Articles by Steven


Steven has written 481 articles.
Wasting Time Watching Circles in This ZX81 Demo
I ran across a ZX81 forum post showing a fast way to print a circle in BASIC. It was based on an article for the Atari back in 1983. I was surprised how fast the routine was and wondered how it would in assembly. Long story short, I built a screen saver for the ZX81…
Posted Sep 01 4 min read

A Super Fast Scrolling Demo on the ZX81
Totally divergence from working on Gem Quest. I got around to cleaning up my scrolling demo from last month. In doing so, it made me wonder would it would be like to code it in assembly. The answer is both bland and interesting. Let’s discuss why that is. # Starting from a base. The actually cod…
Posted Aug 16 4 min read

Super Simple ZX81 Scrolling Example
Although I've been busy working with the ZX81 this month, it has been with my Gem Quest game. Not much to share yet there, but I am working on it. To get in something for the month, I thought I’d share an updated demo program. # An old beginning. I was going through my old programs and found this…
Posted Jul 31 3 min read

The Monster From the Deep Arrives on Your ZX81
This month’s program is a super simple graphic program I created in 1984 called The Monster. Probably developed as a title screen, the graphic looks like some swamp creature with seaweed hanging off it. I’m not positive what I was going for, but it does look rather imposing. # A tie to an older…
Posted Jun 30 4 min read

Wandering Down the ZX81 Road
I had this idea on Sunday that led to today’s program—more about that in a minute. One of those sit down and do it programs, I banged this out pretty quick yesterday. Not wasting time, I decided today I’d share it. Road is a very simple program that I never intended to make…
Posted May 03 7 min read

Racking up a New Score in This ZX81 Animation
Not a lot of time for programming this month, but I did get around to adding coins to my running game. Funny how little things take time to hack about. I’m not completely happy with it, but it works. Run 3 ML does give a whole new meaning to infinite runner. # Grabbing all the gold. There still …
Posted Apr 30 3 min read

Adding More Movement to My Running Game
Well, hard to believe we are turning the corner on March and heading into April. Spring is edging its way in and it is time to get outside and work in the yard. This made me want to kick my ZX81 program to the curb, but it didn’t feel right. So, I bundled up my current progress on Run. # Pixel mo…
Posted Mar 30 5 min read

Working on Bones for a Future ZX81 Game
For some time now, I’ve wanted to build a running type game. The kind where there is a single key to press and releasing it makes you take an action. There are lots of variations on this theme, and it seemed like something fun to try…
Posted Feb 19 5 min read

The Long and Short of Rendering Lego Blades
Wandering through Mecabricks the other day, I ran across a fun pair of Mini-Katana’s by Shipmaster. Digging deeper, I also discovered his excellent Katana. Both models really appealed to me. Given my recent binge watching of Forged in Fire, both made for excellent subjects to render…
Posted Feb 17 3 min read

A Clean and Friendly Website for 2022
Over the last month, I’ve been doing some housekeeping on my website. I’ve had a few lingering issues to take care of. Unsurprisingly, this led me down a few different paths. From simple fixes to big ones, I’ve made a few subtle changes that impact the feel of my site…
Posted Feb 06 12 min read

A Cold Chalet Render to Kick off 2022
Having spent spent my time with physical LEGO builds lately, my render output has dropped quite a bit. Getting around to visiting Mecabricks again, I ran across a nicely designed model by Furbysims of a Chalet. Since it lacked a render, I thought to myself, “I can add one!” So I did. # A great …
Posted Feb 03 4 min read

Let’s Cook up a Faster Graphic Enlarger for the ZX81
I haven’t had much time for programming the last few months. To get back into things, I decided to take an old BASIC program of mine and rewrite it. Thinking about what to convert, my mind immediately went to Enlarger. It was a rather slow animation demo that could use an update. # Spoiled food …
Posted Jan 28 7 min read

Beach Fun for 2022
January has rolled around and it felt fitting to update my blog’s title screen image for the New Year. I was fortunate enough to get away to warmer areas and was able to capture this picture. It is my mood of late, looking out towards the horizon…
Posted Jan 09 1 min read

Digger Deeper Into My Water Bug II Game for the ZX81
Now, Water Bug II is an interesting game for me. I was so excited when completing the first version, that I wanted to build another version with ten more boards. The funny thing is, the games look a lot alike…
Posted Dec 25, 2021 11 min read

Water Bug Was My Attempt at a ZX81 Action Game
For most of the day, I’ve been thinking about my Water Bug game as I never really gave it a proper write-up. Finally got around to playing it again, I was surprised to find elements in that I thought were unique to Water Bug II are actually in this version…
Posted Nov 30, 2021 17 min read

An Early and Bad Attempt at a Yars’ Revenge on the ZX81
Like many teenagers in the early eighties, I was playing video games on my Atari VCS. Yars’ Revenge was a popular purchase, and I spent many hours dodging that stupid missile and trying to take down the shields of the Qotile…
Posted Oct 31, 2021 4 min read

Building a Better ZX81 Digital Rain using Z80 Assembler
My original plan was to create an z80 assembler version of Moon Lander. But with the trailer release for the next Matrix movie, I found myself revisiting another program. Built entirely in machine language, Z80 Digital Rain expands on my previous version with a splash of color…
Posted Sep 25, 2021 8 min read

Amping up the Visuals and Gameplay in Moon Lander V2
Last month, I shared an old moon landing program I wrote back in the early 80s. Right after that, I decided to give it a bit of a face lift, updating the visuals without changing the game play. Moon Lander v2 is my updated game, yet still the same BASIC code under hood. A fun new look. As I noted…
Posted Aug 21, 2021 8 min read

Try Not to Crash the Moon Lander in This ZX81 Game
When I first started programming, one of the games we would play on the old teletype machines was a simple moon lander game. The premise is you would use your thrusters to softly land on the moon. Moon Lander was my take of that program a few years later. A trip down memory lane. I actually enjoy…
Posted Jul 31, 2021 6 min read

Your Imagination Is Required With Comp Control for the ZX81
As a young teenager, I often wrote programs that I would integrate into other play. In this case, I had probably watched War Games again. The idea of a computer talking to you made for some fun fantasy play…
Posted Jun 24, 2021 7 min read