ZX81 Computer


Showcasing monthly programs, a retro look at my my first computer., Page 5
Octoberís Program: PAC-MAN

Octoberís program, PAC-MAN, may leave you a bit confused. Inspired by that iconic arcade game, this version has no graphics. It does have dots, cherries and ghosts. It doesnít, however, have any pictures of those elements. Give it a try and youíll see what I mean.

Posted Oct 04, 2012 by Steven 3 min read

Septemberís Program: Runner

Septemberís program, Runner, is nostalgic for me. When I wrote this program I had moved on to my C64. My ZX81 was starting to gather dust as I was busy learning the ins and outs of my new computer. For some reason, something tugged at me to fix my ZX81 keyboard and get it running again. After transplanting the ZX81 brains into a TS1000 case, it surprisingly powered on. I wrote Runner as a test that still worked. It did. That was the last time I was able to use the computer that had been my pride and joy for the previous three years.

Posted Sep 01, 2012 by Steven 3 min read

Augustís Program: PAC-MAN Video

Wow, August flew by way faster than I expected! Here we are at the end and I finally got around to uploading the monthly program. This monthís program, PAC-MAN Video, is a bit different. Although I call it a game, it doesnít really play like one. It is totally random with a slight nod to you. Skill isn't required, just give it a try.

Posted Aug 26, 2012 by Steven 3 min read

Julyís Program: Can Punch

Iím back to the basics for Julyís program. Can Punch is a simply graphic game that will probably infuriate you more than entertain. Donít believe me? Go try it and decide for yourself. The goal is punch the can thrown at you. Use ďZĒ to raise your fist high and ď.Ē to lower it. A deceptively simple game mechanic that I dare you to master. I double dog dare you!

Posted Jul 22, 2012 by Steven 2 min read

Juneís Program: Pole Dodge 2

Yes, I know Iím late. June is almost over and Iím sure my adoring fan is up in arms. I do have one fan, right? In any case, Iím breaking tradition for Juneís Program of the Month and posting a more modern program. Pole Dodge 2 is my revamped version of Aprilís program. Before I dig into the details, go play it. Itís real easy, just use the ďZĒ and ď.Ē to bank left or right. No really, go play it. I think youíll find it much more enjoyable this go round.

Posted Jun 25, 2012 by Steven 4 min read

May's Program: Jet Flyer

Jet Flyer is May's Program of the Month. Although a bit late, I believe it is a bit better than last month's and worth a quick try. The goal is to keep your jet on course by using the ďZĒ and ď.Ē keys to bank right or left. It isnít an overly hard game. You just need to keep the course indicator close to zero. I wonít say how close to avoid spoiling the fun.

Posted May 20, 2012 by Steven 2 min read

Aprilís Program: Pole Dodge

Pole Dodge is Aprilís Program of the Month and it is an odd one. Partially odd because I typed it in back in February, and partly because the program just doesnít play well. I know that doesnít lend well for one to give it a try, but try it you should. Why? Because the premise isnít bad. It is the execution that leaves a bit to be desired. Of course, I blame the slow hardware.

Posted Apr 01, 2012 by Steven 3 min read

Marchís Program: T.W.M.

T.W.M. is Marchís program of the month. It is a simple animation that tries to mimic a computerís destruction of its defined target. February was actually pretty prolific for me as I transcribed this and another program, as well as updated a number of older programs using MCODER. Fortunately, that means I have a few more programs available than I normally do. Of course, one is more than I normally have ready so Iím not sure that means much. Anyway, go give it a try and enjoy the animation in all its simplicity.

Posted Mar 05, 2012 by Steven 2 min read

E.T. Redux

E.T. may not have been my best game ever, but it was an interesting exercise in 1985. Loosely, and I really mean loosely, based on the Atari 2600 game, E.T. follows the exploits of the title character as he tries to find his way home. Originally written in ZX81 BASIC, I revisited E.T. to better understand how to use MCODER II. I was ultimately successful in compiling it and getting it to run. If you are adventurous, you can compare it to original version, bugs and all. Instructions for E.T. are available off my old ZX81 website.

Posted Feb 20, 2012 by Steven 5 min read

Playing Around

It isnít all programming around here! Some days it is fun to just play around. I was adding an image to my other site which led to me reviewing some of my old Flickr images.

Posted Feb 16, 2012 by Steven 1 min read

Road Hog Improved

What's this, another version of Road Hog? Yep. This is Januaryís Program converted to machine code using MCoder II. I was surprised how easy it was.

Posted Feb 14, 2012 by Steven 1 min read

Februaryís Program: Light Walls

February is upon us and that means another program of the month. This month it is another one from 1983: Light Walls. In case you hadnít guessed, it has its roots in Tron. The game requires you to steer right (ď.Ē) or left (ďzĒ) to avoid hitting the light walls. I wrote this program while a friend was over and we took turns trying beat others high scores. Who says you need color and 3D graphics to have a good time! Not convinced. Give it a try yourself and see how good your reactions are.

