Preface
You can write a Z80 game as a set of facts, moments, and rules: declare what the program remembers, name the events that arrive from the player, and write what follows from each one as a few lines of assembly. Glimmer is a language built on that idea, and this book teaches it from the first lit pixel to complete, playable games.
The book is for you if you can read Z80 assembly: registers, flags, memory access, a short routine with labels and branches. Everything else is taught in place - what a game frame is, how game state works, how a reactive program decides what runs, and every tool you touch. If the Z80 itself is new to you, AZM Book 1 - Z80 Fundamentals starts from nothing and leads here.
Three tools share the work, and the book introduces each one where you first need it:
- Glimmer is the language and its compiler. A
.glimfile holds your declarations and your assembly blocks; the compiler turns it into one readable assembly-language program. - AZM is the assembler. Glimmer’s output is ordinary AZM source, and AZM assembles it into the bytes the machine runs - checking register use across every routine as it goes. The AZM books hold the assembler’s own story.
- Debug80 is the workshop: a VS Code extension that builds your
program, runs it on an emulated TEC-1G, and steps through it at
source level - in your
.glimfile, for the code you wrote. Debug80 Book 1 covers the environment in depth.
The machine is the TEC-1G, a Z80 single-board computer, and every program in the book runs in Debug80’s emulation of it. The same HEX file the build produces runs on a real board, so a physical TEC-1G turns every exercise into blinking hardware - the emulator route and the hardware route share every step but the last one.
The course moves in four stages. Chapters 1 through 5 build the mental model: state, pulses, bindings, and the three phases a frame runs. Chapters 6 through 11 add the instruments of the TEC-1G’s 8x8 LED matrix: drawing, timers, motion curves, shapes, sound, and structured data. Chapters 12 through 14 give programs their grown-up shape: helper routines, multiple files, and cards - the screens and modes of a real game. The rest of the book spends everything you have learned on complete games, first on the matrix, then on the TMS9918 video display processor, and closes by comparing how those two very different displays shape the games written for them.
The book teaches Glimmer 0.5.3. Every complete program in it was built
with glimmer build and runs.