View Z80 Tag


Have some fun! Explore the 7 articles tagged with z80.

Meow in Motion: A Z80 Assembly Version of a Classic Cat Animation on the ZX81

Fast Cat (Cat ASM), ZX81 Screenshot #2, 2023 by Steven Reid

After finishing the basic version of the cat animation, I wanted to improve the frame speed. This meant converting from BASIC to machine code. My first thought was to do the conversion with MCODER II. I dropped that idea, deciding to focus on a custom z80 Assembly version. Ergo, cat written in assembly or Fast Cat is, well, a faster version and a bit more.





More Mandelbrot Set Fun in Z80 Assembly

Mandelbrot Sets Machine Code, ZX81 Zooming In Screenshot, 2022 by Steven Reid

Okay, after finishing my BASIC program version of Mandelbrot Sets, I decided I needed more speed. I wasn’t sure if I could write a version in assembly. My concern was the floating point math. After a good amount of research, and trial and error, I finally got a version working. This is my story.


Having Fun Learning How to Draw Lines on My ZX81

Picture Asm, by Steven Reid, 2021

When Simeon Dwyer shared his machine language line drawing routine, I immediately thought of redoing “The Picture.” Most of my z80 assembly has been with my Gem Quest game. I decided it would be a nice diversion to work on something else, even if a quick one. Picture Asm is the result of that diversion.


A Developer Diary in Pictures for Gem Quest, a ZX81 RPG

Gem Quest, Darkness Screenshot by Steven Reid, 3/07/2021

If you’ve been following me the last couple of months, you know I’ve been revisiting Gem Quest. Intended to be an Ultima style game for the ZX81, outside of a few demo’s I really hadn’t gotten far. That isn’t the case now. I’ve spent the last month learning z80 assembly code and hacking my way through the game. Tracking my progress, I’ve been capturing that journey in pictures and movies, which I’ve uploaded into a Flickr album.