My Commodore 64 demos

I recently came across my record at the Commodore Scene Database, and was happy to find that someone had found and uploaded two demos I had written, back in my days as a member of the C=64 demo scene between 1988 and 1990:

(I was a member of the groups ‘Excess’ and ‘Thundertronix’ / ‘TNT’, going by the handle of ‘Mantis’.)

With the help of CBA, I was overjoyed to track down another long-lost demo, my crowning achievement on the platform:

If you’re curious, feel free to go read those wiki pages or download the .d64’s — they run fine in VICE, the Commodore emulator (amazingly). If you’ve only got time to check one, check Rhaphanadosis; it’s much better than the others.

I’m very impressed with VICE. As far as I can tell, it’s perfectly bug-for-bug compatible with the real hardware, playing all of the demos perfectly (apart from a little additional speed due to differing hardware performance). If you haven’t already got VICE set up, bear in mind that after installing it, you’ll need a copy of the C=64’s ROM images; here’s a local set.

Also, the Commodore Scene Database is pretty awesome — it’s a full-scale IMDB-style setup, tracking the history of the Commodore demo scene in massive detail. Nice work guys!

The demos were written 100% in 6502/6510 assembly. I developed them using an Action Replay cartridge’s built-in monitor; it had an assembler, but one which didn’t support symbolic addressing. In other words, every piece of assembly used hand-computed branch offsets, and every variable and subroutine was tracked — on paper — by memory location, rather than using symbolic labels. If you want to know what the monitor was like, the VICE built-in monitor is almost identical!

I wrote these when I was 16; part 4 of Rhaphandosis notes the date as being 20 May 1989.

It’s interesting reading the scrollers, and doing web and CSDB searches in follow-up to see what happened next — one of the other Excess members, Raistlin is now Robert Troughton, a successful game developer in the UK with several major titles under his belt.

A Google search for Thundertronix finds a copy of “sex’n’crime” zine, issue 17, July 1990, which notes:

one of the new groups formed in 1990 (jm: slightly off, I think) is THUNDERTRONIX, better known as TNT. they are based in ireland and are doing very well for themselves. they have, in my mind, one of the best coders in the uk, namely MANTIS. he is currently coding a game with many new routines, etc… hopefully he should get some demos out soon!

woo! Er, unfortunately that game never went anywhere. ah well. ;)

BTW, it’s funny reading my scrollers in those demos. At the time, I was convinced that the c=64 was a dead platform — yet here we are in 2008, and there’s still a thriving demo scene on the Commodore. Incredible!

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  1. Nix
    Posted January 10, 2008 at 02:59 | Permalink

    Wow. As a thirteen-year-old who’d just got a C64 at the time, I think Raphanadosis was the first thing I downloaded (well, actually a friend of mine, now another games developer, gave it to me: I didn’t have anything as expensive as a modem). I was impressed enough to dive into C64 assembler and start reverse-engineering to see how you got all that nifty stuff done, but of course couldn’t afford Action Replay either, so blew most of a year writing an assembler in raw hex opcodes (I could have written it in BASIC but that would have been boring): by that point I’d forgotten about my original motivation so moved on to writing programming languages in said assembler instead. But Raphanadosis was the start of it all, my first experience of a RISCish CPU.

    I had no idea I’d been lurking on mailing lists inhabited by the author of that holy work. ;)

    (The CIA text generator shows an early interest in mangling text in various ways…)

  2. nishad
    Posted January 10, 2008 at 03:19 | Permalink

    Fear the MANTIS!!!!

    Justin, you are a HUGE GEEK, but I love you.


  3. Pson
    Posted January 10, 2008 at 10:54 | Permalink

    Wohaa! And the past comes in beating me with a stick this early in the morning. I sure remember Excess and those demos. As a matter of fact I used to swap (er, exchange software on 5 1/4″ disks via mail (the old kind, with envelopes and stamps that you had to pay for)) with Raistlin for a couple of years around 1990 or so. Great times indeed. Programming assembler on the C64 still sticks around up in the grey matter … I started up VICE 2-3 years ago and actually managed to do some basic stuff (moving sprites around and a simple scrolling text) just from memory.Now back to reality…

  4. Alex
    Posted February 1, 2008 at 09:32 | Permalink

    Brilliant! That took me back. The music is superb. They sure don’t make em like they used to. MANTIS! Ho ho.

  5. Keith
    Posted May 9, 2008 at 12:58 | Permalink

    Man, that takes me back. I remember you showing me them back in ’90 (?) and showing off the still-awesome floppy-drive-lights-in-sync-with-music thing.

  6. Posted May 9, 2008 at 14:26 | Permalink

    @Keith: hey! long time no see. I wish I could find a copy of that floppy-light-flashing demo, I was well happy with that. There’s a possibility that Rhaphanadosis does that and it’s just the emulator can’t emulate it, but I don’t think that’s the case…

    @Nix, @Pson: thanks for the great comments guys ;) I’m so happy the demos got spread that widely. It was very difficult to tell how far they got at the time…