Bitmaps on PalmOS

Bitmap drawing on PalmOS can be... fun. Specially when you are trying to emulate what the real OS might be doing. Let's see what can affect the result: Bitmap density: low, double. Bitmap depth: 1, 2, 4, 8, 16. Screen density: low, double. Screen depth: 1, 2, 4, 8, 16. Coordinate system: standard, double. Draw …

Reviving PalmOS

This yet unnamed project is an attempt to recreate the PalmOS environment on top of a modern operating system. In short, it is a collection of libraries providing basic functions needed by PalmOS, like dynamic heap management, storage memory management, bitmap manipulation, window handling, preferences, features, timers, etc. PalmOS SDK 5r3 was taken as a …

Recovering ZX-81 tapes

Back in 1983 I had a clone of the ZX-81 computer. The hardware no longer works, but for some reason I kept some cassette tapes. I know these tapes contained some programs that were not available anywhere else. I wondered if it would be possible to retrieve those programs and convert them to digital format, …

Starflight

Reverse engineering the classic DOS game Starflight.