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Free Software and Open Hardware talk on Chelakara

Published on: February 20, 2009

Brief report on the talk conducted at Government Polytechnique college, Chelakara

Yesterday (19-02-2009) Krishnan Unni and I went to conduct a talk on Free Software, Python Programming and Open Hardware. These talk’s were conducted as the request from students of poly technique.

I and unni reached the college almost at 10.00 AM. There was a small inaugural session. After that we were asked to start the talk . The morning session was on Free Software Philosophy, GNU/Linux installation steps and general GNU/Linux doubts. this was handled by Unni.

All the students were eagerly hearing the talk. There was a very good response from the  students. And the important thing is that all the students were very interactive. Questions were coming from all sides on general GNU/Linux tools, virus removal methods, installing games, accessing internet….. This session had an end at 12.30 PM.

The afternoon session was split into two, the python programming and the other was Open hardware. Python Programming was handled by unni. There was a small programming contest on python. He also showed how to develop software’s using python.

My topic was Open Hardware. Actually what I had in mind was introducing what is open hardware, common electronic designing tools and programming the AVR microcontrollers using GNU/Linux. But everything changed after seeing their syllabus.These guys had to  study about ATmega128 and also about ARM processors. I was shocked seeing it. Even the calicut university Electronics Engineering syllabus didn’t have these latest topics. I introduced about open hardware. But programming the AVR microcontrollers was not that much nice. There was a parallel port failure and the other fact was that the students knew how to program all these . What I showed was LED blinking. But they had studied blinking LED’s in their 6th semester itself. Anyway I could have made it more fun if  I knew about the syllabus by adding some superb videos like Big Buck Bunny :(

Now I am in a shame to say that I am learning Electronics engineering because a lower course like the diploma had a lot more to study than engineering course…. these students were more practical.

Anyway the response form the students were fantastic. Thanks to Yamini Madam and all the computer science students of chelakara.

Drawdio Hacked !!

Published on: February 09, 2009

One of the cool device designed by Jay Silver of MIT is DRAWDIO.  Drawdio is a pencil that can make sound. Don’t be surprised. In short drawdio is a pencil that lets you draw music.

See this page

I decided to build that pencil. I collected documents from Ladyada’s Drawdio page. The TLC 551 IC was not available in the electronics market in THRISSUR. Actually TLC 551 is a low voltage version of LM 555. So I decided to replace TLC 551 with LM 555.

After building the circuit, I fed it with 5V supply. Since it was LM 555 I fed 5V. If it were TLC 551 we can use a AAA battery to power the circuit.

But the transistor started to heat up. I think that the transistor (amplifier) circuit was designed to be powered from AAA battery. So the 5V might have made it to heat up.

There comes my hack. It’s not actually a hack. I found that we can easily replace the amplifier circuit and the speaker with a buzzer. I have redrawn the circuit with the buzzer. You can download the modified circuit.



This circuit succeeded for a 5V powered LM 555 circuit. But I don’t think it will work if you use a AAA battery to power the circuit and also replacing the LM 555 with TLC 551. If the circuit is powered by a AAA battery, the buzzer wont produce sound that is much audible. so in that case you will have to use the amplifier and the speaker circuit.

These are the two snapshots that has been modified from

Use this snaps together with the circuit diagram to build the DRAWDIO. See these snaps. These are test run done by me on the breadboard.


Project Euler for hackers

Published on: February 07, 2009

Want to be superb in mathemetics and programming?

See this Project Euler

Try to solve the problems over here

I think in this way hacking skill can be increased….

Cool Avatars on my blog

Published on: February 06, 2009

An avatar is a computer user’s representation of himself/herself or alter ego, whether in the form of a three-dimensional model used in computer games, a two-dimensional icon (picture) used on Internet forums and other communities, or a text construct found on early systems such as MUDs. It is an “object” representing the embodiment of the user. The term “avatar” can also refer to the personality connected with the screen name{.mw-redirect}, or handle, of an Internet user. — Wikipedia

I was in search of some cool avatars. It was at that time I came with Splitbrain‘s Monster ID. Using his package you can create cool moster avatars…

From his page I got the wordpress plugin for Monster ID maintained by Scott. You can download the plugin from his page and have cool avatars come up when some one comments your blog. Now cool monster’s come on my comments my blog. The monsters now created are based on email address. Even monsters can be created using ip address etc….

The avatars wont come as soon as you comment. You will have to just refresh the page.

This was the avatar that I got from the comments posted by me

My first blog post in my own blog

Published on: February 05, 2009


It’s long I have blogged. Actually this is my first post in this year !

Special thanks to God almighty, my parents, my brother, and all my friends and relatives…

Now onwards this blog will be updated in every 2 or 3 days. Please keep in touch…

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