Welcome to TreeOS! This is a very simple, hacky, but working, "demo" that draws a spinning Christmas tree and a small message while running on bare PC hardware (no underlying operating system), using only standard VGA hardware. Merry Christmas!
This demo is a bootable floppy disk. it is pure 16-bit code, and uses the BIOS to load data from the boot disk and change the video mode, before operating directly on the VGA framebuffer. It uses a standard 320x200 256-color mode (VGA mode 13h). This should work on any reasonable PC hardware at all, though I've only tested it on a virtual machine (QEMU).
The default version floppy.img is actually a 4-sector (2KB) demo, but make floppy_1sector.img will build a true 1-sector (512-byte) demo, missing only
the text on the screen.
You will need nasm to assemble. If you have nasm and qemu installed, you
should be able to just make qemu on Linux. E.g., on Ubuntu:
apt install nasm qemu-system-x86
cd treeos/
make qemu # or: make qemu_1sector
Released under GNU GPL v3+. Copyright (c) 2019 by Chris Fallin <cfallin@c1f.net>.