VICFICKEN is an application for the Commodore 64 that lets you produce weird graphics by pseudo-randomly changing some of the VIC registers when you wiggle the joystick.
The application is free to spread and modify for any purpose, and the short source code is provided on this page.
The program was obviously inspired by glitchNES by NO-CARRIER.
Just run the program and use a joystick in port 2 to alter the screen content.
As of version 2, you can change the waveform (for different glitch patterns) by pressing the F keys: F1 for noise, F3 for saw, F5 for triangle and F7 for square. The default waveform is noise. If you press cursor up/down, you can enable frequency control over the waveform with a paddle in control port 1.
You can probably use something like MIDI2600 or Midify if you want the graphics changes to correlate more exactly to the music in some MIDI sequencer, but I'm not sure. Devising a MIDI to Joystick interface using an arduino and some 4066 chips is not too hard anyway!
Load a bunch of data into RAM before loading and running the program. The program works very much by just "looking" at the RAM in different locations (by moving the graphics pointers around randomly), so having something different there when you start the program will produce different results. You can for example load a game, then load VICFICKEN without ever running the game.
For discussing, feature requests, ideas, submitting patches or anything else you can contact me by mail or check out the discussion thread on 8bitcollective.
I'd like to thank InactiveX very much for providing me with a really nice homemade paddle controller FOR FREE! That helped development a lot!
Special greetings also go to NO CARRIER for the original glitchNES idea, to silreq for proposing paddle control in the first place, and to Slammer for the excellent cross-assembler I'm using.
Taken with VICE