@nkiit : Engineering is FUN

Cellphones in relationships : A survival guide

2011-07-20T21:31:00.000+05:30

So if you're in a relationship and you plan to buy a phone or have just bought one,
and it turns out to be an Android or iPhone, here are a few tips to prevent life from becoming
living hell

1. NEVER install WhatsApp
WhatsApp is probably the worst thing to happen to couples. Sure, you can message all the time for very little cost, but few are aware of the minuscule bomb planted into the app. Your other half can not only know if the message has been delivered like normal texts, but also if you have read it or if you started typing a reply and forgot all about them.

Yes, it can get ugly, can't it ?

2. NEVER share your location
Sharing your location means your other half will know exactly where you are and how much time you should take to pick them up. Yes, they will know much time you SHOULD take, instead of how much time you might take. Goodbye to all those little diversions for snacks or for saying quick hellos to friends.

Not a very pleasant thought.

3. NEVER get an Unlimited Data Plan
Getting an Unlimited Data Plan means you'll be connected pretty much 24x7. The horror of it ! So if you want some time for yourself or if you don't want to do something with your significant other, you'll have to dodge : phone calls, sms, WhatsApp, chat,location and any and all other services that you foolishly signed up for on their suggestion (read pestering)

And you thought you lived in a free country

4. NEVER use Foursquare
So managed to get out from a boring outing by lying ? Foursquare is your worst enemy. Sure, you can check into someplace to become the Mayor of that place, but you are going to get hell back at home. A pretty sad Mayor you would be.

5. NEVER get the same handset
NEVER EVER. They will make sure you have hell. How ?

If they approve of the idea, you will be embarrassed to hell listening to them rant on acting all cute and mushy and making you go "Leave my damned phone out of this".

Or better still if they DON'T like you getting the same handset, they'll make sure you give it to your younger sibling and get a new one within six months. Or face consequences.

Enjoy.

6. NEVER even get the same OS
If your criminal partner (partner-in-crime has gotten too mushy, and this term seems more appropriate) has a phone running Froyo, get one running Eclair, Gingerbread or Honeycomb. Anything other than Froyo.
In fact, get an iPhone. That way, you won't have to deal with their tech problems, share or approve of their enthusiasm for apps or be responsible for teaching them stuff. Or be responsible for sharing your cool new app with them. Because come on, even you like to be the only one to have an awesomely cool app sometimes, isn't it ?

I could probably go on, but I'd rather not for the sake of keeping it amusing and not-boring till the end.

And yeah. You have been warned. Take heed. Serious heed.

GRE.Check.

2011-04-19T09:40:00.000+05:30

Declarations and disclaimers :

1. This is not advice. I haven't put in any,so if you opened this looking for advice, you are going to be disappointed.

2. You and you alone are responsible for whatever you may find or learn or lose on reading this. I claim no responsibility or liability for anything. I do not even guarantee the accuracy of what I have written here.

3. I am done with my GRE, so I can write this with a little more detachment than those of you readers who are yet to give it.

4. Lastly, this is more of a debriefing than a narrative. Just saying.

<----->

A few things I have to say :

1. A big thank you to all my friends. For constantly wishing me luck. For not betting in front of me. For not pressurizing me. All of it made me work harder than I might otherwise have.

2. Thank you Bhumil Haria for giving the exam a week before me and providing a frame of reference.

3. Thank you everyone for the betting round on twitter. I have never ever opened Twitter to see 28 mentions in a span of 4 hours. Thank you for believing in me.

4. Thank you Tanvi Nabar for the chat outside Marwah house :)
Tanooj, not you. You don't ask someone what they are thinking right outside the exam center WHEN they are outside the exam center. You have to save it for later :P

<----->

A few things I saw at Marwah house :

1. Marwah house is a desolate place. Don't reach too early.

2. They make you check your pockets twice yourself before letting you in. Maybe they are afraid more of bio terrorism and anthrax powder more than people copying.

3. They have people to keep on staring at you via CCTV throughout the exam. "Uncle Sam is watching" is totally right. I don't know how much of perverts they are, but there's lots of scope there. Also, if we were to stare at a CCTV feed, we would be called jobless. They call it their job.

4. They provide ear muffs of the kind you find in shooting ranges. Pretty slick

5. They ask you to keep your food out in the open in the waiting area if you mean to have it in the break. I don't know if they have a bite from it,but its very possible. There should be an physical kind of MD5 checksum to check for tampering.

<------->

A few thoughts :

I did not prepare much. 3 weeks, and not even a dedicated three weeks. I don't know if classes helped, and I don't mean to find out. The one thing I am sure of is, I wouldn't have been able to perform better at any other time. Because it takes calm nerves to succeed where I think I screwed up.

I won't be so presumptuous as to generalise, but I find that the GRE confirmed one belief :
"You can only be prepared upto a certain extent. After that, you've got to be ready."

Disclosure :
My score is 1440. V 640. Q 800.
I had decent vocabulary and composition skills even without the GRE, so that might have helped. They just might have. Now you cannot blame me for incomplete disclosure.

Phototime

2011-03-30T20:22:00.000+05:30

Code is alright, but I have always been looking for opportunities to write small scripts, little things to automate life. Now, when I have the opportunity, I was only too glad to indulge myself.

I have been maintaining a photo-log since a few days, and that means a lot of photos everyday. The least I hope to gain out of this exercise is to know how my life progressed over a year.

So I figured I would have to name them consistently with their date and time as the file names.

What would let me do this ? Either have the camera's processor run the code (very far-fetched, true, but it might be a possibility) or have a script on my computer to do the same.

So I chose this opportunity to write a small Python script to rename all photos in a folder in such a fashion.

What it exactly does is :

Supply the path to a photo folder as a command line argument, something like :

python phototime.py /path/to/your/photos

and the rest is taken care of.

I've uploaded the project to a Github repository. You can download it from here.

Please leave back feedback if its useful or if it sucked. Remarks and suggestions for modifications are most welcome.

Design and Innovation Workshop, MIT ML

2011-03-29T01:57:00.000+05:30

This is the third and final article of the series I had planned.

This is just a placeholder until I get to it. A little patience :)

Innovation

2011-03-29T01:55:00.003+05:30

This is the second part of three-article blog post I had planned to cover what I learnt at the MIT Media Labs Design and Innovation workshop at COEP,Pune in January 2011.

   Y.oot noitavonni s
   e a
   s, this is counted

Caught your attention ? Good. Simply put, Innovation is a different way of doing things, finding a new way out. Why is this necessary ? An old saying summarizes this very nicely : If you keep on doing the same things, taking the same actions and thinking the same thoughts, you are going to get the same results that you've been getting.

I wouldn't be exaggerating if I said innovation is what has kept the world going. Innovation is what keeps on saving the world from grave problems. Innovation is what keeps on pushing man to strive harder and think smarter for "just a little bit more", "just a little better". Innovation is what open new paths, spurs new ideas. Innovation, for many, is what earns people their bread.

If you are wondering if innovation is *really* important to you.
It is important if you are an entrepreneur trying to enter a market.
It is important if you are an academician trying to make a discovery.
It is important if you are an investor, because an innovation is what is going to multiply your money a lot more than a "safe bet"
It is *also* important if you are a *consumer*, because innovation is what makes things simpler,cheaper and convenient for you.

