Introduction to Arduino
The Arduino is an open-source electronics platform. The open
source nature of Arduino has been the main attractive reason. Since it is an
Open Source project, all the files related to hardware and software is
available for personal or commercial use. The software files which includes all
the source code library are also open sourced.
It consists of both a physical programmable circuit board and a
software. It is very easy to do electronics
project using Arduino. Arduino boards are widely used in robotics, embedded
systems, and electronic projects where automation is an essential part of the
system.All Arduino boards have one thing in common which is a microcontroller.
A microcontroller is basically a really small computer. The Arduino software is
easy-to-use for beginners, yet flexible enough for advanced users. It runs on
Mac, Windows, and Linux. Arduino board designs use a variety of microprocessors
and controllers. The Arduino project provides an integrated development
environment (IDE) that runs on your computer, used to write and upload computer
code to the physical board. The microcontrollers can be programmed using the C
and C++ programming languages. Unlike most previous programmable circuit
boards, the Arduino does not need a separate piece of hardware in order to load
new code onto the board -- you can simply use a USB cable. The boards are
equipped with sets of digital and analog input/output (I/O) pins. Unlike other
controllers you don’t need to arrange extra peripherals and devices that makes
your project economical in nature and free from a lot of technical expertise.
When nature and functionality of the task go complex,Micro SD card can be added
in the boards to make them store more information.
Arduino UNO
The Arduino Uno is a microcontroller board based on the
ATmega328 . It contains everything needed to support the microcontroller. It
has 14 digital input/output pins, 6 analog inputs(A0 to A5), a 16 MHz crystal
oscillator, a USB connection, a power jack, an ICSP header, and a reset
button.Among this 14 I/O pins 6 can be used as PWM pins(pins 3,5,6,9,10, 11)
these pins are configured to provided 8-bit output PWM. This Arduino board
includes an inbuilt LED and that is allied to pin-13 which is named as digital
pin 13.This LED can be operated based on the high and low values of the pin.
The RST pin of this board can be used to restart the program from the first
line of it's sketch. A reset button is not a power supply button and is
controlled by microcontroller. Note that this reset button cannot controlled or
changed by the program that we burn on bootloader.. AREF pin is also there,the term AREF stands
for Analog Reference Voltage which is a reference voltage for analog inputs.
Reset pin is added on the board that resets the board. It is very helpful when
running program goes too complex and hangs up the board. LOW value to the reset
pin will reset the controller. IOREF pin is very useful for providing voltage
reference to the board. A shield is used to read the voltage across this pin
which then select the proper power source. It can simply be connected to a
computer with a USB cable or power it with a AC-to-DC adapter or battery to get
started. The range of supplied input voltage to the board ranges from 7volts to
20volts. Only 5 V is required to turn the board on, which can be achieved
directly using USB port or external adopter, which can be regulated and limit
to 5 V or 3.3 V based on the requirement of the project. These pins come with
standard operating ratings ranging between 20mA to 40mA. Internal pull-up
resistors are used in the board that limits the current exceeding from the
given operating conditions. However, too much increase in current makes these
resisters useless and damages the device. The voltage provided by the power
jack can be accessed through this pin. However, the output voltage through this
pin to the board will be automatically set up to 5V. Four pins 10(SS),
11(MOSI), 12(MISO), 13(SCK) provide SPI communication with the help of SPI
library. TWI (Two-wire
Interface)communication is accessed through Wire Library. A4 and A5 pins are
used for this purpose. Serial communication is carried out through two pins
called Pin 0 (Rx) and Pin 1 (Tx).Rx pin is used to receive data while Tx pin is
used to transmit data. If LEDs placed on the Rx and Tx pins will flash, they
indicate the transmission of data.Pin 2 and 3 are used for providing external
interrupts. An interrupt is called by providing LOW or changing value. 13KB of
flash memory is used to store the number of instructions in the form of code.
