Рет қаралды 43,144
This is a playing of shiru8bit's excellent "Back to the PET" demo compo on physical hardware with amplified audio out. This is amazing software for a 1MHz 6502 microprocessor system packaged into a standalone 29KB "PRG" binary. This makes exclusive use of the "PETSCII" character set in 40x25 text mode.
This demo is presented on the physical hardware in a "dark mode" (lights off and screen focused) followed by a "light mode" (lights on and full view of the system). See 4:47 for the lights on version.
Demos like these are extraordinary forms of artwork! The original hardware system to do this was first available in 1977 (although most systems at that time did not have a full 32K of RAM and would need a CB2 mod for the audio). By mid-1980, 32K RAM became more widely available/affordable to home consumers, and the 40XX series of Commodore PET included a piezo speaker for the CB2-style audio out. Crafting this kind of audio-visual experience on such an early home-computer requires very precise understanding of the instruction set and determining very clever coding techniques to pull off the desired effects (especially also while intermixed with audio, which represents a form of multitasking).
"Back to the PET" was developed using ca65 (6502 assembler) and multiple support tools, and an emulator (called VICE) - no physical hardware was available during the development. To see how this physical hardware playthrough shown here compares with the emulator, see shiru8bit's original recording here (also with links to the original PRG and source code):
• BACK TO THE PET - a de...
Presented with permission, thanks shiru8bit!
To emphasize: I didn't create this demo, it is the work exclusively of shiru8bit. But he didn't have a physical system to run the demo on, so this is a recording to demonstrate how fantastic the results of his dev and testing on an emulator translated over to the real hardware.
NOTE: "Back to the PET" is a homage to a scene in the "8088MPH" demo for the IBM PC (CGA), both inspired by the excellent "Back to the Future" movie released in 1985 with Michael J. Fox.
In honored memory of Jack Tramiel, Leonard Tramiel, Chuck Peddle. For an outstanding in-depth paper about the PETSCII character set, refer to:
acris.aalto.fi...
For other Commodore PET related works, see also:
- Attack of the PETSCII Robots
- Destiny Hunter for Commodore PET
- Jim Orlando's excellent Commodore PET software (Defender, Lode Runner, etc.)
- Commodore Stupid PET Tricks