ZX Spectrum

ZX Spectrum (Speccy) is an old 8 bit computer, which was born at year 1982. Microprocessor Z80 is its heart, working at 3.5 Mhz frequency. First versions contained 16kB ROM with BASIC interpreter and 16kB RAM. But very soon were produced Spectrums with 48kB RAM called "ZX Spectrum+". This was the first computer, which some of us saw in their life. Later there were versions with 128kB RAM and music chip AY-3-8912.
Speccy was designed mostly for educational use, for these people without access to big hall computers, but still interested in computer technology. And it was designed as cheap as possible.
This resulted in really cheap price (relatively ;)), if you look inside ZX Spectrum, you will immediately understand it. Except 2 chips (Z80 and ULA), few memory chips, cooler, and some small things, there's nothing inside. This resulted in a little bit smaller performance of Speccy. It has one of the biggest processor frequencies (yes, 3.5 MHz was a LOT !), but when compared with other 8bit computers Atari and Commodore the Z80 didn't execute instructions in 1 clock-cycle but the execution time varied (most of instructions took 4, 7, or 11 clock-cycle to execute), so it was in fact slower, than Atari and Commodore. On the other hand, Speccy programmers got about 13(!) 16b processor registers (AF,BC,DE,HL,IX,IY, SP,IP,IR,AF',BC',DE',HL', if I didn't forget any) and very rich instruction set (I still miss the "conditional calls" instructions, while I'm programming at Intel 80x86 processors).
Next drawback, when compared with other 8bit computers, was the nonexistence of special graphics chip. In Speccy the image has been updated and created by ULA, what forced designers to make the graphics as simple as possible. (From HW point of view, not from programmers. From programmers point of view was the graphics programming "breathtaking", but after some time many solutions and tricks appeared, how to make it easier for programmer) There was just one graphics mode: 256x192 pixels, and this area was divided in 8x8 pixels squares, where each square could have its own pixel color, background color (8 colors), bright on/off, and flash on/off. (It is very similar to PC EGA/VGA text modes). So when you wanted just 2 color graphics, you got 256x192 pixels, but when you decided to do something in color, you were supposed to fit it in 32x24 squares of 8x8 pixels, what wasn't a fun sometimes.

As I mentioned before, Speccy was designed for educational use, but very soon first games for Speccy appeared. Firstly just simple adventures and logic games, but when programmers found the right way to do fast graphic animations even with Speccy strange graphic memory layout, fast action games appeared, and keep in mind, that Speccy was not at all planned for this. Later, when demos appeared on other computers, the demo scene did born on Speccy too. Mostly in England, Poland, Russia and Czechoslovakia (now Czech republic and Slovak republic), where Speccy and its clones spreaded widely.
In few years about 1000 (!) demos appeared for ZX Spectrum, some of them doing things at the limit of Speccy possibilities, things unbelievable and undreamed to sir C. Sinclair, when he was designing and producing first Speccy.

In year 1992 (as you could read in our history) Ped and Pavuk met at Sinclair club. And there you may find the beginning of Kosice's demo scene. (except people from Speccy club there were very few people active at demo scene in east Slovakia in the early 90-ties, maybe few Atari users and Prokop with his PC, and I couldn't remember anyone else)
In next few months we did with Tren 10 demos for ZX Spectrum ("Zer0 dem0", "Shortdigi", "J.M.Jarre-live", "RIGHT VIEW from Columbia", "Second attempt", "Pure black", "F.S.R.D.", "DemoBit'96 invitation intro" and "YES", together about 450kB of demos !).

Now our Speccys are covered with dust, but we still love to remember those old times (we are a little bit sentimental :)), mostly because of very nice people we met due to our "demo production" hobby. I couldn't name them here, because it would be a very long list, but they surely know, who they are. :)

Maybe, one time, when we will have about 5-6 week of spare time, we will take our old Speccys (or run emulators) and we will produce one more demo ... (and then later maybe one more ... ;) ... But we have always lack of time, so don't worry. ;)

If you wish to check some old demos for ZX Spectrum, take some Speccy (or get some good emulator) and use few of our Speccy demo archive links and check our last (till now) demo for Speccy "YES", which we find quite nice.

Ped, Pavuk and Tren / 7 Gods.