Circuit Documentation

Summary

This circuit is designed to interface an Arduino UNO with a variety of components including two servo motors, two LEDs (one red and one green), a set of resistors, and a 4×4 keypad. The Arduino UNO acts as the central controller, providing power and control signals to the servos, lighting up the LEDs, and receiving input from the keypad. The servos are powered by the Arduino's 5V output and are controlled via PWM signals. The LEDs are connected through resistors to limit the current and are controlled by digital outputs from the Arduino. The keypad is interfaced with multiple digital pins for detecting key presses.

Component List

Arduino UNO

• Microcontroller board based on the ATmega328P
• Provides power and control signals to the circuit

Servo (2 units)

• Actuators that can be positioned using PWM signals from the Arduino

LED: Two Pin (red)

• A red light-emitting diode that indicates status or provides feedback

LED: Two Pin (green)

• A green light-emitting diode that indicates status or provides feedback

Resistor (2 units)

• 220 Ohm resistors used to limit the current through the LEDs

4×4 Keypad

• An input device with 16 buttons arranged in a 4x4 matrix

Wiring Details

Arduino UNO

• 5V pin provides power to both Servo VCC pins
• GND pin is connected to the GND pins of both Servos, both LED cathodes, and the 4×4 Keypad
• D13 pin is connected to a 220 Ohm Resistor, which connects to the anode of the red LED
• D12 pin is connected to a 220 Ohm Resistor, which connects to the anode of the green LED
• D11 to D2 pins are connected to the 4×4 Keypad pins C4 to R4 respectively
• D10 and D9 pins provide PWM signals to the Servos

Servo

• VCC pin connected to Arduino's 5V
• GND pin connected to Arduino's GND
• PWM pin connected to Arduino's D10 or D9 for control

LED: Two Pin (red)

• cathode pin connected to Arduino's GND
• anode pin connected through a 220 Ohm Resistor to Arduino's D13

LED: Two Pin (green)

• cathode pin connected to Arduino's GND
• anode pin connected through a 220 Ohm Resistor to Arduino's D12

Resistor (220 Ohms)

• One end connected to Arduino's D13 or D12
• Other end connected to the anode of the red or green LED

4×4 Keypad

• C4 to R4 pins connected to Arduino's D11 to D2

Documented Code

Arduino UNO Code (sketch.ino)

void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}

This code is a template for the Arduino UNO and does not contain any functional code. It provides the basic structure with an empty setup() function, which runs once upon a reset or power-up, and an empty loop() function, which runs continuously after setup() completes. The user is expected to fill in these functions with code to control the servos, read the keypad, and manage the LEDs.