Skip to main content

Arduino

Arduino

Arduino is a software company, project, and user community that designs and manufactures computer hardware, open, and microcontroller-based kits for building digital devices and interactive objects that can sense and control physical devices.

The project is based on microcontroller board designs, produced by several vendors, using various microcontrollers. These systems provide sets of digital and analog I/O pins that can interface to various expansion boards (termed shields) and other circuits. The boards feature serial communication interfaces, including Universal Serial Bus (USB) on some models, for loading programs from personal computers. For programming the microcontrollers, the Arduino project provides an integrated development environment (IDE) based on a programming language named Processing, which also supports the languages, C and C++.
The first Arduino was introduced in 2005, aiming to provide a low cost, easy way for novices and professionals to create devices that interact with their environment using sensors and actuators. Common examples of such devices intended for beginner hobbyists include simple robots, thermostats, and motion detectors.
Arduino boards are available commercially in preassembled form, or as do-it-yourself kits. The hardware design specifications are openly available, allowing the Arduino boards to be produced by anyone. Adafruit Industries estimated in mid-2011 that over 300,000 official Arduinos had been commercially produced, and in 2013 that 700,000 official boards were in users' hands.

History
Colombian student Hernando Barragán created the development platform Wiring as his Master's thesis project in 2004 at the Interaction Design Institute Ivrea in Ivrea, Italy. Massimo Banzi and Casey Reas (known for his work on Processing) were supervisors for his thesis. The goal was to create low cost, simple tools for non-engineers to create digital projects. The Wiring platform consisted of a hardware PCB with an ATmega128 microcontroller, an integrated development environment (IDE) based on Processing and library functions to easily program the microcontroller.

In 2005, Massimo Banzi, with David Mellis (then an IDII student) and David Cuartielles, added support for the cheaper ATmega8 microcontroller to Wiring. But instead of continuing the work on Wiring, they forked (or copied) the Wiring source code and started running it as a separate project, called Arduino.
The Arduino's initial core team consisted of Massimo Banzi, David Cuartielles, Tom Igoe, Gianluca Martino, and David Mellis.
The name Arduino comes from a bar in Ivrea, where some of the founders of the project used to meet. The bar was named after Arduin of Ivrea, who was the margrave of the March and King of Italy from 1002 to 1014.
Following the completion of the Wiring platform, its lighter, lower cost versions were created and made available to the open-source community. Associated researchers, including David Cuartielles, promoted the idea. Arduino's initial core team consisted of Massimo Banzi, David Cuartielles, Tom Igoe, Gianluca Martino, and David Mellis.

Hardware
 An Arduino board historically consists of an Atmel 8-, 16- or 32-bit AVR microcontroller (although since 2015 other makers' microcontrollers have been used) with complementary components that facilitate programming and incorporation into other circuits. An important aspect of the Arduino is its standard connectors, which let users connect the CPU board to a variety of interchangeable add-on modules termed shields. Some shields communicate with the Arduino board directly over various pins, but many shields are individually addressable via an I²C serial bus—so many shields can be stacked and used in parallel. Before 2015, Official Arduinos had used the Atmel megaAVR series of chips, specifically the ATmega8, ATmega168, ATmega328, ATmega1280, and ATmega2560. In 2015, units by other producers were added. A handful of other processors have also been used by Arduino compatible devices. Most boards include a 5 V linear regulator and a 16 MHz crystal oscillator (or ceramic resonator in some variants), although some designs such as the LilyPad run at 8 MHz and dispense with the onboard voltage regulator due to specific form-factor restrictions. An Arduino's microcontroller is also pre-programmed with a boot loader that simplifies uploading of programs to the on-chip flash memory, compared with other devices that typically need an external programmer. This makes using an Arduino more straightforward by allowing the use of an ordinary computer as the programmer. Currently, optiboot bootloader is the default bootloader installed on Arduino UNO.

At a conceptual level, when using the Arduino integrated development environment, all boards are programmed over a serial connection. Its implementation varies with the hardware version. Some serial Arduino boards contain a level shifter circuit to convert between RS-232logic levels and transistor–transistor logic (TTL) level signals. Current Arduino boards are programmed via Universal Serial Bus (USB), implemented using USB-to-serial adapter chips such as the FTDI FT232. Some boards, such as later-model Uno boards, substitute the FTDI chip with a separate AVR chip containing USB-to-serial firmware, which is reprogrammable via its own ICSP header. Other variants, such as the Arduino Mini and the unofficial Boarduino, use a detachable USB-to-serial adapter board or cable, Bluetooth or other methods, when used with traditional microcontroller tools instead of the Arduino IDE, standard AVR in-system programming (ISP) programming is used.
The Arduino board exposes most of the microcontroller's I/O pins for use by other circuits. The Diecimila, Duemilanove, and current Uno provide 14 digital I/O pins, six of which can produce pulse-width modulated signals, and six analog inputs, which can also be used as six digital I/O pins. These pins are on the top of the board, via female 0.1-inch (2.54 mm) headers. Several plug-in application shields are also commercially available. The Arduino Nano, and Arduino-compatible Bare Bones Board and Boarduino boards may provide male header pins on the underside of the board that can plug into solderless breadboards.
Many Arduino-compatible and Arduino-derived boards exist. Some are functionally equivalent to an Arduino and can be used interchangeably. Many enhance the basic Arduino by adding output drivers, often for use in school-level education, to simplify making buggies and small robots. Others are electrically equivalent but change the form factor, sometimes retaining compatibility with shields, sometimes not. Some variants use different processors, of varying compatibility.