There are many versions of Uno boards available, however,
Arduino Nano V3 and Arduino Uno are the most official versions that come with
Atmega328 8-bit AVR Atmel microcontroller where RAM memory is 32KB.The Uno
differs from all preceding boards in that it does not use the FTDI
USB-to-serial driver chip. Instead, it features the Atmega8U2 programmed as a
USB-to-serial converter. The Arduino Uno has a number of facilities for
communicating with a computer, another Arduino, or other microcontrollers. The
ATmega328 provides UART TTL (5V) serial communication, which is available on
digital pins 0 (RX) and 1 (TX). An ATmega8U2 on the board channels this serial
communication over USB and appears as a virtual com port to software on the
computer. The '8U2 firmware uses the standard USB COM drivers, and no external
driver is needed.The Arduino software includes a serial monitor which allows
simple textual data to be sent to and from the Arduino board. The RX and TX
LEDs on the board will flash when data is being transmitted via the
USB-toserial chip and USB connection to the computer (but not for serial
communication on pins 0 and 1). A SoftwareSerial library allows for serial
communication on any of the Uno's digital pins. The ATmega328 also support I2C
(TWI) and SPI communication. The Arduino software includes a Wire library to
simplify use of the I2C bus. SPI communication is also there.The ATmega328 on
the Arduino Uno comes preburned with a bootloader that allows you to upload new
code to it without the use of an external hardware programmer.
•
Microcontroller ATmega328
• Operating
Voltage 5V
• Input
Voltage (recommended) 7-12V
• Input
Voltage (limits)
6-20V
• Digital I/O
Pins 14
• PWM
pins
6(3,5,6,9,10,11pins)
• Analog Input Pins 6
• DC Current
per I/O Pin 40 mA
• DC Current
for 3.3V Pin 50 mA
• Flash Memory 32 KB of which 0.5 KB
(used by bootloader)
• SRAM
2 KB
• EEPROM 1
KB
• Clock
Speed
16 MHz
• The length
of this board 68.6
mm
• The width of
this board 53.3mm
Arduino MEGA
The Arduino Mega is similar to the UNO’s big brother.The
Arduino Mega 2560 is an open-source microcontroller board based on the
ATmega2560. It has 54 digital input/output pins (of which 15 can be used as PWM
outputs), There are 16-analog pins included on the board which is marked as
A0-A15. It is very important to know that all the analog pins on this board can
be utilized like digital I/O pins. Every analog pin is accessible with the
10-bit resolution which can gauge from GND to 5 volts. But, the higher value
can be altered using AREF pin as well as the function of analog Reference.4
UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a
power jack, an ICSP header, and a reset button. It contains everything needed
to support the microcontroller; simply connect it to a computer with a USB
cable or power it with a AC-to-DC adapter or battery to get started. Vin Pin
supplies input voltage to the board ranges from 7volts to 20volts. The voltage
provided by the power jack can be accessed through this pin. However, the
output voltage through this pin to the board will be automatically set up to
5V.
Serial Communication is possible for that the serial pins of
this board like TXD and RXD are used to transmit & receive the serial data.
Tx indicates the transmission of information whereas the RX indicates receive
data. The serial pins of this board have four combinations. For serial 0, it
includes Tx (1) and Rx (0), for serial 1, it includes Tx(18) & Rx(19), for
serial 2 it includes Tx(16) & Rx(17), and finally for serial 3, it includes
Tx(14) & Rx(15).The external interrupts can be formed by using 6-pins like
interrupt 0(0), interrupt 1(3), interrupt 2(21), interrupt 3(20), interrupt
4(19), interrupt 5(18). These pins produce interrupts by a number of ways i.e.
Providing LOW value, rising or falling
edge or changing the value to the interrupt pins. An inbuilt led is there in
pin 13. The I2C communication can be supported by two pins namely 20 & 21
where 20-pin signifies Serial Data Line (SDA) which is used for holding the
data & 21-pin signifies Serial Clock Line (SCL ) mostly utilized for
offering data synchronization among the devices.SPI Communication is also
possible ,the term SPI is a serial peripheral interface which is used to transmit
the data among the controller & other components. Four pins like MISO (50),
MOSI (51), SCK (52), and SS (53) are utilized for the communication of SPI. The
dimension of Arduino Mega 2560 board mainly includes the length as well as
widths like 101.6mm or 4 inch X 53.34 mm or 2.1 inches.
