ZX81 Computer

• Home
• Articles
• ZX81 Computer

The eighties were a turbulent time. Political turmoil grew out of the Cold War, which wasn’t loss on this teenage programmer. The vocal leaders of the US and the USSR bubbled up often in the pop culture of the era and the esclation of war. It shouldn’t be surprising that I’d create an animation depicting that escalation.

In my youth, I often looked to real games for inspiration. Card games were one such source and one I drew from often. Some attempts, like Stud, were simple high and low games. For March’s program, Hit tackles the more complex Blackjack, eschewing graphics to focus on gameplay.

I dug into some older games for February’s program, Missler. A simple yet effective game, Missler is a great example of programs I dealt with in the eighties. In this case, you must maneuver our anti-missile artillery in an attempt to stop the incoming barrage.

The start of the 2019 year is passing quickly, so I needed to get a game in quick. I found a short little program called Trench Runner, but to my surprise, it had two listings. So, I took advantage of the situation and am offering two ZX81 games for January.

Over the holidays, I dug through my listings to see what was left. I still have quite a few left, but the pile is definitely smaller. I’m starting to come across games I don’t remember as much. The Monster, this month’s program, is one such game.

I’m running a bit late this month, but I’ll try to make it up by offering a larger game. Of course, it wouldn’t be the Eighties unless it was almost impossible to play. But, at least it looks good.

Funny enough Lander, October’s game of the month, came out after my Lander 2 game. Weird, huh? No matter, it is a fast and sometimes difficult, sometimes easy, video game. Go give it a try, then let’s dig deeper.

September has come to a close and I’m on the edge for getting my program of the month out. So, I chose Raceway as a simple game that is both tough and satisfying. My high score is 40. Can you beat it?

August’s game is a somewhat deceiving. On the surface, it is a simple direction shooter. Be careful, though, as those asteroids speed up. It may start out easy, but Asteroid £ Metor will frustrate you—as it did me. After you give the game the retro try, let’d dig deeper into it.

Here it is in July and I have another one of my dodging games to share. But, this one is a little bit different. You don’t need to dodge all of them, or in this case go through all of them. Nevertheless, if you want the juicy bonus points, you need to grab as many of the blocks as you can. The twist is how the pylons change as you play.

You may, or may not, have noticed the lack of writing on my ZX81 site. You might think I gave up, moved, on, or forgot my password. Nope to all three. It’s way worse. I’m changing things up! TL;DR: You can head over to my main site (https://www.reids4fun.

I seem to like avoid the wall games. I wrote many of them over the years, inspired by other games I played like “Cavern’s of Mars.” It isn’t a surprise as the ZX81 made it pretty easy to write a vertical scroller. For Death Maze, I added a little twist. Is it enough to make the game fun to play? Let’s find out.

I had lots of ideas as a teenager. Many of them became actual programs, while others languish in my notebooks. Others made it a bit further, becoming programs on my ZX81, but never finished. A journey abandoned is still a journey. Let’s explore one such program this month: Tower of Love.

Jim notified me earlier this month that I’d missed one of his remakes of my ZX81 programs when I blogged about them earlier. Tower Dodge for the MC-10 is Jim’s version of my updated Pole Dodge 2. Not sure how I missed it as he rewrote it back in 2014. Of course, I can’t believe I wrote mine back in 2012! Time sure flies—get the pun? Anyway, let’s dive in and see what’s new.

Wait what? Another month? Another game? You betcha! April is upon us, and pretty much over. So, to pass the time I introduce Blaster, a shooter with a twist. Use Z to move left, . to move right, and M to fire. Not the most exciting game ever, but you’ll find it hard enough to spend a few minutes with it.

Taking a turn from games, March's program is a bit more useful. Although not as flexible as some modern programs, Bar Graph does the job. Add some data and print. What could be easier? Well, a lot.

I’ve been wanting to create my own version of digital rain for some time. The effect is well known from the Matrix movies, which used florescent green characters. Inspired by that version, I decided to go retro and generate a black and white stream of characters using the ZX81. Let the geekiness begin.

While digging around my site’s SEO this morning, I ran across these great videos from Jim Gierrie. Both depict his remake of Flywheel on a a TRS-80 MC-10. He had shared in a comment on my site, but I’d missed it given how busy last year had been. I love that Jim took the concept and made it his own, exactly the purpose of this site.

Nothing starts the year out better than a space shooter. The top of the printout was quite faded, so I wasn’t sure about ZTSXXSTZ when I started to type it in. But, once I got the first few bits working I realized I had something worth sharing.

Although may of my early programs were games, I spent a fair amount of time experimenting. December’s program, Slow Down, is one of my animation experiments. It is a straight forward sprite animation, with a twist. I used the ZX81 against itself to slow it down. If you’re ready, let’s dig deeper.

Back in 1983, Star Wars imagery flooded my life. With the release of Return of the Jedi that year, it only fueled the inspiration of my young teenage self. So, it shouldn’t come as a surprise that I would create games with that look and feel. Star Fight, this month’s program, is one such game.

There are a ton of windmills in Idaho. Mostly big ones for power, but you see a few smaller ones used for irrigation and wells. But, when I wrote this month’s program, I couldn’t remember any being around where I lived in Indiana. No matter. I still wrote a simple windmill animation, and today is the day to share it.

After upgrading to macOS High Sierra, I ran into a minor problem. Seems my WineSkin wrapper for EightyOne, my ZX81 emulator, stopped working. I have alternatives, but the screenshots I take from EightyOne are too nice to pass up. As luck would have it, there is a fix.

To date, most of my programs have been games and animations. It may come as a surprise that I also wrote a word processing program. Using a custom printer command, I designed a font that would allow you to use lowercase letters. Let’s explore September’s program of the month to see how that worked.

Tarantula, August’s program of the month, was part of a pair of games that made me think I was a game developer. At the age of fourteen, I didn’t let problems like the lack of a distribution channel tarnish my dreams. Although I didn’t make it into gaming, it’s still fun to look back on what could have been.