This document provides an overview of Arduino microcontroller systems. It defines Arduino as an open-source prototyping platform used to develop devices that can read inputs and provide outputs. Key components of the Arduino board are described, including the microcontroller, USB port, pins for digital and analog input/output. Basic concepts like circuits, sensors, actuators, serial communication protocols, memory and the embedded Arduino UNO board are explained at a high level. References for further reading are also provided.

1. CNET 315
Microprocessor & Assembly
Language
Phiros Mansur Nalakath
Course Coordinator
College of Computer Science & Information Technology,
Jazan University, KSA
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2. Chapter - 5
Arduino Microcontroller
Systems
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3. What is Arduino?
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 Arduino is an open-source prototyping platform in
electronics based on easy-to-use hardware and
software.
 Arduino is a microcontroller based prototyping board
which can be used in developing digital devices that
can read inputs like finger on a button, touch on a
screen, light on a sensor etc.
 Turning it in to output like switching on an LED,
rotating a motor, playing songs through a speaker etc.

4. Introduction to Arduino
Board
 The Arduino board can be programmed to do
anything by simply programming the
microcontroller on board using a set of instructions
 Arduino board consists of a USB plug to
communicate with the computer
 A bunch of connection sockets that can be wired to
external devices like motors, LEDs etc.
 Arduino aims to introduce the world of electronics
to people who have small to no experience in
electronics like hobbyists, designers, artists etc.
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5. Introduction to Arduino
Board
 Arduino boards are generally based on
microcontrollers from Atmel Corporation like 8,
16 or 32 bit AVR architecture based
microcontrollers.
 The important feature of the Arduino boards is
the standard connectors.
 Using these connectors, we can connect the
Arduino board to other devices like LEDs or add-
on modules called Shields.
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6. Key components of an
Arduino board.
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7. Key components of an
Arduino board
 1. Microcontroller - this is the brain of an Arduino, and is
the component that we load programs into. Think of it as a
tiny computer, designed to execute only a specific number
of things.
 2. USB port - used to connect your Arduino board to a
computer.
 3. USB to Serial chip - the USB to Serial is an important
component, as it helps translating data that comes from e.g.
a computer to the on-board microcontroller. This is what
makes it possible to program the Arduino board from your
computer.
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8. Key components of an
Arduino board
 4. Digital pins - pins that use digital logic (0,1 or
LOW/HIGH). Commonly used for switches and to turn
on/off an LED.
 5. Analog pins - pins that can read analog values in a 10
bit resolution (0-1023).
 6. 5V / 3.3V pins- these pins are used to power external
components.
 7. GND - also known as ground.
 8. VIN - stands for Voltage in, where you can connect
external power supplies.
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Depending on the Arduino board, you will find many more
components. The items listed above are generally found on any
Arduino board

