Arduino Micro microcontroller：Datasheet, Features, Applications[FAQs]

The Arduino Micro is a microcontroller development board designed around the ATmega32u4 chip and intended for projects requiring a very compact form factor. It represents Arduino's efforts to produce a minimalist board optimized for integration into small spaces.

At the core of the Micro is an 8-bit ATmega32u4 AVR RISC processor running at 16MHz and featuring 32KB of flash memory, 2.5KB of SRAM, and 1KB of EEPROM. The chip provides native USB functionality, eliminating the need for external USB communication chips. This allows the Micro to appear as a serial port to a connected computer as well as function as a mouse/keyboard.

Technical specifications of the ATmega32u4 microcontroller:

*Please note that these are the general specifications and the actual performance may vary depending on the specific model and usage conditions.

The compact Micro PCB measures just 48mm x 18mm and provides 20 digital I/O pins that can interface with external sensors, motors, lights, or other electronics. 7 of these pins support PWM output for modulation and control applications. There are 12 analog input pins for reading analog voltages. Power can be provided via USB or externally. The compact layout and surface mount components allow the Micro to be embedded into tight spaces or plugged into solderless breadboards.

*As the official partner of Arduino, Utmel provides you with official original Arduino products. Welcome to shop at the page dedicated to Arduino products.

-Microcontroller: ATmega32u4 with built-in USB support

-Operating Voltage: 5V

-Digital I/O Pins: 20

-PWM Pins: 7

-Analog Input Pins: 12

-Flash Memory: 32 KB

-SRAM: 2.5 KB

-EEPROM: 1 KB

-USB 2.0 interface

-Breadboard friendly design

-Surface mount components

-Wearable electronics projects

-Small robotics and IoT devices

-Miniaturized sensing systems

-Compact game controllers and HID devices

-Educational and prototyping uses

-Projects requiring breadboard compatibility

-Any application where a compact Arduino is needed

• Arduino Leonardo

• Arduino Micro without headers

• Arduino Nano

• Arduino Nano 33 BLE

• Arduino Nano 33 BLE Sense

• Arduino Nano 33 IoT

*Please note that these are the general specifications and the actual performance may vary depending on the specific model and usage conditions.

• Arduino Nano: This board is similar to the Arduino Micro in terms of capabilities but is in a smaller package. It is often used in breadboard projects due to its small footprint.

• Arduino Uno: This is the most common Arduino board and is a great alternative if you don't need the compact size of the Arduino Micro.

• Raspberry Pi Zero: Although not an Arduino, the Raspberry Pi Zero is a tiny, low-cost computer that can be used for a huge range of tasks.

• Adafruit Feather 32u4 Basic Proto: This is an Arduino-compatible development board from Adafruit that has a built-in USB and battery charging.

• Teensy LC: This board is similar to the Arduino Micro and is also compatible with the Arduino IDE. It offers a slightly different set of features and capabilities.

• SparkFun Pro Micro: This board is very similar to the Arduino Micro but is smaller and less expensive.

Password-Protected Door Lock System with Arduino and keypad

We will create a password-protected door lock system using Arduino and a keypad. As security concerns rise due to increasing theft rates, a digital code lock can provide an effective solution for your home or locker. The system will only unlock the door when the correct password is entered.

The project's circuit is straightforward, consisting of an Arduino, keypad module, buzzer, Servo Motor, and LCD. The Arduino controls all processes, including receiving the password from the keypad module, comparing passwords, operating the buzzer, rotating the servo motor, and displaying the status on the LCD. 

The keypad is used for inputting the password, the buzzer provides indications, the servo motor opens the gate through rotation, and the LCD displays status messages or notifications.

Required Components:

Here is a list of the components required for this project:

1. Arduino Board

2. 4x3 Keypad

3. 16x2 LCD Display

4. 10K Potentiometer

5. SG90 Servo Motor

6. 5V Buzzer

7. Connecting Wires

8. Breadboard

Circuit Diagram & Connections:

The schematic for the Password-Based Door Lock Security System is quite simple. The 4x3 keypad is connected to the Arduino using digital pins D1 to D7. The servo motor's PWM pin is connected to the Arduino's D9 digital pin. The positive wire of the buzzer is connected to the Arduino's D10 pin, and the negative wire is connected to the ground.

