Getting Acquainted With Arduino

Many of you must be reading this after referring other websites but still I expect you to go through this "story" as if you are hearing it for the first time. Please be patient till then :). Also suggestions are welcome if you think something is not correct.

Arduino is a tool that allows you to make projects with simple coding that would else require a complex programming and circuitry. To start with imagine arduino as a box that has some inputs and some outputs. What arduino does is it fetches inputs, manipulates them and gives outputs according to the code that it has. Thats arduino in a nutshell. We will get into the details after checking out its various parts (I prefer using Arduino UNO but little things change with different models) :-

                                                                                      

1. USB Plug:- This port is used for uploading programs or commonly called "Sketches" on your Arduino. This can also be used for powering Arduino from your PC.

2. Digital I/O pins: Pin 2-13 as labelled in the picture are used for taking digital inputs(0s and 1s or to be practical 0 volts or 5 volts) and for giving digital outputs ( Though Arduino comes with a function to mimic analog outputs that is almost continuous voltages from 0 to 5 volts).

3.Reset Button:- As the name suggests this button when pressed forces the arduino board to restart itself resetting the program and memory content of variables (we'll discuss all about it :P).

4.Serial Programmer:- These pins allows arduino to "communicate" with your PC. For many basic applications you won't need them.

5.ATmega328 Microcontroller:- This is the "heart and brain" of the Arduino. All the operations, decisions and manipulations are done in this IC. It is a single package microprocessor with Memory for the program instructions and data in it along with other resources like input output memory blocks, timers etc. To conclude it is a tiny computer.

6.Analog in pins:- These pins are the most useful pins onboard on the Arduino because these help us to communicate with analog sensors that sense features of physical world( light, temperature , humidity etc.).

7. The Pins next to analog pins are the so called Power Pins. I will describe each one of them below:-

            a)Voltage in:-This pin can be used to supply voltages ranging from 7-12 volts (to be on the safer side and ensure that under no case you end up burning something) that is regulated to 5 volts and fed to the ATmega chip.

            b)Ground Pins:- These pins are connected to zero volt reference or the "Ground". Any voltage read by or returned by Arduino is with respect to these pins.

            c)5 Volt pin:- This pin is 5 volts above the ground pins. These oins can source upto       200 mA of current but it is better to be within 100 mA and not test the boards limits.

            d)3.3 volt pin:- This pin is 3.3 volt above the ground and is ideal for powering MOSFET based devices and lightning LEDs.

            e)The Reset Pin:- This pin resets the arduino board whenever it sees a high or 5 volt above the ground.

            f)The power port:- This can be used for powering the board with unregulated dc voltage of 7- 12 volts.(Again little less than its tolerance to be safe).