So now that I've suitable stressed on the importance and need for innovation, I will leave you go through the presentation below about *how* to innovate. Prof. Ramesh Raskar is a part of the Camera Culture Group at MIT Media Labs, and I was lucky enough to have him explain his presentation below over web conference. Here's the presentation :

It would be presumptuous to have a "last word" after something as great as Dr. Raskar's presentation, but I do it solely to wrap things up.

Change triggers innovation. Innovation triggers change.

Innovation,whether out of necessity or genius, has equal impact. Whatever be your motivations, go out there and innovate.

Design

2011-03-14T01:44:00.001+05:30

Take a pool of car parts.
- Visualizing how the parts fit,work well,and look good is design.
- Putting them all together is engineering.
- Modifying the parts to make the car cheaper and faster is innovation.

Most of us when working on our projects always end up concentrating only on "engineering", and neglect the other two aspects.And it is those very aspects of product design we neglect that end up "screwing up" everything,as we call it.

Also,as always, I must talk point-wise.I blame engineering for this condition.

1. Design lets you have a broad idea of how to go about things, before actually doing them.
It can give you an idea of what difficulties you could encounter, or how things might be moved
around to give different or better results.

2. A good design is vital in making a product look good and sell well. If you don't design your product well, it is just going
to look like a lot of things stuffed into a box,for no apparent rhyme or reason.And face it,a stuffed box isn't what anyone is going to pay for.
Design helps differentiate your product from the others, and design is what will determine its appeal to your audience.

3. Design is important for documentation and business purposes. The idea you have when you make a product might not be apparent to someone else,
so it always helps to have the design handy when you want to transfer your idea to someone else. And it is always easier to find someone to fund you
when you have a design or a plan to show instead of the verbal "Its so simple, I can do it !! "

So what exactly do I mean by a design ?
It can be anything from a sketch,block diagram, flow chart, user interface,product appearance or anything that counts as a diagram. How come ?
Because a design is an aid to visualisation and conceptualisation, not a document to be turned it.If it expresses your idea,it works.

A design is an explanation of your idea.If you cannot explain an idea, the idea cannot live.
So the next time you work on any project of yours, make sure you have a design ready.

P.S. : Yes, that's correct. I like one word titles and point-wise discussions.

<-------------------->

I know, I know. These long gaps are becoming a bad habit, and must go.

This is a short piece on "Design" I wrote inspired from what I learnt at the MIT ML Design and Innovation Workshop. This is the first one in the series of at least three posts (I hope). Do leave your comments.

Write

2010-10-06T10:08:00.001+05:30

Write.

Yes. That's right. Write.
Write a diary. Or on pieces of paper,if you think "diary" is too feminine.
Or a blog if you are tech savvy. Or a note if you spend all your time on Facebook.
Write down your thoughts. Ideas. Incidents. Interactions.

Why ?

1. You never know when the next big idea to change the world might strike you. You don't want to lose that.

2. Incidents teach. Recollecting the what and why and what could have been of incidents makes you wiser.

3. What you learnt could help many others. If all those authors hadn't written those textbooks,management books and novels,you wouldn't have been as intelligent as you are. Its only fair to contribute yourself. Don't be selfish. Share.

4. It is one of the strongest forms of expression. Of your personality,opinions,hopes and aspirations."Freedom of expression" is not a fundamental right without a reason.

5. We are engineers-to-be. Documentation is a virtue. You may forget what you may have done,and how. So write it down now,when you remember. If you still aren't convinced, think of a world without those setup guides, manuals and FAQ pages. Yes, that counts as writing too.

6. Writing is NOT showing off, as some people might say. If you can write, you have a gift and you are a fool if you let others stop you from using it.

Okay, I have done enough writing for now..Its time you began !

P.S. If you are good enough, you can get paid too. And famous. Enough incentive ?

P.P.S Writing assignments doesn't count

[This is the article I submitted for the V.J.T.I. newsletter in October 2010]

The Circle Story

2010-09-16T23:53:00.000+05:30

      It all began with a line. Yes, a stupid line. Not that the line was really stupid, people just thought it to be so. Why, one might ask.

      For one,the line was remarkably straight. And quite tall. It needed very little space. But there were a few problems. It lived in a not-so-straight world. It stood out. Awkwardly. People pointed at it, they laughed at it. The line felt left out and embarrassed, but it was much too gentle to say anything. Maybe I am an odd-ball and my friends are too decent to tell me that, it reasoned. Maybe they are scared of being poked, it thought. It stood awkward,confused and alone in the middle of the crowd.

    One day, it decided to change. Now all this wasn't sudden,mind you. Its friends always said that it should turn to a more amiable, more friendly, less poky shape. Maybe they mean well, it reasoned. Maybe I should give it a shot. But what should it become ? It thought and thought, and asked and reasoned. Such a difficult decision. It is difficult enough to decide to change, but to decide what to change to.....

    A circle !!! Yes, that was it !! A circle was so round, so jolly, so amiable. It got around so easily, it got on so well with everyone, and no one was ever afraid of it being poked around. Yes, a circle it had to be.

   It took a great deal of bending and twisting to get there.It wasn't exactly easy, especially when it don't know what's wrong in the first place, and where it was supposed to stop. But it went along all the same..it cared a lot about being accepted. And then it was done. It became a circle. A decent one for what was once a straight line. It decided to go find out what its friends thought.

Everyone was delighted when they saw the circle the first time...What a splendid change in our friend,they thought. They rolled it around, they bounced off it, they even tossed it in the air and watched it bounce.They had a lot of fun with it in the beginning,but as with all new things, they got tired of it. The "new" circle,after its brief flirtation with popularity and fame, started feeling left out all again.

    It wasn't easy being a circle either,it found. It found that there was a lot of emptiness in there,where there was once nothing. And what was more scary was that it could see that emptiness all the time. It was frighteningly difficult to stop rolling, and it always felt like it would tip over at any time.

   It missed the time when it was a line. A straight line. But it was bent. Incorrigibly, irreparably bent. If only there were a way to go back. To go back...

-------

Just a random musing. All coincidences with existing lines and circles and other shapes are strictly out of the author's ignorance.

To Do

2010-04-03T23:26:00.000+05:30

Here's a small to-do list that won't be that easy to tick off :

1. Explore: What you do other than your academics is what will set you apart from the rest.

Intern. Take up interesting projects. Engage in social service. Explore your options. Familiarize yourself with all trades. Mastering one is the norm.

2. Diversify: Your branch of engineering is all you HAVE to do. It’s not all that you SHOULD do.

Broaden your horizons. Don't just engineer. Innovate. Manage. The more the faces to the diamond, the higher it’s value.

3. Design: No one wants to see oily gears or messed up circuits. The design and interface are what make products sell. Spend time on user interface design. A lot of stuff works well, but very little of that looks good while doing it.

4. Network: Find like minded people. Find the ones with the wacky ideas, and the ones with clear concepts too.

Helping people helps you. Look outside college too. There's a whole wide world waiting out there. It’s that world you have to conquer, so better know your allies and competition too.

5. Speak Up: No matter what someone tells you, you've got to ensure people know what you're all about. Speaking up is important, not only to make sure you're taken seriously but also to ensure that you get the right opportunities.

