The Novice Writer: Arduino Basics!

ARDUNIO BASICS

What is a Microcontroller?

A small computer on a single chip containing a processor, memory, and input/output, typically "embedded" inside some device that they control.

A microcontroller is often small and low cost.

What is Microprocessor?

A microprocessor is a computer processor which incorporates the functions of a computer's central processing unit (CPU) on a single integrated circuit (IC), or at most a few integrated circuits. The microprocessor is a multipurpose, clock driven, register based, programmable electronic device which accepts digital or binary data as input, processes it according to instructions stored in its memory, and provides results as output. Microprocessors contain both combinational logic and sequential digital logic. Microprocessors operate on numbers and symbols represented in the binary numeral system.

The difference between microcontroller and microprocessor:

Microprocessor	Microcontroller
Memory and I/O given externally	Memory and I/O present internally
Circuit is large	Circuit is small
Cannot be used in contact systems	Can be used in compact systems
COST Increases	COST Decreases
POWER CONSUMPTION HIGH due to large circuit	POWER CONSUMPTION LOW due to small circuit
They do not have power saving features	They have power saving features
OPERATION SLOWER due to externally operation as memory being external	OPERATION FASTER due to internal operation
LESS NUMBER OF REGISTRIES. Therefore memory based	MORE REGISTRY Programming is faster
Used in pc	Used in washing machines,mp3 players, etc

What is a Development Board?

• A printed circuit board designed to facilitate work with a particular microcontroller.

• Typical components include:

• power circuit

• programming interfaces

• basic input; usually buttons and LEDs and I/O pins.

The Arduino Microcontroller: Atmel ARV Atmega 328

Input and Output:

Each of the 14 digital pins on the Arduino Uno can be used as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhms.

In addition, some pins have specialized functions:

Serial: Pins 0 (RX) and 1 (TX). Used to receive (RX) and transmit (TX) TTL serial data. These pins are connected to the corresponding pins of the ATmega8U2 USB-to-TTL Serial chip.

External Interrupts: Pins 2 and 3. These pins can be configured to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details.

PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.

SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication using the SPI library.

LED: 13. There is a built-in LED connected to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it’s off.

The Uno has 6 analog inputs, labeled A0 through A5, each of which provides 10 bits of resolution (i.e. 1024 different values). By default, they measure from ground to 5 volts, though is it possible to change the upper end of their range using the AREF pin and the analogReference() function. Additionally, some pins have specialized functionality:

TWI: A4 or SDA pin and A5 or SCL pin. Support TWI communication using the Wire library.

There are a couple of other pins on the board:

AREF. A reference voltage for the analog inputs. Used with analogReference().

Reset. Bring this line LOW to reset the microcontroller. Typically used to add a reset button to shields which block the one on the board.

TECHNICAL SPECS:--

Microcontroller	ATmega328P
Operating Voltage	5V
Input Voltage (recommended)	7-12V
Input Voltage (limit)	6-20V
Digital I/O Pins	14 (of which 6 provide PWM output)
PWM Digital I/O Pins	6
Analog Input Pins	6
DC Current per I/O Pin	20 mA
DC Current for 3.3V Pin	50 mA
Flash Memory	32 KB (ATmega328P) of which 0.5 KB used by bootloader
SRAM	2 KB (ATmega328P)
EEPROM	1 KB (ATmega328P)
Clock Speed	16 MHz
Length	68.6 mm
Width	53.4 mm
Weight	25 g