9. Basic Operation
 Most Arduino boards are designed to have a single program
running on the microcontroller.
 The program can be designed to perform one single action,
such as blinking an LED.
 It can also be designed to execute hundreds of actions in a
cycle.
 The scope varies from one program to another.
 The program that is loaded to the microcontroller will start
execution as soon as it is powered.
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10. Basic operation of an
Arduino
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11. Circuit Basics
 Circuits consist of at least one active electronic component, and
a conductive material, such as wires, so that current can pass
through.
 When working with an Arduino, you will in most cases build a
circuit for your project.
 A simple example of a circuit, is an LED circuit.
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12. An LED circuit with an Arduino
 A wire is connected from a pin on the Arduino, to an LED via a
resistor (to protect the LED from high current), and finally to
the ground pin (GND).
 When the pin is set to a HIGH state, the microcontroller on
the Arduino board will allow an electric current to flow through
the circuit, which turns on the LED.
 When the pin is set to a LOW state, the LED will turn off, as
an electric current is not flowing through the circuit.
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13. Electronic Signals
 All communication between electronic
components are facilitated by electronic
signals.
 There are two main types of electronic
signals:
 Analog & Digital.
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14. Sensors & Actuators
 When working with Arduino, it is important to
understand sensors and actuators, and the difference
between them.
 What Is a Sensor?
 A sensor, in simple terms, is used to sense its environment,
meaning it records a physical parameter, for example
temperature, and converts it into an electronic signal.
 Sensors can also take the form of just a simple button:
when a state changes (we pressed a button), the electronic
signal is switched from low to high (0 to 1).
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15. What Is an Actuator?
An actuator, in simple terms, is used to actuate or change a
physical state. Some examples are:
 A light (such as an LED).
 A motor.
 A switch.
Actuators converts electric signals into e.g. radiant energy
(light) or mechanical energy (movement).
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16. Input & Output
 Sensors and actuators, are typically referred to
as inputs and outputs.
 In programs, it is common to construct conditionals
that checks the state of a sensor, and decides
whether it should actuate something.
 A basic example of this is a button and an LED.
 We can write a conditional that checks if a button is
pressed, turn on the LED, and turn it off if the button
is not pressed.
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17. Serial Communication
Protocols
 Serial communication protocols uses the digital signals to
send data.
 The most common are UART, SPI & I2C.
 UART(Universal Asynchronous Receiver/Transmitter) protocol
is used to send data between a computer and Arduino board.
 SPI : Serial Peripheral interface.
 I2C : Inter-Integrated Circuit
 The SPI and I2C protocols are used for communication
between both internal and external components.
 The communication is handled by something called a serial
bus, which is attached to a specific pin on the Arduino.
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18. Memory
 The "standard" Arduino typically has two memories:
SRAM and Flash memory.
 The SRAM (Static Random-Access Memory) is used to
store the value of a variable.
 When powered off, this memory resets.
 The Flash memory is primarily used to store the main
program, or the instructions for the microcontroller.
 This memory is not erased when powered off so that the
instructions for the microcontroller are executed as soon
as the board is powered
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19. Embedded Sensors
 Many new Arduino boards come equipped
with embedded sensors.
 For example, the Nano 33 BLE Sense has 7 embedded
sensors, but is only 45x18mm (the size of a thumb).
 These are all connected via the I2C protocol as mentioned
above, and has a unique address.
 Using the I2C protocol, we can connect several sensors on the
same pin, and retrieve the data accurately.
 Each device has an address that we need to specify in the
program, which we use when making data requests.
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20. Arduino UNO
 Arduino UNO is a basic and inexpensive Arduino board
and is the most popular of all the Arduino boards
 Arduino UNO is considered to be the best prototyping
board for beginners in electronics and coding.
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21. Arduino UNO
 Microcontroller used in UNO is ATmega328P, which
is an 8-bit microcontroller based on the AVR
architecture.
 UNO has 14 digital input – output (I/O) pins which
can be used as either input or output by connecting
them with different external devices and
components.
 Out of these 14 pins, 6 pins are capable of producing
PWM signal.
 All the digital pins operate at 5V and can output a
current of 20mA.
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22. 22
Pins and functions of Arduino

23. The Digital I/O pins functions
 Pins 0 and 1 are used for serial
communication. They are used to
receive and transmit serial data
 Pins 2 and 3 are used for external
interrupts.
 Six of the 14 digital I/O Pins i.e. 3, 5,
6, 9, 10, and 11 can provide 8-bit
PWM output.
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24. The Digital I/O pins functions
 Pins 10, 11, 12 and 13 (SS,
MOSI, MISO AND SCK
respectively) are used for SPI
communication.
 Pin 13 has a built-in LED
connected to it. When the pin is
HIGH, the LED is turned on and
when the pin is LOW, it is turned
off.
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25. References
 https://docs.arduino.cc/learn/starting-guide/getting-started-
arduino#overview
 https://docs.arduino.cc/learn/starting-guide/getting-started-
arduino#arduino-hardware-1
 https://docs.arduino.cc/learn/starting-guide/getting-started-
arduino#main-parts
 https://www.arduino.cc/reference/en/
 https://docs.arduino.cc/learn/starting-guide/getting-started-
arduino#a-typical-workflow
 https://docs.arduino.cc/learn/starting-guide/getting-started-
arduino#general
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26. The End
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