Have you begun yet ?

<--------------------------------------------------------------->

This was a small piece I wrote for my college newsletter, V.J News.

You can view the complete online edition here : http://dla.vjti.info/vjnews.html

Change

2010-03-01T19:06:00.000+05:30

Yeah, I know I haven't posted in a while. But this is not a revival. This is just a random post. Maybe there will me more soon.

Today's random thing I am going to talk about : Change.

Wikipedia defines change as : The process of becoming different. Aptly put.

So, going by the Wikipedia stub, I could talk about Calculus (mathematical rate of change), or Biology (metamorphosis), but I will talk about no such thing, partly because they aren't interesting blog topics and partly because I am ill equipped to discuss them anyhow.

So, I am driving at social change. Again, Wikipedia talks about social change as :

change in social structure, relationships, yada yada yada. I don't think this blog post is discussing that, but I'll find out by the time I finish this post.

What makes me talk about social change is the (almost) complete lack of thought on this issue. Who thinks of change ? Why think of change ? Chalta hai. Jugaad karo and be done with it. After all, India is a jugaad country..we Indians are famous for "making things work".

Well, that is taking a completely wrong meaning of "jugaad". But jugaad later.Change.

We take change as a corrective measure; something to be done to rectify something which happened. But that means we sink to apathy as long as things aren't "that bad". Why don't we view change as a means of getting something better than we have ? We take vacations as a change from work; we change jobs as a change from stagnation. Do we ever change our light bulbs because they are not energy efficient ? Do we do anything about apathetic public bodies or sub standard services ? No. Even if we see it affecting others around us. Not unless it affects us directly.

Elders tell us we think of changing so many things because we are "hot blooded and young", and we take their word for it and "calm down". Why ? Why don't we try ? Hasn't someone said that we would never know how well we can do unless we tried ? Marcus Aurelius said don't think why things are the way they are. Fair enough. But why don't we think instead on how we can remedy or totally eradicate those elements ?

A lot of people think society needs to change. Social structure needs to change. That's where thinking stops. Few want to change things because they can. Very few think what it needs to be changed to and how it is to be done. Even fewer go ahead and actually do it.

Sigh. Why ??

Why is not where we should stop. The solution is where we should begin. Change is what we should bring in. And no, we should not stop. Nowhere. At nothing.

The topic might be random, but this article isn't. I did not blabber for the heck of it. So spare me the sarcasm and skepticism.

A Techno gone by...

2009-11-08T12:54:00.001+05:30

I am in my Third Semester now, with term already over and semester exams scheduled to begin tomorrow.
Work for Technovanza, the college technical fest, has started a while ago, but is yet to pick up speed..
The study leave, as always, continues to be conducive to the creative cells, with every conceivable wacky pointless pursuit being pursued.
I wait for the Techno ahead of me, and I remember some sweet old times of Techno past.

I remember...

Looking forward for work to begin all throughout the exams, and feeling all pumped up the day the exams get over, all ready to do something cool for Techno.

Wearing the Techno t-shirt every third day in the vacation, and not at all during Techno, all to impress the visitors.

Leaving early for college in the morning throughout the winter break, coming back home for a nap in the noon and leaving for college again in the evening only to stay the night in college, and the irritation with which Mom used to ask, "Are you even coming back home tonight ?"

Running around doing everything with nothing happening, and finally those truly sweet few moments of pride when stuff finally works.

Going to "down" sugar-cane juice after getting bored with the work at hand

Getting all those "Gujju" home-made dabbas when spending the night at college, especially the "chakli", and having more than half of it eaten by others. And some people complaining right after eating those about my "Gujjuness" in bringing so many dabbas.

Roaming the college at 2 in the night without being questioned, and exalting in the calmness of the Quad from the third floor at night,and everything else for that matter.

Running away after a window opens when a friend is snapping pictures and being quite pleased about it.

The "Curse of the Blank Notepad" haunting me whenever I had to prepare a formal document related to a project. What's on your mind is NEVER what you can put on that file. What you can put on that file never crosses your mind.

Sweet December and January, with lazy sleepy mornings, the after-effects of the previous night spent listening to heavy metal while trying to figure out how to make the project work.

Feeling really happy when someone finally agreed to sponsor something, and arguing over who gets to go and collect the cheque, compared to the strong reluctance to go and visit the companies for the first time.

Asking every day of January whether lectures happened when you were out to a meeting,and then laughing immediately afterwards,saying you wouldn't have gone anyway.

The three days of Techno passing by ever so quickly.

At the end of it all, ruing the fact that I couldn't see everything because of the event I participated in, and how I got so few food coupons as compared to others, or how I could have possibly missed the supposedly "cute" reporter that came in half an hour ago.Also, its always funny that the professors who actually taught me always arrived when I was on lunch break.There went my chances of impressing them.

The "Box fight" and the demolition that took place immediately after Techno was over.

Going to the stage to receive the "Best Exhibit" award because the senior team members weren't there in the Quad.

Culture and arts are all fine and dandy, but the last night of Techno is reserved for all who cared to make it happen and all those who cared enough to stay back to tribal dance their hearts out. Ahh..what a dance ...

The Techno dinner with the awesome chocolate cake and the special (and more tasty) Jain food, especially for Jains like me.

I remember the last day of Techno being one of the best days ever.

I remember waiting impatiently for the days of the next Techno to come near.

I now have one more Techno ahead of me, and sweet memories behind...

Life has been good.

Keyboard + LCD Interfacing with ATMEGA16

2009-09-02T20:58:00.005+05:30

It has been two months and more since we planned to interface a Computer Keyboard, a Mobile Phone LCD and a memory card together to make a sort of a minimal standalone computer system.
The process has been long, with major and minor problems keeping on cropping up,stalling work and almost making us give up more than once.

However, today we crossed one more milestone...We have now interfaced the Keyboard and a 16*2 Character LCD simultaneously. That means we have now achieved 60% of what we set out to do.

I have already put up blog posts on Keyboard Interfacing and LCD Interfacing seperately, but making them together proved to be more of a battle than we expected. It wasn't as easy as just meshing together code from both the examples and making it run. There were a lot of small hardware issues and configurations which kept on coming up, but the most annoying problem was that if the connectors to the LCD aren't perfect, it would firmly refuse to even start up or start throwing curses in Chinese !!

Also, Keyboard Interfacing was only the beginning, as we had only obtained raw data from the keyboard and that needed to be mapped with its corresponding key. Here's a rough idea of what all needed to be done :

1. Obtain the raw data from the keyboard and decipher the key which was actually pressed. This was done by including two arrays, one for printing out Upper Case and the other for Lower Case characters.

2. The delay between keypresses needed to be set up properly to avoid a single keypress being detected as multiple key presses.

3. Pressing of Caps Lock and special characters etc needed to be dealt with separately to avoid erroneous/unwanted output and to implement changing of case, backspace,newline etc.

Ok, this could go on, but here's what this code can do in short :

1. Print key-presses on the LCD (obviously).
2. Detection of Caps-Lock and printing of Upper case and Lower case characters accordingly.
3. Newline feed on pressing Return
4. Erasing of characters on pressing backspace.
5. Clearing of screen on pressing F5

Special characters can be included as well with minor additions, but I'll leave that for later ;)

Here's an introductory video :

Here's the code.Click here to download.

