Bytefest 2019

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These were the computers we brought to Bytefest – a Czech vintage computer show. David and I decided not to bring more than two desktop systems. Amiga 2000 was an obvious choice – we fixed it not a long time ago and I played a lot with it recently. The other computer was SGI Indy with the original set of peripherals including the Indycam camera. There are not many vintage UNIX computers to see on vintage computer shows in this country. Thus, it is my duty to bring at least one every year.

The Aritma Minigraf plotter sitting on top of the Indy was connected using one of the Indy’s serial ports though a special ARM-based module that David built. The module contained the control software that allowed it to draw faster and with better precision than the plotter was originally designed for. From time to time, there were couple of people standing in front of the plotter, being hypnotized by the smooth movement of the pen. The Indy itself was communicating with the module as a serial terminal with the ability to send HPGL files that needed to be drawn.

I’d never played that much with Indy before (aside creating the OpenGL 1.0 version of our 3D graphics benchmark) and this was a nice experience. The graphics card in our Indy is able to display no more than 256 colors (or 16 colors for double-buffered 3D), but it’s pretty fast and allows you to have a different 256-color palette for an active window and the rest of the system. Therefore, the color flickering effects are minimized in comparison with PCs set to 256-color modes. I was surprised by the visual quality of the composite input from Nintendo 64 in 256 colors.

Commodore Amiga 2000 was configured to show the capability of this platform during the late 80s (thus, Workbench 1.3 and Kickstart 1.3 only). It didn’t have any accelerator board and the only expansions were a simple hard disk controller, 2-MB fast RAM card and A2088XT PC emulator (with an 8088 and 512kB of RAM). During the show, I also added an ISA card with a serial port (for Microsoft InterLink purposes) and a VGA adapter.

The other devices that we showed were: Apple PowerBook 100 (this year with a working hard drive and full of software), Digital DECpc 325SLC (because a 386 with color LCD is cool) and HP OmniBook 900 (just a service laptop to convert the Wi-Fi Internet into a cable form for the Indy).

Amiga for Bytefest

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I’m still preparing my computers for the upcoming Bytefest. Amiga 2000 with a A2088XT PC emulator card is the second computer I want to have there. Unlike others, I want to show the computer with Kickstart 1.3 / Workbench 1.3, original upgrades and late-80s programs.

I often see only heavily expanded Amiga systems with latest versions of Workbench, PowerPC accelerators and PCI cards. However, these machines don’t say much about this platform when it was really used by professionals.

Preparing my SGI Indy for a vintage computer event

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Bytefest 2019 is coming and I have only two weeks to prepare all the machines I want to take with me. I want to the show this Indy with a Nintendo 64 game console because Indys were often used for N64 game development (after all, N64 hardware was designed by SGI). It is nice to see that Indy’s VINO interface supports progressive scanning (used by game consoles and old 8bit computers) on its composite/S-Video inputs – unlike newer SGI O2 and SGI Visual Workstation 320. Anyway, the main planned part is to connect a vintage Czechoslovakia plotter (Aritma Minigraf) using our custom interface (modified to use a serial port) and plot processed images of visitors taken using the Indy’s bundled webcam.

I’m surprised that serial ports on Indy support speeds only up to 38.4 kb/s. Pretty slow for a computer introduced in 1993. Maybe that’s one of the reasons why the serial port speed was not even mentioned in the user guide. They just didn’t care.

Certain Impact on SGI

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This is my favorite photo from the Bytefest vintage computer show last year. A little girl playing Certain Impact on my SGI Octane2. Certain Impact is a flight simulator created by Paradigm for SGI in 1995. It was used as a graphics demo for the Indigo2 IMPACT line of workstations.

Grand Prix Circuit running on Apple PowerBook 100

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The game runs smoothly on the 16-MHz Motorola 68000 and has better music and sound in comparison with the PC version. Unlike other passive-matrix displays of the era, this 640×400 1-bit panel from Sharp is really fast and makes the game quite enjoyable.

Bytefest 2018

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I’ve brought some of my computers to Bytefest (a big Czech vintage computer show): Apple PowerBook 100 with an external floppy drive, IBM PS/2 P70 as a cool gas-plasma-screen serial terminal, SGI O2 (used only as a hard drive cloning machine running in headless mode), SGI Octane2 with all necessary peripherals and DELL Precision M50 for sharing wireless Internet connection with my other machines (and also to show how the graphics workstation market changed in less than two years from Octane2).

CP/M running on Sinclair ZX Spectrum +3

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Unlike previous ZX Spectrum computers, +3 is equipped with an internal 3-inch floppy drive (compatible with Amstrad computers) and it is fully capable of running CP/M. The system runs snappier and more responsive than Commodore 128 in the CP/M mode but there are two caveats. Multiple keys are missing in the crippled keyboard layout and these are replaced with cumbersome keyboard shortcuts. This can be especially annoying when working with spreadsheets.

Another issue comes from the fact that the video circuit works in a resolution of 256×192 so it cannot handle the standard 80×24 text-mode typical for CP/M machines. The computer normally displays only 32 characters per row which would not be enough for any CP/M program. The +3 version of CP/M therefore uses a reduced font resolution with just 5×8 pixels for each character (including space between characters). Such font allows to display 51×24 characters and that’s the default text mode when +3 is booted in CP/M.

Of course not all programs work correctly with the reduced screen size so there is a program called SET24x80.COM. It provides a virtual 80×24 screen and you can quickly switch between displaying the first 51 columns or last 51 columns of the screen using a keystroke.

In Front of Osbornes

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This is me*… five years ago in front of Osborne Executive.

*) the one wearing the Space Invader T-shirt

Kids and Old Computers

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There is a way to see many old computers running in one room in Czech Republic. It’s called Bytefest and it is probably the biggest public retrocomputing event in the country. I took about twenty computers in my car with me this year in order to show the evolution of portable computers.

There were a lot of people walking around and some of them brought their kids. It is somehow nice to see little kids trying to do something with computers that are few decades older than they are. When they grow up there is a high chance that these computers will not work anymore.