UNO

   • Description: Microcontroller board based on the ATmega328P.
   • 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

2. Phototransistor

   • Description: Light-sensitive transistor.
   • Pins: C, E

3. 28BYJ-48 Stepper Motor

   • Description: 5V stepper motor.
   • Pins: BLUE, PINK, YELLOW, ORANGE, RED

4. Pushbutton (1)

   • Description: Momentary pushbutton switch.
   • Pins: Pin 2, Pin 1, Pin 3, Pin 4

5. Pushbutton (2)

   • Description: Momentary pushbutton switch.
   • Pins: Pin 2, Pin 1, Pin 3, Pin 4

6. ULN 2003

   • Description: High-voltage, high-current Darlington transistor array.
   • Pins: IN1, IN2, IN3, IN4, IN5, IN6, IN7, GND, +, COIL1, COIL2, COIL3, COIL4, COIL5

7. Resistor

   • Description: 10k Ohm resistor.
   • Pins: pin1, pin2
   • Properties: Resistance: 10k Ohms

Wiring Details

Arduino UNO

• 5V connected to + of ULN 2003
• GND connected to GND of ULN 2003 and pin2 of Resistor
• A0 connected to E of Phototransistor
• D7 connected to Pin 1 of Pushbutton (1)
• D6 connected to Pin 1 of Pushbutton (2)
• D5 connected to IN4 of ULN 2003
• D4 connected to IN3 of ULN 2003
• D3 connected to IN2 of ULN 2003
• D2 connected to IN1 of ULN 2003

Phototransistor

• E connected to A0 of Arduino UNO
• C connected to pin1 of Resistor

28BYJ-48 Stepper Motor

• BLUE connected to COIL1 of ULN 2003
• PINK connected to COIL2 of ULN 2003
• YELLOW connected to COIL3 of ULN 2003
• ORANGE connected to COIL4 of ULN 2003
• RED connected to COIL5 of ULN 2003

Pushbutton (1)

• Pin 1 connected to D7 of Arduino UNO
• Pin 4 connected to GND of Arduino UNO

Pushbutton (2)

• Pin 1 connected to D6 of Arduino UNO
• Pin 4 connected to GND of Arduino UNO

ULN 2003

• + connected to 5V of Arduino UNO
• GND connected to GND of Arduino UNO and pin2 of Resistor
• IN1 connected to D2 of Arduino UNO
• IN2 connected to D3 of Arduino UNO
• IN3 connected to D4 of Arduino UNO
• IN4 connected to D5 of Arduino UNO
• COIL1 connected to BLUE of 28BYJ-48 Stepper Motor
• COIL2 connected to PINK of 28BYJ-48 Stepper Motor
• COIL3 connected to YELLOW of 28BYJ-48 Stepper Motor
• COIL4 connected to ORANGE of 28BYJ-48 Stepper Motor
• COIL5 connected to RED of 28BYJ-48 Stepper Motor

Resistor

• pin1 connected to C of Phototransistor
• pin2 connected to GND of Arduino UNO and GND of ULN 2003

Documented Code

/*
 * Arduino UNO Controlled Stepper Motor with Phototransistor and Pushbutton Inputs
 *
 * This code controls a stepper motor using an Arduino UNO. The motor is driven
 * by a ULN2003 driver. The speed and direction of the motor are controlled by
 * two pushbuttons. A phototransistor is used to detect light intensity and can
 * be used to trigger motor actions based on light levels.
 */

#include <Stepper.h>

// Define the number of steps per revolution for the stepper motor
#define STEPS_PER_REV 2048

// Define pin connections
const int motorPin1 = 2; // IN1 on ULN2003 to D2 on Arduino
const int motorPin2 = 3; // IN2 on ULN2003 to D3 on Arduino
const int motorPin3 = 4; // IN3 on ULN2003 to D4 on Arduino
const int motorPin4 = 5; // IN4 on ULN2003 to D5 on Arduino
const int button1Pin = 6; // Pushbutton 1 to D6 on Arduino
const int button2Pin = 7; // Pushbutton 2 to D7 on Arduino
const int photoPin = A0; // Phototransistor to A0 on Arduino

// Initialize the stepper library
Stepper stepper(STEPS_PER_REV, motorPin1, motorPin3, motorPin2, motorPin4);

void setup() {
  // Set up the motor pins as outputs
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
  pinMode(motorPin3, OUTPUT);
  pinMode(motorPin4, OUTPUT);

  // Set up the button pins as inputs
  pinMode(button1Pin, INPUT);
  pinMode(button2Pin, INPUT);

  // Initialize serial communication for debugging
  Serial.begin(9600);
}

void loop() {
  // Read the state of the pushbuttons
  int button1State = digitalRead(button1Pin);
  int button2State = digitalRead(button2Pin);

  // Read the value from the phototransistor
  int photoValue = analogRead(photoPin);

  // Print the phototransistor value to the serial monitor
  Serial.print("Light Intensity: ");
  Serial.println(photoValue);

  // Control the stepper motor based on button states
  if (button1State == HIGH) {
    // Rotate the motor clockwise
    stepper.step(1);
  } else if (button2State == HIGH) {
    // Rotate the motor counterclockwise
    stepper.step(-1);
  }

  // Add a small delay to debounce the buttons
  delay(50);
}

This documentation provides a comprehensive overview of the circuit, including a summary, detailed component list, wiring details, and the code used to control the circuit.