[spectre] Galaksija, a Yugoslavian microcomputer...

[Andreas Broeckmann]

http://events.ccc.de/congress/2012/Fahrplan/events/5178.en.html


Tomaz Solc

The ultimate Galaksija talk

Everything about a Yugoslavian microcomputer halfway between a TRS-80 
and a ZX 80

Galaksija was to be in Yugoslavia what Commodore and Sinclair were in 
the west. Whether it succeeded or not, its deceptively simple design can 
still teach us a lot of interesting tricks on how to make a usable 
computer and operating system with as few transistors and bits as possible.

Galaksija was a Yugoslavian home microcomputer popular in the local DIY 
community throughout the 1980s. It was meant as an alternative to 
illegally bought contemporary Sinclair and Commodore computers. It is a 
fascinating product of the time of severely limited availability of 
electronic components and a widespread disregard for copyright.

This situation led to unique design decisions on both the hardware and 
software side. Galaksija can display better graphics than Sinclair ZX 80 
with only a small number of general-purpose digital logic integrated 
circuits. Since it included no specialized chips it was easy to build at 
home. Being constrained to a relatively small EPROM, Galaksija's 
built-in BASIC interpreter was based on a stripped-down and 
hand-optimised Tandy TRS-80 ROM. It relies on undocumented Z80 features, 
"racing the beam", executing error messages and floating point constants 
as code and similar tricks. By not including an auto-run feature the 
authors also made sure that Galaksija programs were hard to 
copy-protect, encouraging sharing and an early open-source like approach 
to developing software.

This is a talk inspired by the Atari 2600 and Commodore 64 ultimate 
talks from the previous Congresses and the 30th anniversary of 
Galaksija's design. In 45 minutes it will include a brief introduction 
about the history of Galaksija and home microcomputers in Yugoslavia at 
the time. It will then cover all aspects of Galaksija's hardware design, 
built-in ROM routines and original software that has been preserved to 
this day. It will end with coverage of what tools exist today to develop 
software for Galaksija, either for running in one of the software 
emulators, on hardware replicas or the real thing.

I'm an electronic engineer and this talk is based on my university 
diploma thesis about reverse engineering Galaksija's hardware and 
software design and tracing back its origins. I have designed and made a 
working replica using modern CMOS logic that preserves Galaksija's 
features, look and DIY-nature as much as possible. CMOS Galaksija has 
been presented in a number of retro-computing events and talks. I am 
also the author of a number of Galaksija demos and a Free software 
Galaksija developer's kit.