29th : Embedded Systems - Day 1

Today , I decided to BEGIN my journey into the world of embedded systems.

The first step, as they say, is literature survey. I realised (after finishing the survey) how important it was to do some reading before raiding. Books are people in text form. People who worked passionately in a domain, experienced successes and failures at various levels. No doubt, there are many like that, but those who write books are a special kind. They want to 'share' their experiences with us. So that, we may build upon what they left.

I had this habit of slowing down my walk on the road whenever I see a bookshop. I am most hated for this habit by my close friends. While they want to do brisk window shopping, I would be walking dead slow near a pavement that showcases old books.

I have a collection of Readers Digest magazines from the 60s somewhere. The list goes on.

Of late, I began buying books that have anything to do with Embedded systems.

When I browsed through the collection, I realised that I have many that haven't been read at all. But, like friends, they were there, waiting for me , silently, unmindful of the dust they were gathering , all because of me......but ready to help when I was in need.

So, I rediscovered Labrosse's Embedded Systems Building Blocks , Vahid/Givargis's Embedded system design, Mazidi and Mazidi's The 8051 microcontroller and Embedded Systems , John Catsoulis's Designing Embedded Hardware, Steve Furber's ARM System on Chip Architecture and my more familiar friends Ray and Bhurchandi. I also had copies of Barry Brey & Sharma and Uffenbeck.

Glad to have so many helping hands, we all sat in a closed room with a cup of coffee. Mind you , with books, you can save on coffee too. Books dont drink coffee (unless you spill on them occassionally) do they ?

I fixed a time limit of an hour to identify the major issues that challenged me. First I wanted a definition of Embedded systems. I asked Labrosse first. "Bross, Embedded System kya hai ?" Because, you know , he had been designing Embedded systems for more than 17 years .

He said, "I can help you ,if you are already an embedded system programmer. I will provide ready to use modules. Do you know C ?"

I said yes...but (keep it secret) it was a weak yes. It was more like a C-- , if there was one !

"...and you must have a minimal knowledge of assembly language"

I nodded more in agreement than in confidence.

Now, I realised that I was talking to a man whose time I would be wasting unless I am on par with his requirements.

So, I have to plan for my C and assembly language skills, if I wanted to be an Embedded System Designer. Labrosse will be waiting for me until then.

He said something in passing which appealed to me. " I have designed many systems, and during that time , some pieces always keep coming back. I have concluded that 80+ percent code for an embedded product seems to be similar to the previous product. "

"like humans " I thought.

He continued thus.."I ALWAYS SEEM TO NEED TO READ ANALOG AND DISCRETE INPUTS, OUTPUT CONTROL SIGNALS ON ANALOG AND DISCRETE OUTPUTS, PROVIDE SOME FORM OF USER INTERFACE AND THUS, I NEED TO READ/SCAN KEYS ON A KEYBOARD AND PUT INFORMATION ON A DISPLAY DEVICE OF SOME SORT (7-SEGMENT NUMERIC AND/OR LCD MODULE). MOST EMBEDDED SYSTEMS SEEM TO HAVE AN ASYNCHRONOUS SERIAL PORT AND INTERFACING TO A LAPTOP SEEMS LIKE A NATURAL THING TO DO".

This was a very valuable piece of information. It was almost like picking already-made-parts and assembling a new-whole based on my idea. So, how much of programming do I need to know ? Only as much as to understand what has already been written in C or Assembly, modify it to suit my application. So, I only need to do a li'l bit of tinkering with the code. No need to start from scratch. "Brosseeeeeeeeee..you are my man"...I thought.

He also gave me a nice block diagram to show what he meant.

Needless to say, while I was talking to Labrosse, others were a bit restless. So, I shifted my attention to Vahidbhai. The Vahid-Givargis duo took over and said that if I wanted a comprehensive exposure to Embedded system design, they would give it to me. Something like an aerial view.They would take me from the first level of Programming, Logical/Digital Design, Computer Systems organisation to the next level of Introduction to Embedded Systems and MORE importantly, to the appliation areas of Embedded and Real time systems, Advanced Digital Design (synthesis) , VLSI/ASIC Design, Control Systems, Digital Signal Processing. WOW ...they sounded awesome two some. However, I realised that they would be only useful to some extent and would not help me when I am really toiling with the components in the lab.

I realised, I understood what they were talking only partly.

What is an embedded system ? I still needed an answer. However, I needed to get into the thick of action.

So, I concluded the meeting, realised that the coffee got cold ! I was so embedded in to the conversation, that I forgot to drink my coffee.

I remembered Labrosse's words (in blue above) and prepared myself to find out what was available in the market in terms of components.

I decided to take my next step as a learning task.

Take a sensor , read its signal into the computer in my lab.

So, off I go....

Have a nice day.....