<----------------------------------------------------------------------------------------->

Acknowledgements : Aniket Taati has been in this all along. I don't know what I would have done without him testing out the code I wrote initially ;) He's also responsible for adding a lot of the fancy features that make this project really useful. Many thanks to Rohit Pawar and Rajesh for setting up the hardware :D

Geeky Dreams

2009-08-17T17:24:00.008+05:30

It was siesta time yesterday and I was tossing around uncomfortably trying to think of something to dream about...And the fact that I had a lot to do other than trying to think of something to dream and that I wasn't doing any of it wasn't helping much either...

Then, like that rushing flood of relief which comes unexplained, it stuck me..SO simple..And so began my dream...Oh and you might want to forgive the tense used from now on, because the dream has not been forgotten..It still remains...

1. I dream of a time when everyone shall search for the same keywords AND get the same results.Implying that I dream of a time when I shall not have to Google search for my friends and family.

2. I dream of a time when everyone "gets" Xkcd.com ... I am tired of laughing alone most of time, or laughing with three to four friends at max.

3. I dream of a time when everyone USES all the online accounts they registered for.

4. I dream of a time when everyone learns How to Ask Questions the Smart Way (via @Sengupta)

5. I dream of a time when I won't have to deny 10 application requests and report them as spam on Facebook everyday. I also dream of a time when unknown people don't add me or at least have the courtesy to introduce themselves when they do.

6. I dream of a time when everyone checks their email regularly AND replies to them. Oh, and websites too.

7. I dream of a time when everyone checks who their replies go to when they press the reply button.

8. I dream of a time when everyone know that Google does not understand sentences, only words and what SEO means.

9. I dream of a time when people understand Facebook is a SOCIAL NETWORKING WEBSITE, not a psychiatrist or a quiz book.

7. I wish people paid more attention to serial numbers and what they read in general.

10. I dream of a time when everyone attributes the content they post, and CORRECTLY.

11. I dream that someday I won't have to empty my spam everyday in fear of having 600 spam mail lying there at the end of a month.

12. I dream that people would realise without me telling specifically that this article is in fact a wishlist, not a dream.

P.S. There's more to come right here, its just that I can't remember the entire dream all at once. ;)

P.P.S : Many apologies to the all-seeing a-lot-knowing one for my oversight-in-haste.One of my dreams would have been shattered by my own folly ! Fixed now ! :)

Dont You Facebook Quiz Me or ...

2009-07-28T23:59:00.004+05:30

Its been quite a while since Facebook introduced quizzes on its network to make some money. Fair enough. Its been quite a while since I had to tolerate my friends taking all sorts of weird quizzes, like "What kind of a vampire are you ?" (which was quite subtle compared to some others I have seen). Since Facebook was a good tool, I waited. Its been quite a while since they introduced those privacy features wherein I could block those stupid quizzes. Not very nice, considering I had to block each one day every time I logged in, but I did it. I tolerated the results of some of the stupidest,most pointless and the most irritating quizzes my friends took. I laughed at some results, jeered at the others and simply ignored the rest. Life's cool.

Then today I decided to see how stupid these quizzes could really get.

Facebook quizzes are the worst thing to happen ever.

The quiz I took was seemingly innocent for that matter. It invited me to find out "WHAT TYPE OF AN ENGINEER ARE YOU ?? " Well, I said, it can't be that stupid. So I began.

1st Question : My favourite subject. I answered IEEE 101. Fair enough. Expected question.

That's it. The END. Finis !! Khatam !! Khallas !! That was the end of any relevancy which existed in the quiz as well any patience I had left in me.

2nd Question : What kind of a car do you drive ? Bloody idiot, I don't drive !! (Not an option !!)

3rd Question : What country would you like to work in ? Losers, what's that got to do with what kind of an engineer I am !!

4th Question : What are the most important characteristics of an engineer ? Looks,Character,Smarts,Strength ? Duh !! I could never get it right !! I always thought the answer was laziness !!

5th Question : How many languages do you speak ? And the options included 1.5 and 2.5 !! Dumb asses !!

6th Question : Who is your pick of these sports ? Ooooo !! So smart !! You thought I would answer it correctly so that you would find out what type of engineer I am, huh ? GET LOST !!

7th Question : ON A SCALE OF ONE TO FIVE HOW IMPORTANT IS ENGINEERING TO YOU ? Its not important at all to me. I am just doing it because I don't wanna sit at home all day and help out Mom with daily chores. BRAINLESS VEGETABLE OF A QUIZ MAKER !!

Apart from how frustrating, pointless and irrelevant these questions are, the sad part is that millions of people take these stupid quizzes everyday !! I know people who only play quizzes on Facebook .. Its fun they say... Yeah, its fun alright if you call a dentist poking your eye to see if you need root canal treatment fun...Get a life, guys !!

Another thing I noticed was that apart from the 1st question, the other 6 questions would have made perfect sense in a market survey of some sort. I am not weaving conspiracy theories here, but it just might be possible that they ARE actually market survey questions that some unscrupulous developer is trying to push in.

These quizzes waste your time asking stupid questions, they waste your friends' time if you invite them and still waste some more time even if they block them. I am not being harsh, just practical. Not everyone wants to see how many and which stupid quizzes you have taken. If you want to take them, fine...Go ahead...But don't publish them in your feeds...No one wants to login to his Facebook homepage early in the morning to wake up to read "Find out at what age you will lose your hair".

And think twice before you invite ME to take a quiz !!

My kindest regards to all of you reading this. Its nothing personal. I just hate these stupid quizzes, that's all.

Interfacing a PS/2 keyboard to the ATMEGA16

2009-07-22T08:03:00.019+05:30

There are a lot of devices which would be great if we could use them to communicate with a micro-controller and a keyboard is one of them. Adding a keyboard interface opens up a whole world of varying your input to the MCU and controlling it.

A lot many tutorials about this are already available on the internet, but I found that patching ready made code to your MCU is most often problematic. Its best to understand the protocol and write code yourself.

THE PS/2 PROTOCOL :

This is how a male PS/2 connector (on the keyboard) looks like :

6-pin Mini-DIN (PS/2) Male Connector:
1 - Data
2 - Not Implemented
3 - Ground
4 - Vcc (+5V)
5 - Clock
6 - Not Implemented

Communication :

Each key press on the keyboard corresponds to a fixed hex code which is communicated by the keyboard controller to the MCU. This code is known as the scan code. This is followed by a "break code", which indicates that the key was released and consists of two "words". The first "word" is the same for all keys (generally F0), and the second "word" is generally the scan code repeated again.

Now let's deal with only communication from the keyboard to the MCU.

The data format is as below :

1 start bit
8 data bits, least significant bit first
1 parity bit (odd parity)
1 stop bit (always 1)

One word therefore consists of 11 bits, and three words make a package. One package corresponds to one key press.

Timing :

The data and clock lines are open-collector. They are always high in the idle state. The keyboard pulls the clock line low and generates a clock signal to begin sending data on the data line, when a key is pressed. Note that the keyboard won't send any data if the clock line has been held low by the micro-controller, even if a key is pressed.

The timing diagram for communication is on the left.

