Arduino Uno


What Is Arduino?


Arduino is an open source programmable circuit board that can be integrated into a wide variety of maker space projects both simple and complex.  This board contains a microcontroller which is able to be programmed to sense and control objects in the physical world.   By responding to sensors and inputs, the Arduino is able to interact with a large array of outputs such as LEDs, motors and displays.  Because of its flexibility and low cost, Arduino has become a very popular choice for makers and maker spaces looking to create interactive hardware projects.

Arduino was introduced back in 2005 in Italy by Massimo Banzi as a way for non-engineers to have access to a low cost, simple tool for creating hardware projects.  Since the board is open-source, it is released under a Creative Commons license which allows anyone to produce their own board.  If you search the web, you will find there are hundreds of Arduino compatible clones and variations available but the only official boards have Arduino in its name.


The Arduino UNO is the best board to get started with electronics and coding. If this is your first experience tinkering with the platform, the UNO is the most robust board you can start playing with. The UNO is the most used and documented board of the whole Arduino family.




Board Breakdown

Here are the components that make up an Arduino board and what each of their functions are.

  1. Reset Button– This will restart any code that is loaded to the Arduino board
  2. AREF– Stands for “Analog Reference” and is used to set an external reference voltage
  3. Ground Pin– There are a few ground pins on the Arduino and they all work the same
  4. Digital Input/Output–  Pins 0-13 can be used for digital input or output
  5. PWM– The pins marked with the (~) symbol can simulate analog output
  6. USB Connection– Used for powering up your Arduino and uploading sketches
  7. TX/RX– Transmit and receive data indication LEDs
  8. ATmega Microcontroller–  This is the brains and is where the programs are stored
  9. Power LED Indicator– This LED lights up anytime the board is plugged in a power source
  10. Voltage Regulator– This controls the amount of voltage going into the Arduino board
  11. DC Power Barrel Jack – This is used for powering your Arduino with a power supply
  12. 3V Pin– This pin supplies 3.3 volts of power to your projects
  13. 5V Pin– This pin supplies 5 volts of power to your projects
  14. Ground Pins–  There are a few ground pins on the Arduino and they all work the same
  15. Analog Pins–  These pins can read the signal from an analog sensor and convert it to digital




Arduino Uno Technical Specifications



ATmega328P – 8 bit AVR family microcontroller

Operating Voltage


Recommended Input Voltage


Input Voltage Limits


Analog Input Pins

6 (A0 – A5)

Digital I/O Pins

14 (Out of which 6 provide PWM output)

DC Current on I/O Pins

40 mA

DC Current on 3.3V Pin

50 mA

Flash Memory

32 KB (0.5 KB is used for Bootloader)


2 KB


1 KB

Frequency (Clock Speed)

16 MHz




How to Program Arduino

Once the circuit has been created on the breadboard, you’ll need to upload the program (known as a sketch) to the Arduino.  The sketch is a set of instructions that tells the board what functions it needs to perform.  An Arduino board can only hold and perform one sketch at a time.  The software used to create Arduino sketches is called the IDE which stands for Integrated Development Environment.  



The software is free to download and can be found at:


Every Arduino sketch has two main parts to the program:

void setup() – Sets things up that have to be done once and then don’t happen again.

void loop () – Contains the instructions that get repeated over and over until the board is turned off.



  • Prototyping of Electronics Products and Systems
  • Multiple DIY Projects.
  • Easy to use for beginner level DIYers and makers.
  • Projects requiring Multiple I/O interfaces and communications.