Official boards
The original Arduino hardware was produced by the Italian company Smart Projects. Some Arduino-branded boards have been designed by the American companies SparkFun Electronics and Adafruit Industries. As of 2016, 17 versions of the Arduino hardware had been commercially produced.
·         Example Arduino boards

  •  Arduino Diecimila in Stoicheia


  • Arduino Duemilanove (rev 2009b)


  • Arduino UNO


  • Arduino Leonardo


  • Arduino Mega


  • Arduino MEGA 2560 R3 (front side)


  • Arduino MEGA 2560 R3 (back side)


  • Arduino Nano


  • Arduino Due
          (ARM Cortex-M3 core)

  • LilyPad Arduino (rev 2007)


  • Arduino Yun


Software


Arduino programs may be written in any programming language with a compiler that produces binary machine code. Atmel provides a development environment for their microcontrollers, AVR Studio and the newer Atmel Studio.

The Arduino project provides the Arduino integrated development environment (IDE), which is a cross-platform application written in the programming language Java. It originated from the IDE for the languages Processing and Wiring. It is designed to introduce programming to artists and other newcomers unfamiliar with software development. It includes a code editor with features such assyntax highlighting, brace matching, and automatic indentation, and provides simple one-click mechanism to compile and load programs to an Arduino board. A program written with the IDE for Arduino is called a "sketch".
The Arduino IDE supports the languages C and C++ using special rules to organize code. The Arduino IDE supplies a software library called Wiring from the Wiring project, which provides many common input and output procedures. A typical Arduino C/C++ sketch consist of two functions that are compiled and linked with a program stub main() into an executable cyclic executive program:
·         setup(): a function that runs once at the start of a program and that can initialize settings.
·         loop(): a function called repeatedly until the board powers off.
After compiling and linking with the GNU toolchain, also included with the IDE distribution, the Arduino IDE employs the programavrdude to convert the executable code into a text file in hexadecimal coding that is loaded into the Arduino board by a loader program in the board's firmware.

Sample program

A typical program for a beginning Arduino programmer blinks a light-emitting diode (LED) on and off. This program is usually loaded in the Arduino board by the manufacturer. In the Arduino environment, a user might write such a program as shown.
#define LED_PIN 13
 
void setup() {
    pinMode(LED_PIN, OUTPUT);       // Enable pin 13 for digital output
}
 
void loop() {
    digitalWrite(LED_PIN, HIGH);    // Turn on the LED
    delay(1000);                    // Wait one second (1000 milliseconds)
    digitalWrite(LED_PIN, LOW);     // Turn off the LED
    delay(1000);                    // Wait one second
}

Power LED (red) and integrated LED on Line 13 (green) on Arduino compatible board, made in China

Most Arduino boards contain an LED and a load resistor connected between pin 13 and ground which is a convenient feature for many tests.

Comments

Post a Comment

Popular posts from this blog

Project #2: Repeating with for Loops When designing a sketch, you’ll often repeat the same function. You could simply copy and paste the function to duplicate it in a sketch, but that’s inefficient and a waste of your Arduino’s program memory. Instead, you can use for loops. The benefit of using a for loop is that you can determine how many times the code inside the loop will repeat. To see how a for loop works, enter the following code as a new sketch: Project 2 - Repeating with for Loops int d = 100; void setup() { pinMode(2, OUTPUT); pinMode(3, OUTPUT); pinMode(4, OUTPUT); pinMode(5, OUTPUT); pinMode(6, OUTPUT); } void loop() { First Steps 47 for ( int a = 2; a < 7 ; a++ ) { digitalWrite(a, HIGH); delay(d); digitalWrite(a, LOW); delay(d); } } .................................................................................................................................................................. The for loop will repeat the code within th...
Post a Comment
Read more
Project #3: Demonstrating PWM Now let’s try this with our circuit from Project 2. Enter the following sketch into the IDE and upload it to the Arduino: Project 3 - Demonstrating PWM int d = 5; void setup() { pinMode(3, OUTPUT); // LED control pin is 3, a PWM capable pin } void loop() { for ( int a = 0 ; a < 256 ; a++ ) { analogWrite(3, a); delay(d); } for ( int a = 255 ; a >= 0 ; a-- ) { analogWrite(3, a); delay(d); } delay(200); } .................................................................................................................................................................. The LED on digital pin 3 will exhibit a “breathing effect” as the duty cycle increases and decreases. In other words, the LED will turn on, increasing in brightness until fully lit, and then reverse. Experiment with the sketch and circuit. For example, make five LEDs breathe at once, or have them do so sequentially.
Post a Comment
Read more