The 16x2 LCD is also connected to the Arduino as follows:

1. Connect pins 1,3,5,16 of LCD to GND.

2. Connect pins 2,15 of LCD to VCC (5V).

3. Connect pin 4 of LCD to pin A0 of Arduino.

4. Connect pin 6 of LCD to pin A1 of Arduino.

5. Connect pin 11 of LCD to pin A2 of Arduino.

6. Connect pin 12 of LCD to pin A3 of Arduino.

7. Connect pin 13 of LCD to pin A4 of Arduino.

8. Connect pin 14 of LCD to pin A5 of Arduino.

Working of Password-Based Door Lock Security System:

The default password "4567" is stored in the Arduino. You can change this in the code. When a password is entered, it is compared with the stored password in the Arduino. If it matches, the LCD displays 'Access Granted, Welcome' and the servo motor rotates 180 degrees to open the door. The door remains open for 5 seconds before automatically locking again.

If the entered password is incorrect, the LCD displays 'Code Incorrect, Go Away', and the buzzer beeps once when any key is pressed. 

Sample Code

#include <Keypad.h>
#include <Servo.h>
#include <LiquidCrystal.h>
const int servoPin = 9;
Servo lockServo;
const String password = "4567";
String input;
const byte ROW_NUM = 4; 
const byte COL_NUM = 4; 
char keys[ROW_NUM][COL_NUM] = {
  {'1','2','3'},
  {'4','5','6'},
  {'7','8','9'},
  {'*','0','#'}
};
byte pin_rows[ROW_NUM] = {9, 8, 7, 6}; 
byte pin_column[COL_NUM] = {5, 4, 3, 2}; 
Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COL_NUM);
LiquidCrystal lcd(A0, A1, A2, A3, A4, A5);
void setup(){
  lockServo.attach(servoPin);
  lockServo.write(0); // Lock
  lcd.begin(16, 2);
}
void loop(){
  char key = keypad.getKey();
  if (key){
    if (key == '#'){
      if (input == password){
        lcd.clear();
        lcd.print("Access Granted");
        lockServo.write(180); // Unlock
        delay(5000);
        lockServo.write(0); // Lock after 5 seconds
      }else{
        lcd.clear();
        lcd.print("Code Incorrect");
      }
      input = ""; // Clear input
    }else{
      input += key;
    }
  }
}

Source Code

The code for the Password-Based Door Lock Security System Using Arduino & Keypad can be found in the Keypad.h library and the original post. It can be copied, pasted, compiled, and uploaded to the ATmega328 microcontroller using the Arduino IDE.

EAGLE FILES IN .ZIP SCHEMATICS IN .PDF BOARD SIZE IN .DXF FRITZING IN .FZPZ

Tutorials:

1. Arduino’s official tutorials: This includes step-by-step instructions to get you started with Arduino, built-in examples, and tutorials on a number of libraries that come installed with the IDE.

2. Introduction to Arduino Micro: This tutorial discusses everything related to the Arduino Micro board including its main features, pinout, pin description, the software used, and applications.

3. Arduino Tutorial - Online Tutorials Library: This tutorial is intended for enthusiastic students or hobbyists. With Arduino, one can get to know the basics of microcontrollers and sensors very quickly and can start building prototypes with very little investment.

Projects:

1. The 25 Most Useful Arduino Projects in 2023: This article provides a list of useful projects you can do with a microcontroller.

2. 100 Best Arduino Projects for Beginners to Advance in 2023: This list is divided into 3 levels: Level 1 for beginners who are just starting their Arduino journey, and Level 2 for intermediate projects for those who have mastered all the basics of Arduino and Electronics.

3. 14 Great Arduino Projects for Beginners: This includes projects like an Arduino Lie Detector, an Arduino-Controlled RGB LED Infinity Mirror, a Neopixel Facemask Using Arduino, and more.

Resources:

1. Micro | Arduino Documentation: This is the official documentation for the Arduino Micro. It provides an overview of the board, its main features, setup guide, suggested libraries, built-in examples, language references, and more.

2. micro-ROS for Arduino - GitHub: This is a micro-ROS library for Arduino available on GitHub.