First I must emphasize that there are a number of different sites dedicated to producing and documenting homebrew CPUs and computers. Most of them much better than this blog.
So here is a link for the reader who might want to educate him/herself on this topic:
The question immediately arises: Why does anyone need another homebrew project?
I have noticed that I tend to have similar attributes/background to those working on these crazy projects.
I have been always fascinated with electronics, computers and programming (in this particular order). As a kid (at the age of something like from 10 to 12) I had been designing basic electronic circuits. I had not had much knowledge of electronics of course.
Once in a while I could meet my uncle who being an electrical engineer guided me. Unfortunately he lived in a different country (still does) and therefore we could meet like once for an afternoon for every two years.
I was just rather experimenting with basic circuits, combined them and wanted to be able to build more complex and useful electronic components/devices. At that time I totally believed in myself and I though that I could build almost anything even not having any proper backgrounds, nor education on the topic.
Not just I was a true believer but I happened to be quite convincing...
In grammar school I was designing small electronic "games" similar to those LCD handhelds, which enjoyed quite popularity in the 1980s. Of course my electrical devices were nothing but crap compared to the products available on the market in those days.
In fact, I was only able to build just one working prototype (very basic with some blinking light bulbs and two buttons).
Despite this fact, or because of it I produced catalogues of my devices (with product code, game design, etc.) to come. I showed this brochure in school to those who were interested in owning a handheld device, but their parents were not able to afford to buy one.
One afternoon a family of fours visited our house. Up to this point they had never been to our place. The guy was a classmate of mine.
My father welcomed them. They happened to come actually buy a product, a handheld device. Funny is not it?
They actually believed that I could produce such handheld devices and sell them. I was very embarrassed and just watching from the background. Father not knowing almost anything of my hobby and my promises, informed them kindly about where those devices are available for sale.
Soon after they left with disappointments on their faces.
I was something like 13, when I was given a C-64. From that point on, I gave up designing electronics and devoted my time to computers almost entirely.
This turned out to be very useful as far as the tidiness of my room was concerned. With the C-64 I did not produce such mess, so my family was happier then ever before.
Once in the mid 1980s I had the opportunity to visit my uncle abroad. I spent like two weeks with them in the summer. They were very kind and welcoming, organizing all kind of outdoor programs/activities for me, but really all I longed for was just sitting in my uncle's working room and design electronic stuff with him.
In fact, this very summer I designed my first computer-like device. Which as far as I can recall was just based on some counter. It was supposed to be able to give a control signal each step when counting from zero to upwards.
Needless to say it never materialized. Actually it could not have worked since I just simply did not have the technical skills to design such thing.
Then I turned again away from electronics in favour of computing.
Later in college, I have had some kind of courses dedicated to electronics, but at that time I just simply did not want to learn electronics. All I was interested in programming and software development. To be honest, I actually could acquire almost no knowledge out of those courses. It is a shame...
After being a software developer for many years, an Oracle consultant to be more precise, I turned to electronics again.
It happened exactly on 5th of October, 2011. Steve Jobs died on this day. Although I have never been an Apple fan, never paid particular attention to Apple products I was touched by hearing the sad news. It is difficult to tell what exactly I felt. It was a kind of emptiness. It was as I had lost a close relative. I guess that with Steve a whole era has died. The golden era of computing of the seventies and early eighties.
I started to study Apple and its history. I came across with the other Steve, Steve Wozniak and his story, which gave me tremendous inspiration. I decided that I would study electronics. I searched for old books on this subject. I started reading them and refreshing my knowledge. Then I soon realized that analogue electronics is a huge and very difficult subject indeed. So I decided to turn my attention to digital electronics, which looked simpler and more promising at least in terms of how a cicruit can be designed and built. Learning by doing is an easy and fun way. That is why I decided that I will actually learn digital electronics by designing and building simple devices.
I have then decided that the device should be a CPU. Obviously one cannot design/produce a CPU alone meeting today's standards and performance, but this is not really my goal. My goal is:
1. As already stated to learn digital electronics by doing it. That is to design and build a CPU, a very simple one, one of the simplest possible, which is still complex enough to be called a CPU. But more on this later.
2. To better understand computer architectures.
3. And last but not least having fun.
This is how this blog was born.