The clock line which is normally high is pulled low by the keyboard to begin transmission.
One clock pulse consists of a high level for half a clock cycle followed by a low level for the remaining half. Data is loaded when the clock line is high and therefore must be read when the clock line changes from high to low i.e. on the falling edge of the clock.

Timing is absolutely critical and wrong timing will lead to totally wrong or even no data.
The SCK line (used if communicating via SPI) should have a frequency of about 10 -16.7 kHz. Since we shall be using the interrupt method, we need not bother with the clock frequencies.

The Interface : Data acquisition

Data acquisition can be done in different ways, including SPI , or by continuously polling the data and clock lines to see when they go low etc. However, shall be using the interrupt method here.

The clock signal generated by the keyboard is fed to the INT2 line of the ATMEGA16. The reason for selecting INT2 is that it is an edge triggered interrupt and can be used to detect a rising and falling edge asynchronously i.e. independent of the MCU clock. The data line is sampled at every interrupt trigger and the needed bits are stored and shifted to obtain the scan code.Since we already know the data packet format, we can safely afford to neglect the remaining bits. Here, we shall not be reading the break codes. However, they may be used if special functionality is needed.

Code :
Keyboard Code
This code is very basic and will help you obtain the key scan codes. You can further add the look-up tables for these scan codes to identify the keys pressed. You could also try out key combinations and implement extra functions, password features etc.

Issues :
Reliability issue : The above code works just fine. One scan code can be detected additionally as well. However, if code to read the two scan codes that follow is added, all the data i.e. all three words get messed up. Reason yet to be detected and fixed.

References and additional reading :

1. Science Prog website
2. ComputerEngineering.org
3. Interrupt based Code

Images courtesy computerengineering.org

P.S : Code will be improved and added soon. Keep visiting !! :D

For You

2009-07-21T22:37:00.001+05:30

Here are a couple of poems I wrote :

Eyes dark as the black of the night
With a hidden glint like a thundering streak of light
A graciously beautiful guileless face
With hair curling over like tickly waves

A nimble spirit that cannot be bound
With feet firmly rooted to ground
Intricately crafted yet amazingly simple
Like the torrentous tempest within the gentle ripple

Innocent mischief runs deep in your voice
Your talk a carnival of colourful exuberant noise
Sweet,unpredictable,inexplicable,unexplaining
Like the time it first starts raining

A gentle soul,a golden heart
Of the world, but a world apart
I don't know what life has in store beyond the bend
But I am truly glad to have you as a friend.

<---------------------------------------------------------------------------------------->

The innocent waves curling at the shore
Bring to mind that sprightly hair
Aphrodite's beauty proclaimed by all folklore
Is but an allusion to your visage,so fair
Your cheeks rosy like an apple
Who wouldn't want to bite,
Your smile divine,your grace so simple
Would make a blind man see broad daylight
A voice so melodious,one can never have enough
A heart that infatuates the toughest of the tough
A gem of a person
A geniune friend
Straight from heaven
You are godsend

But so much time has passed,
Beauty,since I saw you last
All too often rises an urge above all the noise
An urge to hear your sweet,heart-warming voice
A desire to hear you talk
And a wish for you to never stop
I pray to God
I pray to see you soon
And make it so that I have you always,
Just like I have the moon

<---------------------------------------------------------------------------------------->

My Leh Trip : To Heaven and Back

2009-07-14T19:55:00.021+05:30

Awesome ! Amazing ! Superb ! Brilliant ! Pristine ! Beautiful !

These are definitely needed before I even begin to describe the places in the Ladakh region of Kashmir. All of it is beautiful, and I mean not only the places but also the roads and rivers and valleys and snow covered mountains and everything in and around them.

They are ideal for a getaway from the rat-race that is city life. Not only are they unique in their beauty, you will be gasping with awe every time you see a mountain or a river, no matter how many times you have already seen them.

Here are some of the places I visited :

Srinagar : A bustling city, the gardens are a must watch. They are really beautiful and very well maintained. Staying in the house boats is a novel experience, even if they are half moored on land and don't move about in the lake.

Sonmarg : A truly beautiful place. Lots of greenery,snow. Good place for adventure sports. The Thajwas glacier is quite nearby from here. A nice tricky place to climb up a snow mountain without much equipment ;) If you are going somewhere and are passing through Sonmarg, it is best to pass Sonmarg before noon, as the heavy motor vehicles are let out at noon and they therefore hog the road.

The route from Sonmarg to Kargil has awesome sights, and nothing less than pictures can do full justice to it. On this road, the journey is literally more beautiful than the destination.

Drass : A town en route to Kargil. Reportedly the coldest inhabited place in the world. Non-vegetarian food is the major diet here.

Kargil : A small town which gained popularity after the 1999 Kargil war, there isn't much to watch here except a museum which has war relics as well as a 5 Lakh note (currency, I don't know :S ). It gets pretty cold here during the night. There is a memorial dedicated to Operation Vijay, which won us the Kargil War, some distance before Kargil.Almost all the mountains on which battles were fought can be seen from here.

On the Kargil - Alchi route comes the famous Maitreya Buddha statue, that of the Buddha to come.

Also on the way is the famous Llamayuru monastery.

The way from Kargil to Alchi is mainly rocky and barren mountains, but those mountains emanate a strange kind of beauty. They are beautiful in a special way,more beautiful than any kind of other moutains you will see.

Uley : Uley is a small village some way before Alchi,and is actually just a resort in the lap of nature. It is truly natural, with cottages surrounded by apricot and apple trees and overlooking the river. Its very peaceful and serene over there, away from everything. A perfect getaway. My previous poetry perfectly describes Uley. Oh, and those of you wanting to tweet from there about how great it is, there is no mobile network coverage there ;)

Alchi monastery is another famous monastery.

On the way from Alchi to Leh are quite a few interesting sights :

1. Magnetic hill : Keep you car on the white paint on the road, and the hill automatically pulls the car toward itself. Unbelivable, eh ? Try it, it works.

2. Pathar Sahib : This is the place where a demon threw a large rock on a meditating Guru Gobind Singh. The stone failed to do any harm on the Guru and a partial impression of Guru Gobind Singh can be found on that rock.

3. Hall of Fame Museum : All of the Indian army's exploits in the mountainous north can be found here, including the adventures in Siachen and the Ladakh ranges. Commendable work and impressive show.

Leh : Leh is quite a big town, with a large part of the population there engaged in the booming tourism industry there. Agriculture is another important occupation here.The Ladakhi song and dance is truly light and beautiful.Don't miss it.

Leh is the center for most tourist activities, and people generally visit the Pangong Lake, Nubra Valley, Tsomoriri and Tsokar from here. Things worth seeing in Leh are the Leh Palace and the Shanti Stupa. Leh is a popular destination for cycling, motor-cycling,rafting and para-gliding. Likir and Thiksey are the famous monasteries en route Hemis.

Likir Monastery

Hemis : Hemis is a village a little ahead of Leh. It is famous for its monastery. It is the only monastery which holds its annual festival in the spring, when there is no snow, unlike all others which conduct them in winter, and therefore cannot be witnessed by most tourists. This festival is immensely colorful and attracts a lot of foreign tourists as well as locals. This festival consists of a complete village fair along with cultural and religious programs in the monastery. This festival generally happens for 2 days in a year in the beginning of July. I was lucky to catch it on the 2nd and 3rd of July.

