CODE & BOOKS

Amiga · original game

Veldrin

A side-scrolling game for the Amiga 500, written on the bare metal with the operating system switched off. It boots from its own floppy, on a real A500 or in an emulator, with no Kickstart ROM needed.

Source codeThe book
Veldrin on the Amiga, an orange rock ceiling and floor framing a dark blue cavern that scrolls sideways.
Chapter 42 — a world that scrolls
Veldrin with the player's ship on the left, green enemies in the cavern and the score panel along the bottom.
Chapter 43 — enemies, score and the panel

Veldrin is the complete game of Amiga Assembly. Chapter 42 takes it from the specification to a world that scrolls; chapter 43 adds the enemies, the sound, the score and the finished disk. Its whole source is printed and commented in appendix J.

Everything the book built before it is in here: the Copper, the Blitter, hardware sprites, the vertical blank interrupt, Paula and chip RAM discipline, all working together on a machine whose bus is shared with the chips.

The folders ch42 and ch43 of the repository hold the sources and the reference binaries; tools/mkadf.py turns a binary into a bootable disk image for the emulator.

Where it comes from

Written line by line in Amiga Assembly:

  • Chapter 42: Veldrin I: from the specification to a world that scrolls · ch42/
  • Chapter 43: Veldrin II: enemies, sound, score, and the finished disk · ch43/