Start With ArduinoThe Indian Way - Low Cost and Quick

Kinds of Arduino Boards

There are Four kind of boards

● With USB port -Arduino UNO, Arduino MEGA● With Serial Port - Arduino Severino (Lowest Cost)● Small Size - Arduino Nano, Mini,Lilypad● With some thing extra - Arduino BT, Arduino Ethernet

Which One Do You Need

Depends upon your need.

Which one do We use and why?

We use Arduino Severino. Why?

● It is low cost. Costs less than Rs 600/- for complete board and PCB at just Rs 50/-

● Provide serial interface for use with GSM or GPS boards.

● Has all DIP parts, rework or changes are easy.

And why we do not use others

● USB based boards and blank PCBs are expensive.● Double sided boards can not be easily reworked.● If boot loader gets corrupted (and it often does), it is difficult

to program further.● Connecting GSM or GPS or Standalone blue tooth boards

are difficult (if not impossible)

And how to program it

We use low cost USB ASP programmer which can be connected to any lap top on USB port.

With this programmer you do not even need boot loader and any blank IC can work.

USB ASP programmers are also available for less than Rs 600/-

So what is the total cost for starting

Arduino Severino Clone - Rs 599/-USB ASP Programmer - Rs 599/-Serial port cable - Rs 75/-USB Cable - Rs 75/-12V / 300 mAmps power supply - 150/-

Total cost - Rs 1498/-

Install driver for USB ASP

Download USB ASP driver from http://www.fischl.de/usbasp/

Connect USB ASP, when Windows ask for driver, point to the location where you have stored unzipped drivers.

On Device Manager, you can check LibUSB device.

(Linux and MAC does not need driver and skip this step)

Find Location of preference.txt file

Download Arduino from arduino.ccInstall on your PC with Windows, Linux or MACUnzip and start.Open Arduino and click on preference in menu

specify programming methodOpen preference.txt file.Search for text 'upload'

if you find a line like this upload.using=bootloader

change it to usbasp if you will be using USBASP for programming upload.using=usbasp

or leave it as it is if you will be using bootloader for programming

What is upload or programming

When we write program in C and click on UPLOAD the arduino converts C program to machine code and generate a hex file.

This hex file will be transferred to micro controller.

there are two methods - one is via serial port (this needs micro controller already burnt with bootloader program)

second is using a separate programmer like USBASP. This does not need a micro controller. Please also note that when you get a arduino board, this comes with pre-loaded bootloader. However after you program with USBASP, bootloader is over written.

Write first program

Connect Hardware with USB Port

PC + Arduino Severino + USBASP + 12V Power Supply

If using Windows, check that USBLib is visible in Device Manager. (If you do not know what is device manager, search it yourself)

make sure that preference.txt file has upload.using=usbasp

Connect hardware with RS232 port

PC with serial port + Arduino Sevnerino + 12V Power Supply

You need to have ATMEGA8 with bootloader

and preference file should have

upload.using=bootloader

Select Board, Verify and Then Upload

To select BoardTools | Boards | Arduino NG or Older w/ATMEGA8 To select com port (when using with bootloader)Tools | Serial Port | Select appropriate port number

To compile(verify the syntax)Sketch | Verify or Compile To download to the boardFile | Upload to I/O Board

After uploading is over LED will start blinking at 1 Hz rate ie half second on and half second off.

Some thing about bootloader

Bootloader is a program that allow more programs to be uploaded with using external hardware.At power on if bootloader is burnt into chip then program wait for few seconds for data from serial port,

if data is available in some defined format that this is stored in flash as program.

if nothing is coming from serial port then last uploaded program starts.

More details about bootloader are available herehttp://www.arduino.cc/en/Main/Bootloader

Modify The Program

You can change the time in parenthesis after delay and see the difference in blinking.The first time is time for LED ON and second is time for LED OFF

This LED will blink as per program

Understand pin numbers

IC has some physical pin numbers. ATMEGA8 in 28 pin package has 20 I/O lines and few pins for oscillator and power supply etc. Physical pins are usually required for making circuit and when probing using CRO or multimeter.

20 lines are given some names like PC6 where PC stand for Port C and 6 is the bit 6 of port c. During programming in C/Assembly we use PC6 and not the physical pin.

Arduino board has these 20 lines taken to a connector. These connector pins are marked 0 to 19. In Arduino software we refer to these pins ie 0 to 19 and not port pins or physical pins.

Understanding Pin Numbers

Some pins have dual purpose

For example Analog pin 0 is also digital pin 14.

Pin 0 is also Received data

Next few pages have more details and mapping of pin numbers ie physical - logical - arduino

Understand Pin Numbers

This board has 20 I/O pins marked on pins.all of them are I/O. Some have dual purpose.

Understanding Pin Numbers

All 20 pins can be access as general purpose I/O pinsSome pins have other functions as explained below

Pin Number Function

0 RXD

1 TXD

13 On board LED

9,10,11 PWM (Analog Outputs)

14,15,16,17,18,19 Analog Inputs 0 to 5

2,3 Interrupts 0 and 1

ATMEGA to Arduino Pin Mapping

ATMEGA has 28 physical pins. In data sheets they are referred as Port and a number like PC5In Arduino they are referred as numbers 0 to 19.Mapping of all three is as below

Summary

This document explain the first day of experiments with Arduino Board.

Total hardware cost of material used in less than Rs 1500/-

Not much can be done in this however this is a starting point.

Next addons could be relays, IR Sensors, Remote handset, Temperature sensors, Light Sensors. Color LEDs, Buzzers.

All this material will cost less than Rs 1000/-

About Open.Embedded

This is an initiative of group of professionals, students and hobbyists to share their knowledge among others using low cost open source software.

We think it criminal when students are taught 8085 and 8051 in college when world is moving forward and technology changes are happening every where in the world. Join us at facebook.com/open.embedded Buy low cost kits at stores.ebay.in/openembedded

Modification History

Aug 18,2011 - details about bootloader added