Posted Feb 09, 2012 by Steven 2 min read

ZX81 Emulator on Android

As more and more people turn to mobile and tablet devices for their entertainment and consumption needs, it is becoming harder to share my ZX81 preservation project. I remember how excited I was when I found a Java based emulator that would run my ZX81 programs on the web. Although Java and I havenít always gotten along, I was happy to be able to show off my programs on the go with nothing more than a browser available. To my surprise, however, Java isnít even part of the conversation when talking about those on-the-go OSís like iOS and Android. All that effort isnít of much use when a large portion of your audience canít enjoy it. Fortunately, and much to my surprise, I ran across Zed Ex (Beta) in the Android Market. You can also find it on AppBrain.com.

Posted Feb 05, 2012 by Steven 2 min read

Januaryís Program: Road Hog

Welcome to the new year! Starting off the second season of monthly programs is January's program Road Hog. Road Hog is a driving game similar to my later Flywheel game. I hesitate to call it a racing game as there is no acceleration. You just move the car left or right using the ďzĒ or ď.Ē keys. The game is pretty easy due to the slow speed of the animation. Go give it a spin.

Posted Jan 14, 2012 by Steven 3 min read

A New Year of ZX81 Programs

Well, the celebration of thirty years since the introduction of the ZX81 is now over. For the last year I've been bringing you an original ZX81 program each month as a tribute to my first computer. It was a lot of fun typing in those old programs or fixing tape recordings I made back in the eighties. I even rewrote one which brought me back to those old programming days. For those that found your way here, I hope you enjoyed my ramblings about the programs. Perhaps you've learned something or I just invoked a kinship from a fellow programmer.

Posted Jan 10, 2012 by Steven 2 min read

Decemberís Program: Creature

I canít believe December is here and the year is almost over. To celebrate the last program of the month, I present Creature, an animation program. Unlike many of the smaller programs submitted throughout the year, this one is the largest weighing in at 14KB. Although Creature isnít as exciting next to more modern computer animations, I still find it interesting to see what could be done with this little machine 26 years ago. Give it a watch, enjoy the nostalgia, and try not to laugh too much.

Posted Dec 03, 2011 by Steven 3 min read

New RSS Feed

As of today, you can use RSS to subscribe for your monthly dose of ZX81 goodness. I originally hadnít planned to offer an RSS feed for my ZX81 site. The original goal was to cross-post articles to my main site and rely on its feed for subscribers. Sadly I tend to forget to cross-post.

Posted Nov 20, 2011 by Steven 1 min read

Novemberís Program: Lander 2

November is here and the year is flying by. This monthís program Lander 2 is an earlier one from 1983. Oddly, the game displays Space Lander. Not very original as Iíve used that name before. Iím using the name I noted in my listing.

Posted Nov 03, 2011 by Steven 2 min read

Octoberís Program: 1985

Octoberís program is one of my later games from 1985 which is aptly named 1985. It has decidedly simple game mechanics. Set in an alternative reality, the Earth is gone in this version of 1985. Humans are colonizing Earth II, but you need to clear the mountains for agriculture needs. Yes, your job is to hit any key to clear the land. Things couldnít be easier, right?

Posted Oct 03, 2011 by Steven 2 min read

Septemberís Program: Odyssey

This month I present another simple game, Odyssey. It doesn't include instructions, so here is a quick synopsis. An evil computer has trapped you in a space ship. To escape, you have to remove the memory boards in order to shut down the computer. Sounds familiar? Obviously this program was inspired by 2001: A Space Odyssey. To play, use ďZĒ to move left and ď.Ē to move right. Hit the ďMĒ key to remove a memory card. Try to remove all of them in time to beat the computer.

Posted Sep 03, 2011 by Steven 3 min read

Space Lander 2011

I couldn't leave well enough alone. All that analyzing and nitpicking of the original Space Lander made me wonder what it might be like if I had rewritten it. Almost 28 years later, here is the reborn version of Space Lander 2011.

Posted Aug 21, 2011 by Steven 4 min read

Augustís Program: Space Lander

Okay, this may not be the large program I promised, but I choose Space Lander for a different reason: it's horrible! Okay, maybe it isnít that bad, but it definitely wasnít one of better programs. This was from 1983, clearly one of my earlier attempts. Actually, it is kind of refreshing reminder how much better my programming has become. If this helps others learn, then by all means check out the listing.

Posted Aug 17, 2011 by Steven 3 min read

Julyís Program: Sugar Cube Munch

Another simple program. Like many that I wrote for the ZX81, Sugar Cube Munch was small with a singular purpose. In this case, the goal is to eat all the cubes of sugar as quickly as possible. Once all the sugar is eaten, the game is over and the number of turns is revealed. You can give it a try by using the ZX81 arrow keys 5,6,7, and 8 to move around.

Posted Jul 03, 2011 by Steven 2 min read

Juneís Program: Beo One

I was searching through my stack of programs and decided to choose a short and sweet program for June. Beo One is definitely short, clocking at just 33 lines of code. Well 35 if you include the two new save and run lines I added. This is a simple talking head graphic program, which is the sweet part.

Posted Jun 06, 2011 by Steven 2 min read

Mayís Program: BOLT

Can you believe it! First day of the month and I have a program uploaded! Okay, so it is another graphic one and isn't very exciting, or long. But hey, you can't blame me for not trying!

Posted May 01, 2011 by Steven 2 min read