Lake Pangong : A 5 hour drive from Leh, this lake is the highest inland lake in the world, and is shared with China. This is a real gorgeous work of art by God and shines with all the shades of blue and green when the sun shines on it. Truly worth watching.

On the way to Pangong lake is Chang-La Pass, the 2nd highest pass in the world (17586 Ft). It is generally snow covered and windy. A cool place to be ;) It is difficult to stay there for more than 20 minutes due to breathing problems caused by the lack of oxygen at such a high altitude.

Nubra Valley : It is a beautiful valley at a 5 hour drive from Leh. On the way is Khardung-La, the highest motorable road in the world (18380 Ft).

The Hundur and Deskit villages are rest spots in Nubra valley, with camel safaris close by. The strange thing about this is that there are silver sand dunes right next to the river ! Apparently the J & K Tourism Department thinks that this has good potential ;) The only lodgings here are tents. If you can find a camp by a river, you will get a real good chance of experiencing nature at its very best.

Sarchu : Sarchu is a beautiful place almost midway between Leh and Manali. Baralacha, Tanglangla and Nakeela are the lofty passes on the way. Also on the way are the Chandra Taal and Deepak Tal,lakes from where the Chandra and Bagha rivers originate. Sarchu is surrounded on all sides by mountains. There are camps on the flat land between the mountains which truly make you feel small :D The wind whispering in your ears all evening is an added joy. At night temperatures go down to 2-3 degrees so be prepared to face the cold.All said and done, Sarchu is a place worth visiting.

Its a pity Sarchu lies where it does.The route from Leh to Manali is the worst I have ever seen in my life. There are no pucca roads.In certain stretches visibility is a serious problem due to the dust the vehicles kick up. There is a 5 minute flat stretch for which the road literally disappears..All one sees is tyre tracks going everywhere and no kuccha or pucca road !! God help the inexperienced driver ! Also, there is no mobile network coverage once you leave Leh uptil Keylong. So if you are stuck, may other drivers help you !

All said and done, all of it makes you feel like you have come to a different world altogether. So if you get a chance, TAKE IT !! The beauty there is Leh-gendary !!

The Getaway

2009-07-03T12:08:00.003+05:30

I know of a getaway, away from it all
Far away from the noise, where few footsteps fall
Resting blissfully in nature's loving arms
Where we can give in to the life's simple charms

Where rises the sun early and bright
And the weather is always just about right
With early morning rain to wash its face
And clouds to line the sky like pearly white lace

With tress laden with apples,raw and sweet
And farms all around gleefully waving its golden wheat
With a gentle river to maintain the peace,
Overwhelm the troubled mind and bring it to ease

This place, it would break your heart to leave
This haven, where a year would seem but an eve
This getaway of mine, is no childish fancy
This portal to heaven, is beyond what you could ever fancy

MHT-CET 2009 Results

2009-06-14T12:37:00.010+05:30

The MHT-CET results are out today (actually yesterday night at around 1 am, because they always manage to mess up somehow,but they rectified the mess and made it unavailable again early in the morning at around 9am till 10 am).

Click here to view the result
Click here to view the top 100 students

Having already been through this phase and having not much interesting stuff to do, I decided to go through the results to have an estimate as to what juniors I might get at VJTI. Here are my observations :

1. Mumbai, Mumbai Suburban and Thane together have 55 or so toppers among the top hundred

2. A fair number of them are Gujjus. ( No implications, just an observation ;) )

3. The toppers from Agrawal Classes in HSC have yet again made it to the top in the MHT CET

4. The top-100 closed this time at 191 as opposed to 193 effectively last time.

5. The last rank given to a guy at 196 was 46 last time whereas it is 18 this time. This means that the density of students at the very top is less. This probably, not necessarily means that the density below (after and around 192/191) maybe be higher. However, I expect cut-offs to go down by at least 1 or 2 marks this time.

6. As last time, the number of people in the top 100 from the reserved category are less. This effectively means that more people from this category will get a better chance to get into the most desired institutes.

Finally, for those wanting to getting into or knowing about VJTI, let me tell you :

1. All the bad press VJTI got recently about losing autonomy is very biased and prejudiced, written by one and only one reporter. There were management concerns expressed, but I think this presentation here effectively puts them to rest.

2. VJTI does NOT have an AIEEE quota. UICT (now ICT) does have one, and it is possible to take admission there in the AIEEE quota without even participating in the CAPCAI rounds.

People who want to take admissions in these autonomous institutes generally prefer :

VJTI : Computers,IT, Electronics, Mechanical
ICT : Chemicals, Pharma
COEP : Computers, EXTC, Mechanical

Details for admission to Autonomous Institutes here
Last year's cut-offs for Autonomous Institutes (2008-2009) here

Cheers,

If any of you have any queries about admission to VJTI, please post a comment.. Would be glad to help out.

Hope to see some of you around in VJTI :)

SPI : Serial Peripheral Interface

2009-05-24T09:27:00.035+05:30

The serial peripheral interface provided in the ATMEGA16/32 allows a high-speed synchronous data communication channel with other devices.The relevant pins on the ATMEGA are :

1. MOSI : Master Out,Slave In :

Pin B,5

This line is used by the master to send out data to the slave.The Master always initiates any communication.

2. MISO : Master In,Slave Out :

Pin B,6

This line is used by the slave to send data to the master.

3. SCK : Serial Clock :

Pin B,7

This is the serial clock generator. Communication takes place only when the clock is working.The clock starts a cycle when the master initiates communication.

4. (~SS): Slave Select :
Pin B,4

The slave will respond only if the Slave Select line is pulled low.If not pulled low,the chip will not read data even if keeps on receiving clock pulses.The Master pulls the Slave select line high again at the end of the data transfer to synchronise the slave.

Connections :

Master ------------------------------------------> Slave

MOSI ------------------------------------------> MOSI

SCK ------------------------------------------> SCK

~SS -------------------------------------------> ~SS

MISO <------------------------------------------ MISO

Data Flow :

The SPI supports a full duplex operation, which means communication can take place both ways simultaneously, i.e. data can be sent on one line and received on another line simultaneously.

When two-way communication is desired, it is best to follow the following method.
1. Write Data to the SPDR (SPI Data Register)
2. Wait till the transmission is complete. You can do this either by polling a flag or by using interrupts.
3. Read the SPSR (SPI Status Register) and then the SPDR immediately after that, in that order, if you are using the polling method. Just reading the SPDR is enough if you are using the interrupt example.

This will prevent any accidental loss of data.

This can be done safely even with the slave, since the data which has been queued up in the SPDR will not be transmitted unless the Master initializes communication. However, iteration-based loops cannot be used in the case of the slave to send data, since it is unsure when the Master will initiate communication and so the data would keep on updating in the SPDR without being sent. It is thus advisable to use the interrupt method in case a transmission by the slave is desired.

Modes of Operation :

Click here to view the modes of operation

Control registers :

• Bit 7 – SPIE : SPI Interrupt Enable

This bit causes the SPI interrupt to be executed if SPIF bit in the SPSR Register is set and if
the global interrupt is enabled.

