Sunday, March 30, 2008

Some data sheets related to 8085

A couple of days ago I posted an article on Microprocessor Programming on this blog. There I wrote about the Intel 8085 microprocessor and posted a link to its data-sheet. However, later I found some of the other data sheets related to Intel 8085 microprocessor. They consist of mostly those ICs which I had in my curriculum and used in projects. Here are the set of the data sheets that I have. I have uploaded them for you all.

Intel 8085A 8 bit Microprocessor for Military purposes
Intel 8085AH 8 bit HMOS Microprocessor for general usages
Intel 8155 2048 bits Static MOS RAM with IO Ports and Timer
Intel 8255A Programmable Peripheral Interface
Intel 8279 Programmable Keyboard or Display Interface

Looking at the original data sheets help a lot. You get valuable information from them. Remember that a data sheet is the document that is supposed to provide a complete overview of the IC as well as explain its capabilities and structure from the users point of view.

Well, that is all that I could find in my hard disk. Even I am surprised to see them still there. If I find some more helpful stuff, I will post it on this blog only. If you require some other data sheets, just post a comment.

Friday, March 28, 2008

Microprocessor Programming

I have been interested in Microprocessor programming ever since I had it in my curriculum back in 2005 for my B.Sc. Computer Science final year. We had the Intel 8085 in our syllabus and coding on it was real fun. In fact it was a revelation for me to know how exactly were the instructions executed by a processor. It gave me an in depth view of the internal hardware level working of a computer.

Recently I am getting a lot of questions about the simulators and help files for microprocessor programming, not only for 8085, but also for Z80, 68K and 8086. So here is a collection of stuff that I have collected and book-marked over the years on this topic.

Intel 8085

Most of the coding that I did for Intel 8085 was either on paper or on the simulator. The simulator which I used was GNUSim8085. It was an excellent simulator and allowed me to debug and set breakpoints in my code and the ability to trace the program while checking the register values and the memory contents after each instruction execution. I have uploaded for all of you, the program along with a very helpful guide that I downloaded from the Internet. Download GNUSim8085.

The two books that I followed for 8085 were authored by B.Ram and Gaonkar. The Gaonkar book is very popular with students across India and the first book by B.Ram has got some very good codes written. I also recommend the original data sheet of 8085 which is of great help.

Motorola 68000

Recently one of my fellow MSPs asked for help on microprocessor programming on the legendary Motorola 68000, also fondly known as the 68K. I never did any real programming on this one. I have never even seen a kit also. The coding that I did was all on a simulator that I found on the Internet. You can have a look at the 68000 simulator homepage and download the simulator for Windows platform from there.

I also happened to stumble upon this great book called Motorola M68000 Family Programmer’s Reference Manual from Motorola which was of great help in understanding the architecture of 68K. It was a great help to programming too. In fact it was due to this book that I was actually able to help out one of my friends about 68K.

Lastly ...

I guess the above information was useful to you. I wrote this post keeping in mind all the things that I would have liked to know and download when I had started coding with these microprocessors. If you feel like saying a Thank You or need some additional information, post a comment here.

Monday, March 24, 2008

Get back some free space after installing Vista SP1

When we install SP1, the installer keeps copies of the older versions of files it is replacing. This is done just in case the user wants to roll-back to the  original Vista, without SP1. However if you are satisfied with the machine after installation of SP1 (like its running for a couple of weeks without any glitches), then its safe to assume that you will never want to uninstall SP1. So you can delete these unnecessary set of files and get back some free space.

Thankfully this feature is already provided with SP1 installer, so no need to delve deep into the file system or download third party tools. Just open the command prompt and run vsp1cln.exe. It takes little time to execute.

Saturday, March 22, 2008

Another Great article on Apple

Being in India, I have only heard of Apple as a company. I have never used a Mac in my life, but I from what I gather, Apple has become an urban legend. I have tried my hands at iPod and liked it a lot. The UI was great as well as the integration level with iTunes.

Then I got hold of the book: "iCon", a biography of Steve Jobs ... "the greatest second act in the history of business". Upon reading it, I have become an admirer of Apple and Jobs. Needless to say, whenever I get a new article with Apple's name on it, I try to give it a read. Here is something that I found today : How Apple Got Everything Right By Doing Everything Wrong. Despite its bit quirky title, it was very interesting take on Apple's policy and strategies. How they are going against the open-source and other popular beliefs and practices and still emerging as a successful company. I recommend it to anybody interested in the urban legend of a company called Apple.

Wednesday, March 19, 2008

IE 8 standard support

Currently, the Internet is abundant with articles, posts, debates (and flamings) about the standards support of IE8. The IE8 beta 1 which was released last week added more fuel to the fire. A lot of developers are concerned about it and a flurry of debates is livening up the scene.

Most of the stuff that we usually encounter on this topic can be classified into:

  1. Highly technical : For the set of hardcore developers and geeks only. Most of it does not make sense to outsiders.

  2. Technical : Like the ACID test. I do not know how many people totally understand it (I don't), but the basic idea is easy to grasp with pictures and all (and that is why the popularity).

  3. Hype, Criticism, and Flaming : IE Lovers Vs IE Bashers ... the usual age old battle.

However, today I encountered a totally different type of article which explains the whole standards thing from a different perspective, which apart from making a lot of sense is quite a good read. Very oddly titled Martian Headsets, the article compares the standards thing with a odd example. In spite of the lightweight and funny attitude, the author, Joel Spolsky, manages to explain the thing rather clearly and I got a clear idea of what was the main problem with the IE8.

Friday, March 14, 2008

My first session on .NET

Yesterday I delivered my first session on .NET as a Microsoft Student Partner (MSP). The session was held in the Sun Lab of Dept. of CSE in University Science College, Rajabazar. The topic was "Introduction to .NET". Around 30-40 pupils from our department attended the session along with a couple of members of faculty.

Initially I was feeling a bit tensed about having to give a public talk, but it all vanished as soon as I started interacting with the audience. The discussion was aimed at giving a good overview of .NET and demonstrate its features. The initial discussion about the features was a bit boring I guess, judging from the scarcity of response from audience. But it all livened up as soon as I began to show the Demo Applications. The audience began to ask a lot of questions and I did my best to give satisfactory answers.

The whole session went on for about one and half hours with lots of questions from the audience. The session came to an end with Prof. Sanjit Kr. Setua (SKS) announcing that our Department has subscribed to the MSDN Academic Alliance. This will allow all the students to use the entire suite of Microsoft softwares (except Office) for non commercial purposes both on Campus, as well as their home PCs.


Here are a couple of pictures of the session :


I have created a web based file sharing account for the MS_Club's use. There I will put up all the files associated with the MS Club of CU. The URL is : The club members will be able to access all the files. To prevent unauthorized access, there is a password protection.