Microcontrollers

Yesterday we had Bejoy Sir's class on microcontrollers. It was this year's first class by Bejoy Sir. The entire morning session was spend on the theory part of microcontrollers.


First of all, we were told the difference between microprocessor and microcontroller. While microprocessor is for general purposes, microcontroller is used for a specific task. Microcontroller has a microprocessor as well as other parts to carry out the required task.


                  
The picture shown is of an Intel 8051 microcontroller. Source


Then, we discussed about polling and interrupt methods. In polling, the processor does one task and after finishing it goes to the next in a sequential manner. But in interrupt, the processor can be made to pause the execution of one task and do another task of higher priority by issuing an interrupt signal. When an interrupt occurs, the processor does the Interrupt Service Routine (ISR). Interrupts can be vectored or non-vectored. For vectored interrupts, the processor knows what is the location of the ISR that is to be executed. But for non-vectored interrupts, the ISR location has to be specified by the programmer. The processor comes back to the program that was being executed when the IRET instruction is encountered in the ISR.


Then, we discussed about serial and parallel communication. Simplex, half duplex and duplex were also mentioned. After the theory session, we did some practical work on the Arduino Duemilanove microcontroller.




                 




The picture shown is of an Arduino Duemilanove microcontroller. Source


The first program we got was to blink an LED which was really simple. Then, we did a program to operate an LED using a pushbutton switch. The program we did next was to blink an LED using a circuit involving an LDR. After that was done, we were shown an LCD display done using the Arduino microcontroller.

More of Octave programming

As fixed, we reached here at nine. We were asked to wait in the L3 lab. After waiting for some time, the EC guys thought of practising their lab experiments for the coming university exams. So, they asked and got permission from Mahesh Sir to do it.

When they were gone, the rest of us spend the time browsing the internet. It was noon when the EC guys were done with their lab. So, we had lunch. During the afternoon session, Mahesh sir gave us the history of free softwares,  the GNU project and GNU/Linux OS. We were also told that Richard Stallman(rms) was to visit our college during this month. Another thing we came to know was that the college intended to distribute the codes of the previous projects done here.

Then, we got to do an Octave program on Linear Regression. A bit of browsing gave us an idea about linear regression and soon the programming was done.

First Class of 2012

Today's class was to begin at nine in the morning. When we reached here, the task we got to do first in the morning was to install Octave package in all the systems in the L3 lab. After that was done, we were asked to do an Octave program to perform selection sort on the contents of a file. That was an easy job.

During the afternoon session, we had to compare the time taken by selection sort to perform on various number of inputs. We had to do one more thing. Form groups of two members each and do a presentation on any topic. We were to do this at three in the afternoon, which meant we had two hours to prepare.

My teammate was Vivek and the topic we selected was Apache helicopters and Hellfire missiles. The other presentations were about RedTacton, Magic Square and Facebook.

More TED videos

Here are a few TED videos I saw recently.

Gaming is not so bad after all

This was the TED video I saw today. It's about the good effects of gaming on the human brain.

Back to blogging

Haven't been around for a few days, two to be precise, and here I am, back to blogging. Spend the days watching movies, playing with friends, etc. I did watch a few TED videos. Here are two those.

The first one is this.

Here is the second one.

TED video for Christmas

This was the TED video I saw today.