• Bit 6 – SPE : SPI Enable

1 ----> SPI Enabled
0 ----> SPI Disabled

• Bit 5 – DORD : Data Order

If DORD = 1 , the LSB of the data word is transmitted first.
If DORD = 0 , the MSB of the data word is transmitted first.

• Bit 4 – MSTR : Master/Slave Select

MSTR = 0 ----> Slave Mode
MSTR = 1 ----> Master Mode

If SS is configured as an input and is driven low while MSTR is set, MSTR will be cleared,
and SPIF in SPSR will become set. MSTR will then have to be set again manually to re-enable SPI Master mode.

• Bit 3 – CPOL : Clock Polarity

CPOL = 1 ----> SCK is high when idle
CPOL = 0 ----> SCK is low when idle

• Bit 2 – CPHA : Clock Phase

The settings of the Clock Phase bit (CPHA) determine if data is sampled on the leading (first) or
trailing (last) edge of SCK.

• Bits 1, 0 – SPR1, SPR0 : SPI Clock Rate Select 1 and 0
These control the SCK rate of the Master device and have no effect on the Slave. The relationship between SCK and the Oscillator Clock frequency (fosc) is shown in the following table:

Status Register :

• Bit 7 – SPIF : SPI Interrupt Flag

This flag is set when a serial transfer is complete. An interrupt is generated if SPIE in
SPCR is set and global interrupts are enabled. If ~SS is an input and is driven low when the SPI is in Master mode, this will also set the SPIF Flag. SPIF is cleared by hardware when executing the corresponding interrupt routine or it can be manually cleared by first reading the
SPI Status Register with SPIF set, then accessing the SPI Data Register (SPDR).

• Bit 6 – WCOL : Write COLlision Flag

The WCOL bit is set if the SPI Data Register (SPDR) is written during a data transfer. The
WCOL bit (and the SPIF bit) are cleared by first reading the SPI Status Register with WCOL set,
and then accessing the SPI Data Register.

• Bit 5..1 – Res : Reserved Bits

• Bit 0 – SPI2X : Double SPI Speed Bit
When this bit is written to one the SPI speed (SCK Frequency) will be doubled when the SPI
is in Master mode . This means that the minimum SCK period will be two CPU
clock periods, as opposed to the minimum of 4 in normal mode. When the SPI is configured as Slave, the SPI is only guaranteed to work at fosc/4 or lower.

The SPI interface on the ATmega16 is also used for program memory and EEPROM download-
ing or uploading.

Sample code:

Click here to view the sample code

The code to setup the slave is pretty simple and can be found in the ATMEGA16 Datasheet on Page No. 139

Resources :

1. ATMEGA16 Datasheet
2. Modes of Operation
3. Sample Code

A Parliament of another sort (more practical too)

2009-05-19T14:15:00.003+05:30

Disclaimer : Before you read on, be aware that these opinions are not my own but rather of a personality imagined up by a warped mind. I am not responsible for any emotional trauma or distress arising out of reading this article and I write this for the sole purpose of imaginative humour. You may however thank me if you find it enjoyable.

<--------------------------------------------------------------------------------------------->

There are 3 broad categories of people and each of these categories forms a parliamentary party :

1. The JOCKS (RULING PARTY) :

Also known as the cool ones, these guys currently run the affairs (literally and otherwise). They like to be called "playas" and would enjoy nothing more than chilling out with a beer at some groovy discotheque. They understand little of what each of the other parties ( geeks, nerds,gals etc.) are upto but they more than make up for it by their diplomacy.There is a continuous power struggle going on between members of the Ruling Party and the Third Front (Gals) as they each threaten to disrupt proceedings. The relationship between these two parties is bitter sweet, with each soliciting each other's support in times of crisis as well threatening to take off the legs of the chair in relatively peaceful times.

2.The Geeks (OPPOSITION) :

These are the intellectually superior class , but they often lack common sense. They are unable to attain success mainly because of their fanatical involvement in their own affairs or showing support/opposition to one another rather than gang up on the Ruling Party members. It has been well documented that most of the Opposition members have had "homely" ties with the Ruling Party members. The Opposition members perpetually endeavour to solicit the support of the Third Front, but results are generally disappointing because of their lack of diplomacy and the fact that they do not take out the Third Front leaders out to dinner as often as they would like.

3.The Gals (The Third Front) :

These are the game changers. One moment they support you, the other they don't. Members of the Third Front have been known to cause the downfall of many a great leader. They command respect from both the Ruling Party ( mainly because of their threats to withdraw support) as well as the Opposition ( which is forever pining for their support). Their moods fluctuate predict unpredictably, which is one of the sources of their power. That their egos must be satisfied is an undeniable fact. One known way of doing this is by granting them positions of power (no matter how frivolous they sound).

Besides these, there is an emerging party of the minorities ( the nerds, the misfits etc.) but we'll come to that some other time.

Note : The Third Front and The Ruling Party both claim to be the ruling party, the Ruling Party because they have a strong hold and the the Third Front because their support is absolutely essential for running a Government.

<--------------------------------------------------------------------------------------------->

P.S. This post has been possible because of an intellectually stimulating and highly amusing debate with a very good friend. A big Thank you :D !!

Linux Distros for Free : Mumbai

2009-04-25T11:12:00.022+05:30

Hello folks !!

Just today I woke up with this great idea of doing something good and something useful.
Well, I was thinking what it could be, when I suddenly tried a software which increased my Internet download speed exponentially ( 7kbps to 400kbps is exponential from me :D ). Then it struck me !!

I am going to try and spread Linux distros around me...
My major reasons for deciding to do so are :

1. Linux is a great open source alternative and the communities are active
2. Its not very popular among people I know and people around me
3. People who are interested can't get their hands on distros, since none of them except Ubuntu give out free CDs, and downloading or paying for them somehow doesn't appeal to a vast majority of us Indians... ;)

So, here's how I aim to do it :
1. Drop me an email or comment on this post with your emai id if you are interested in a Linux distro I mention below or any other (free) distro which you have in mind
2. I contact you
3. You provide me a blank CD and I burn the distro on it for you. Simple !!
4. Also, please do spread the stuff around, as this is what this initiative is about anyways.

AND BEFORE YOU ASK, I AM PLANNING TO DO IT FOR FREE !! (Unless you REALLY want to pay me for it :D )

Also, if you are interested in helping me with my initiative ( since I can't reach out to too many people alone), please contact me via email and we can work something out.I really need help from you people if this is to succeed, you know.

I REPEAT, I AM DOING THIS FOR FREE. ALL YOU HAVE TO DO IS DROP ME AN EMAIL OR COMMENT ON THIS POST, GET A BLANK CD ALONG, AND I'LL BURN THE DISTRO FOR YOU.

<---------------------------------------------------------------------------------------------->

I am in the process of adding distros, so please bear with me while the entire list comes up.

You can find a list of various popular distros and their comparisons here:

1. Linux Forums

2. Distro Watch

<---------------------------------------------------------------------------------------------->
DISCLAIMER :
You must realize that this is a free service meant to help you all, so please do not try to sue me. I am just trying to provide the software as is. I do not promote use of any of the above software. I am not responsible for damages/losses or any adverse effects resulting out of use of any of the distros provided. It may not be possible to respond to all requests, but I will try my best.

Way2SMS : Simply awesome !!

