Wednesday, October 28, 2020

Retro Computing.

Is retro computing something you just do for fun? Certainly, but not only!

The microcomputers of the 80s were open and easy to program, often in Basic, but also in assembly language. It was quite easy to create cartridges or expansion boards for them. Everyone remembers the Commodores, Atari, Apple, Sinclair, BBC etc etc...


In short, a time of great creative freedom. All this gradually disappeared with the hegemonic position of the PC(IBM) / Microsoft 'association'.


Is it possible to regain some freedom again in this digital world? Yes of course. By resuming and 
continuing the great road of creation abandoned in the early 90s. How? by taking up some good ideas from the time and developing them :


There were a lot of good ideas in the 80s. But, if we take the case of 8-bit machines, the MSX standard was a very good initiative since it allowed a good stadardization of the computers, while preserving a good freedom of design. This standard was originally initiated, among others, by Microsoft : 


To enter the MSX scene, It is obviously possible to equip yourself with some new MSX machines based on an FPGA, but I think that in the introduction, a machine created such as at the time would be a good starting point.


All this written, it remains to find an effective solution to launch into the realization of an MSX machine. Fortunately, Sergey Kiselev has recreated a great MSX computer motherboard called Omega :

My own Omega main board issue.

The Omega computer is not based on any computer that has existed but only on the MSX 2 standard. Therefore, it is necessary to obtain a whole set of obsolete components but still available on the Net.

It may take a little time to build this board but the months ahead should leave time for this task. In the end, it should look like this :

https://www.retrobrewcomputers.org

I am thinking of using my own keyboard version with this Omega.

A good introduction to the MSX standard with the Yamaha CX5M computer, recently published :


Of course there were some great 16/32-bit machines as well, Amiga, 520ST, but that's another story...



Monday, October 26, 2020

Retro keyboard.

Iin 2016, Wichit Sirichote created learning kits for different types of microprocessors, including the Z80 : 


This kind of kit is very interesting but suffers from some problems in my opinion. The first of these, and certainly the most important, is the keyboard. The tactile switches used are not suitable for precise, regular and comfortable typing. These are front panel switches, intended to configure a device, but certainly not to serve as an element of 'dialogue' with a computer. 

I'm not even talking about the self-adhesive plastic film where the key symbols are printed. It just makes typing painful : 


So I decided to create a keyboard equipped with real input keys. For this, I start by creating a prototype of what should be the type of keyboard that I will use for my future developments :


After a few days of waiting, I received the printed circuit board and soldered the components that will allow me to perform the programming of the on-board microprocessor :


Why an embedded microprocessor on this keyboard? Because this will allow the development of a keyboard, I hope, adaptable to a large number of materials, without having to recreate it each time.