ZX81 Computer

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I have some sort of fascination with code breaking. A byproduct of all the spy movies I watched as a kid. A friend of my would make spy cases with Lego’s, and I had to build my own of course. I had a wallet with home made credentials and so on. Code Searcher is a bit of a homage to those golden age gadgets of the 60s and 70s.

When I was a child, I remember going over to a friends house and playing Wizardry on his Apple. Leaving his house, I was super excited about the game I saw. Although my lowly ZX81 was no match, I had visions of creating my own games like it. My attempt, although a test, could have been so much more.

A bit cliche by 1985, but I was obviously still playing Frogger and the clones it spawned. With all its dodging and moving, the game is classic for good reason. Even in modern times, it has spawned the likes of Crossy Road and other in spirt games. My own attempt, called Sea Cross, finds you trying to get your family safely across the water and home. I doubt you’ll be able to.

The ZX81’s graphics be a lot of fun to program. Although I wasn’t a big fan of the PLOT command, I do have some examples of its use. My taken on the TS logo for the rock band Twisted Sister is one one example. Like a primitive screen saver, it can be fun to watch.

Okay, I’ll admit that I was a Star Trek junky. As a kid, I remember eagerly waiting each week to watch reruns of the original series with my family. When 1983 rolled around, I’d watched both of the original movies and owned the comic books that bridged the two. As such, creating a Star Trek game on my ZX81 should come as no surprise.

Running platform games with simple controls were all the rage when mobile gaming got started. Although the themes varied, they all tended to have a few if only on control to them. Some made you press down and release. Others ran on their own, requiring you to press or swipe as needed. My journey into the genre began in 1985 when I wrote Bolder. It may not be popular or exciting, but does show that the concept had roots going deeper than you may realize.

For November, I found another missile defense game that I wrote a few years back. I honestly didn’t remember this one until I started to play it. Starting off a bit slow, I kept telling myself that it should speed up. And, it did! Guess, my memory isn’t that bad after all. Let’s dig into Laser Catch a bit more.

Fall weather brings colder weather, colorful trees, and Halloween! The original movie was still a classic in 1984, even if a few sequels had been released by the time I wrote this program. Lacking the chills of the movie, my Halloween tries to convey the futility of running. Michael always wins.

Closing out September, it is time for a little adventure. SLR Venture is my attempt at creating one using the ZX81’s tiny memory footprint. Although I went on to write some more complex text games, this random game does a decent job.

As my programs attest to, I did a fair amount of digital drawing on my ZX81. As noted in past articles, I tended to use graph paper to design my games. Yet in 1984, I built a simple drawing program called Picture Use. Sadly, I never used it.

Although July nears its end, patriotism remains. From the frantic happiness of the 4th, to general love of country, July is about fireworks and Summer heat. Digging into my archives, I found a US Flag to commemorate the month.

Not all programs need to be games. And, in the case of Screen Copy, it is a demo program that ultimately became a utility. Most of us take the idea of making a screen shot for granted. Yet, back in the early ’80s, the idea was uncommon. That didn’t deter me.

Taking a minor departure this Memorial Weekend, my ZX81 program is actually from my childhood best friend. Neighbors during our time in Italy, Jeremy and I spent a lot of time together playing with our LEGO bricks, D&D, and on our computers. U.F.O is a simple shooter game that takes a unique approach to graphics.

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.