•
Microcontroller ATmega2560
• Operating
Voltage 5V
• Input
Voltage (recommended) 7-12V
• Input
Voltage (limits) 6-20V
• Digital I/O
Pins 54
• PWM
pins
15
• Analog Input
Pins 16
• DC Current
per I/O Pin 40 mA
• DC Current
for 3.3V Pin 50 mA
• Flash Memory 256 KB of which 8KB used by bootloader
• SRAM
8 KB
• EEPROM 4
KB
• Clock
Speed
16 MHz
• The USB host
chip used MAX3421E
• The length of this board 4 inch
• The width of
this board 2.1
inches.
• The weight
of this board 36 g
Arduino NANO
The Arduino Nano is a small, complete, and
breadboard-friendly board based on the ATmega328 (Arduino Nano 3.x), an8 bit
AVR family microcontroller or ATmega168 (Arduino Nano 2.x). This board is quite
similar to other Arduino boards available in the market, but the small size
makes this board stand out from others. It has 22 input/output pins in total.
It contains 14 digital pins out of which 6 pins (3,5,6,9,10,11 )are used for
generating 8 bit PWM output.. There are 8 analog pins on the board marked as A0
– A7 pins. These pins are used to measure the analog voltage ranging between 0
to 5V with a total resolution of 10bits.Each of these Digital & Analog Pins
are assigned with multiple functions but their main function is to be
configured as input or output. It contain 2 Reset Pins & 6 Power. Reset pin
is added on the board that resets the board. It is very helpful when running
program goes too complex and hangs up the board. LOW value to the reset pin
will reset the controller. Pin 13 is used to turn on the built-in LED. Like uno
and mega board AREF pin is used as a reference voltage for the input voltage. .
It comes with an operating voltage of 5V, however, the input voltage can vary
from 7 to 12V. 5V is a regulated power supply voltage of the board that is used
to power the controller and other components placed on the board. 3.3V is the
minimum voltage generated by the voltage regulator on the board. Arduino Nano
comes with a crystal oscillator of frequency 16 MHz. It is used to produce a
clock of precise frequency using constant voltage. To connect the Arduino Nano
to your computer, this board doesn’t use standard USB for connection with a
computer, instead, it comes with Mini USB support. This also provides power to
the board, as indicated by the blue LED (which is on the bottom of the Arduino
Nano 2.x and the top of the Arduino Nano 3.0). The Arduino Nano can be powered
via the Mini-B USB connection, 6-20V unregulated external power supply (pin
30), or 5V regulated external power supply (pin 27). The power source is
automatically selected to the highest voltage source. So you can connect
battery positive to Vin pin and negative to Ground pin directly.
Tx pins are used for serial communication where Tx
represents the transmission of data while Rx represents the data receiver. Four
pins 10(SS),11(MOSI),12(MISO),13(SCK) are used for SPI (Serial Peripheral
Interface). SPI is an interface bus and mainly used to transfer data between
microcontrollers and other peripherals like sensors, registers, and SD card.
Pin 2 and 3 are used as external interrupts which are used in case of emergency
when we need to stop the main program and call important instructions at that
point. The main program resumes once interrupt instruction is called and
executed.I2C communication is developed using A4 and A5 pins where A4
represents the serial data line (SDA) which carries the data and A5 represents
the serial clock line (SCL) which is a clock signal, generated by the master
device, used for data synchronization between the devices on an I2C bus.
•
Microcontroller
ATmega328P(Arduino Nano 3.x)
• Operating
Voltage 5V
• Input
Voltage(Recommended) 7-12V
• Analog Input
Pins 6 (A0 – A5)
• Digital I/O
Pins 14
• PWM pins 6
(pins3,5,6,9,10,11)
• DC Current
on I/O Pins 40 mA
• DC Current
on 3.3V Pin 50 mA
• Flash
Memory 3KB (2KBisused for Bootloader)
• SRAM
2 KB
• EEPROM 1 KB
• Frequency
(Clock Speed) 16 MHz
•
Communication IIC, SPI,
USART
•
Dimension 43.18
mm×18.54 mm
.