2009-04-24T10:27:00.005+05:30

I am quite freaky about my email and like to check into my mailbox every hour or so. Now, I do not have a Blackberry and my service provider does not provide me with an email notification service. So what I used to do was use GPRS to check my email, which was quite fussy, with me having to open my mobile browser,go to my email homepage etc.

Recently, I was searching for a convenient alternative when I came across "Way2SMS" which provides exactly what I was looking for : free SMS notifications as soon as new email arrives !! Awesome !!

How it works :
I sign up for a Way2SMS account, they ask me what user id I prefer ( its something like your_id@way2sms.com), fill up your number and some minor details and your account is ready !! Then you go to settings, and in the SMS tab and activate mail notifications. Simple !! Awesome !!

Now,all you have to do is forward a copy of your email ( from whichever email ID you use) to your way2sms id and you are done...Every time you get an email, you get notified on your cell phone.Plus, they also let you chat on your GTalk and Yahoo! ids from within their dashboard, pretty decent mp3 ringtones,an address book, quick SMS and Group SMS. Their SMS feature also beats SMSGupshup because they allow you to send SMS upto 110 characters and unlike SMSGupshup, all of my messages till now have neither been delayed or lost.

The only catch I found in Way2SMS was that they require you to activate your email notification setting every 7 days, otherwise it is automatically deactivated.I understand its a way to make sure users keep coming back and not forget about it, but I am sure they will be able to work out a better way.

Ok, to sum it up, here's what I loved about it :

Instant SMS updates (they claim 10 secs. and deliver too) on receiving email
Usable with any email service that lets you forward email,even official IDs
Customisable,in case you want to receive only specific updates
You can select what time and days you prefer to receive notifications
You can select to receive notifications only from your contacts
They do not serve ads at the end of email notifications (not yet,anyways)
You can notify recipients on their mobile when you send them email (!!!)
ITS ALL FREE !!

I hope they carry on the good work !! Kudos, guys !!

------------------------------------------------------------------------------------------------
Disclaimer : This is NOT a paid review. All views expressed here are my own.

Exernal Interrupts on the ATMEGA

2009-04-14T11:37:00.008+05:30

So, now you know how to use the ADC and the UART features present on the ATMEGA.The ATMEGA16/32 has one more feature of great importance to us : external interrupts.

Click here for a short summary on interrupts

Okay, now why are they of importance to us ? A lot of stuff generates signals in the form of voltages or voltage changes to indicate decided events. For example, a device might have one line which goes low for a few clock cycles and then high again to indicate that it has completed its task.We can therefore use this line as an external interrupt line to schedule further tasks.

The ATMEGA16/32 has 3 external interrupt lines : INTO,INT1 and INT2, on pins PD2,PD3 and PB2.

Interrupts on INT0 and INT1 can be

1. level-triggered(meaning that the interrupt is triggered when the signal goes low i.e. 0V for some time

OR

2. edge-triggered(meaning that the interrupt is triggered when the signal changes from high to low or low to high)

====> INT2 can only be used as an edge-triggered interrupt.

Setting up the interrupts :: Control Registers

MCUCR : MCU Control Register

Bits 3,2,1,0 are the ones which are of importance to us.

Bits 3,2 are used for sensing an external interrupt on line INT1.
Bits 1,0 are used for sensing an external interrupt on line INT0.

The table for setting up these bits is as follows :

The table for INT0 is similar to the one above.

It is to be noted that if an edge triggered interrupt is selected, the edge (change) must last for at least one cycle for it to be detected. Similarly, if a low level triggered interrupt is selected, the low signal level must be held till the instruction being executed currently by the MCU is completed.

MCUCSR : MCU Control and Status Register

Bit 6 is the only one of importance here, and controls the INT2 line.

If this bit is set to 1, a rising edge generates an interrupt and if it is set to 0, a falling edge generates an interrupt.
The pulses here also must be longer than one clock cycle.

Also, the ISC2 bit must be set following a specific method,since an interrupt can occur even while changing the ISC2 bit.

The procedure is something like this :

1.Disable INT2 by clearing its Interrupt Enable bit in the GICR Register.
2.The ISC2 bit can be changed.
3.The INT2 Interrupt Flag should be cleared by writing a logical one to its Interrupt Flag bit (INTF2) in the GIFR Register before the interrupt is re-enabled.

GICR : General Interrupt Control Register

Bit 7,6,5 enable the INT1, INT0 and INT2 lines respectively if set to one.

GIFR : General Interrupt Flag Register

Bit 7,6,5 manage the status of the Interrupt requests. The flag is set for each of these when the respective line is triggered, and cleared when the corresponding interrupt service routine is executed.Alternatively, we can clear the flags manually by writing it to 1.

Click here to view sample code on interrupts

<--------------------------------------------------------------------------------------------->
Resources :

1. ATMEGA 16 Datasheet
2. Introduction to interrupts
3. Sample Code

The images of the register configurations have been taken from the ATMEGA16 Datasheet.

ADC on the ATMEGA

2009-03-28T16:47:00.026+05:30

Ok, I know its been long and I am rusty with my writing, so here's a quickie.

ADC stands for Analog to Digital Converter. What do we need it for ? Well a lot of sensors that are used in Electronics(and Robotics) give output voltages in the form of potential differences. Doesn't make sense ? Simply speaking, a sensor will give out its readings in the form of voltages. So what do we do with it ?? Well, we convert it to a number which will help us determine the actual implications of that reading. We fix a maximum reading as the reference number (255 in our case,since we will be ignoring the last 2 bits) and calculate the corresponding value of our reading on the new scale.

So, moving on, the ADC feature is available on PORTA of the ATMEGA16/32.

Features :

1. The reference (maximum) value can be taken from the AREF pin or an internal reference level of 2.56V is provided which can be accessed by the software. The AVCC may also be used as AREF by simply decoupling it(connecting to ground through a capacitor).

2. 10-bit is available. This means that you can distinguish between two readings which have a difference of (Reference Value/2¹⁰) . This means that the max value is broken up into 2¹⁰-1⁼1023 parts and if you have a reference of say 5V, you can distinguish between readings 4.88mV apart (yeah, that's right !!)

3. The ADC can be used in free running mode(which means it will keep on converting continuously) or single conversion mode.

4. An interrupt may be generated once a conversion is complete, so that the MCU need not keep on checking for completion of conversion.

5. There is a ADC Noise Cancelling mode, which allows the user to switch off the other digital circuitry which might affect the conversion.

6. Since the result is 10 bit, the result is stored in 2 registers : ADCH and ADCL. If the ADLAR bit is not set, the result is right aligned. In that case, the 2 MSBs of the result are the 2 LSBs of the ADCH register and the remaining 8 LSBs of the result are in the ADCL. In this case, it is necessary to read the ADCL first and the ADCH second, only then will the ADC registers be updated with the next result.

7. Accuracy is best between 50 and 200 Khz clock frequency. Running at 16 Mhz,we select the prescaler as 128, which gives a clock frequency of 8/128, which is 125 Khz.

Code :

Now, we set up the registers.

Next, we write the functions to initialise ADC and call a conversion.

Resources :

1. ATMEGA16 Datasheet Pages 204 - 221

2. ADC Tutorial on AVRFreaks

3. Sample code

4. Registers