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Meet the Arduino

5. Parts of an Arduino

Let's take a look on the main parts of the board:

Arduino Uno microcontroller and its parts [12]  

Reset Button

Three engineers are riding in a car.

One is a mechanical engineer, one is an electrical engineer, and one is a computer engineer.

The car breaks down and coasts to the side of the road.

"Hang on," says the mechanical engineer. "The problem is probably the engine, let me have a look at it and I'll have us on the road again in no time."

"Wait," says the electrical engineer. "The way it just stopped like that, I think it's the electrical system. Let me have a look and I'll get us going again in a minute or two."

"Hold on," says the computer engineer. "Why don't we all just get out of the car and get in again, and then see if it starts?"

The reset button restarts the program currently uploaded on the Arduino.


USB port

The USB port takes a standard USB A-B cable. It serves to connect the Arduino to a computer in order to program the board. It can also power the Arduino if we are not using the power connector.


Power connector

The connector connects the board to a power source, which can be either from an AC/DC adapter or a DC battery.

Built-In LEDs

The LEDs marked TX and RX show whether the Arduino is sending
or receiving data. The on-board LED marked L is connected to Pin 13.The Power LED indicates that the Arduino is getting power when you turn it on.

Digital Input/Output

These pins are for digital input and output. They are used to either sense the physical world (input) or control lights, sounds, or motors (output).

Analog Input

These pins take sensor readings in a range of values (analog), rather than just sensing whether something is just on or off (digital). We will explain more about this later in the course.

Microcontroller

This is an ATmega328P chip. This is the “brains” of the Arduino: it interprets both the inputs/outputs and the programming code uploaded onto the Arduino.

Power pins

Next to the analog pins, there are some pins marked Power. They can be used to power circuits on a breadboard.