Circuit Documentation

Summary

This circuit integrates an Arduino Mega 2560 microcontroller with multiple peripherals including servos, an LCD I2C display, and an RFID-RC522 module. The servos are controlled via PWM signals from the Arduino, while the LCD display communicates over the I2C bus. The RFID-RC522 module interfaces with the Arduino through SPI communication for RFID reading capabilities.

Component List

Arduino Mega 2560

• Microcontroller board based on the ATmega2560
• Offers 54 digital input/output pins (of which 15 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button.

Servo (Generic)

• An actuator that can be precisely controlled for angular or linear position, velocity, and acceleration.
• Typically has three connections: power (VCC), ground (GND), and control (PWM).

Tower Pro SG90 Servo

• A small and lightweight servo motor capable of precise position control.
• Operates on +5V and uses a single control wire for PWM signal.

LCD I2C Display

• A liquid crystal display that communicates via the I2C bus protocol.
• Requires power (VCC), ground (GND), and two I2C lines (SDA for data, SCL for clock).

RFID-RC522

• An RFID reader/writer module that operates at 13.56 MHz.
• Interfaces with microcontrollers via SPI and requires power (VCC), ground (GND), reset (RST), and SPI lines (MISO, MOSI, SCK, SDA).

Wiring Details

Arduino Mega 2560

• GND: Connected to the ground pins of all Tower Pro SG90 servos, the LCD I2C display, and the RFID-RC522 module.
• 5V: Powers all Tower Pro SG90 servos and the LCD I2C display.
• 3V3: Powers the RFID-RC522 module.
• D21/SCL: Connected to the SCL pin of the LCD I2C display.
• D20/SDA: Connected to the SDA pin of the LCD I2C display.
• D6 PWM: Controls the signal pin of one Tower Pro SG90 servo.
• D7 PWM: Controls the signal pin of another Tower Pro SG90 servo.
• D41: Controls the signal pin of another Tower Pro SG90 servo.
• D35: Controls the signal pin of another Tower Pro SG90 servo.
• D52: Connected to the SCK pin of the RFID-RC522 module.
• D50: Connected to the MISO pin of the RFID-RC522 module.
• D53: Connected to the SDA pin of the RFID-RC522 module.
• D51: Connected to the MOSI pin of the RFID-RC522 module.
• D49: Connected to the RST pin of the RFID-RC522 module.

Tower Pro SG90 Servo

• GND: Connected to the ground (GND) on the Arduino Mega 2560.
• +5V: Powered by the 5V output from the Arduino Mega 2560.
• Signal: Controlled by a PWM output from the Arduino Mega 2560 (D6, D7, D41, or D35).

LCD I2C Display

• GND: Connected to the ground (GND) on the Arduino Mega 2560.
• VCC: Powered by the 5V output from the Arduino Mega 2560.
• SDA: Connected to the D20/SDA pin on the Arduino Mega 2560.
• SCL: Connected to the D21/SCL pin on the Arduino Mega 2560.

RFID-RC522

• VCC (3.3V): Powered by the 3.3V output from the Arduino Mega 2560.
• RST: Connected to the D49 pin on the Arduino Mega 2560.
• GND: Connected to the ground (GND) on the Arduino Mega 2560.
• IRQ: Not connected in this circuit.
• MISO: Connected to the D50 pin on the Arduino Mega 2560.
• MOSI: Connected to the D51 pin on the Arduino Mega 2560.
• SCK: Connected to the D52 pin on the Arduino Mega 2560.
• SDA: Connected to the D53 pin on the Arduino Mega 2560.

Documented Code

Arduino Mega 2560 - sketch.ino

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

}

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

}

Arduino Mega 2560 - documentation.txt

(No additional documentation provided)