I had this idea the other day. One of the problems I’ve had with the ZX81 is printing numbers, which is pretty slow. Due to this, many of my games avoided printing them. delaying showing score until after play has ended. My idea was to try to find a way to speed that up. Not only did I find a way, I decided to implement it in an older game of mine: E.T.
A recent post in a Facebook BASIC group of a cat animation. A couple of other members converted it to their BASIC code of choice. Mine being the ZX81, I promptly worked on a version for it. I created a mostly full screen version, which tends to show how slow the ZX81 really was. In any case, it was quite a fun little exercise.
Okay, although not the worst ever, Dice Game is pretty dull. With only two dice, no strategy, and no replay value, you might think this an odd program of the month. But for the young teenager that wrote it, it was pretty cool in 1983. Let’s dig in and see why.
Foreign to many developers today, I have a notepad and binder full of ideas from my ZX81 days. The notepad contains early program snippets. In contrast, I have sketches and designs crammed into a binder. Flipping through it, I landed on a Star Wars sketch that became the basis for this month’s program.
Walls and creatures always make for a nice game and Faller, our program of the month, has both. It takes a bit of imagination, but watch the icky spider climb up the wall towards you. Their goal, of course, is to knock you off and claim the wall for themselves. Like any good hero, you sit at the top and move over the spiders using Z and .. But be quick and knock them off using M to save the day. Just don’t be a faller should you miss.
April is close to wrapping up and I was able to find time this weekend to type in another ZX81 game. Laser Blast, this month’s program, has you saving the world. Kind of cliché I know, but hey this was 1984. George Orwell’s novel didn’t come true, but at least we could blast alien’s with lasers. Use the Z and . keys to move and M to shoot your ray of death. But beware. The alien has a guided missile and it’s heading right for you.
Ah, spring time. As winter melts away, the weather goes haywire and it’s time to enjoy the bouts of sunshine, rain and the occasional thunderstorm of hail. Perhaps it’s fitting that in the middle of this meteorological mayhem that Computact came back to life. An outwardly simple landing game that is almost impossible to play. No matter, it demonstrates some interesting use of ZX81 BASIC as March’s Program of the month.
Digging through my listings, I struggled deciding what to offer for February. The first one I found was an adventure text game. Too close to last month's program, I decided against it for now. Further down in the stack, I found a code breaking program, but after entering it in I realized it needed work. The next program I pulled out, a graphic game called Teleport—ignore that spelling for now—ended up being just right.
Wow, 2016 and I’m still digging programs out of my stack of print outs. Kicking off the new year, I’m grabbing a story based program. I wrote Star Probe, our program of the month, in the style of a Chose Your Own Adventure book—and yes, I actually owned most of them. Although you can only enter numbers, Star Probe is actually an example of interactive fiction. Though not as advanced as an Infocom game, Star Probe delivers an interesting, if short, story to the player. Before I spoil where I drew my inspiration, go play it. It will only take a few minutes. Just try to ignore the horrible grammar and spelling of a 14-year-old.
July’s program is indicative of the BASIC programs you’d find in early programming manuals. Most books start out with pretty basic commands such as PRINT and INPUT. A Story mimics these early programs in a creative way. Similar to Mad Libs, you answer a series of questions and the program, well, tells you a story.
Fly is a simple program that, in the end, is both baffling and intriguing. Looking at first like a simple shooter, it acts very differently then one and, if you don’t know the rules, will make you crazy. Once you do know how to play, though, Fly becomes simple and repetitive. Our Program of the Month shouldn’t be in this place, but it is.
Mixing things up a bit, I thought I’d start off the new year without a game program. Instead, January’s program is Computer Talk, or Comp. Talk for short. Comp. Talk is one of several educational programs I wrote for reasons I’m not entirely sure of. Perhaps it was just the thing to do back in then. Many computer books, especially those that taught programming, had a mix of program genres. Whatever the reason, I wrote Comp. Talk as a way for the ZX81 computer to introduce itself and show a bit of what it could do.
August’s program is Cave War, a later program from 1985. It starts out similar to Hit Man, basically a scrolling dodge the wall game. But there is more to it than that. Once you get to the end of the tunnel, you find yourself in a cave and need to blast away at a wall to continue on. Oh, and if you hit the same spot twice, it resets. Can you make it out of the cave alive? Use Z and . to dodge the walls and X to blast away the ground. Good luck!
Sorry, still no Joust. It’s not where I want it and I’ve spent July working on my novel instead. That isn't to say that I’m going to leave July without a program of the month. Instead I’ve pulled from my original site to bring you one of my favorite programs, Block £ Spear. In this game you'll find yourself at the wrong end of a knight’s spear. Fortunately, you have a shield and can easily deflect the spear by using the Z and . keys to raise or lower your shield. Sounds easy? You might be surprised.
Okay I haven’t finished my remake of Joust yet, nor did I want to wait until the last week of the month to get an article out. Instead, I offer you Monster Maker as June’s monthly program. It’s pretty straight forward and anti-climatic against the power of today’s programs. Once you load it, enter in five numbers and type your monster’s name. That’s it. The program will then display a nicely formatted monster description based on your input.
For March's program of the month, I drew inspiration from one of my older demo’s, The Ball. Like many young kids from the early eighties using BASIC, I took a stab at animating a bouncing ball. It is a a relatively easy program to write depending on how complex you want to make the math. In my case, it is very simple math, no physics involved here.
Winter has set in and it is time to close out the year with a simple game. Dollar Sign, December’s program of the month, is that game.
For November, I’m looking both forwards and backwards. Although I wrote SNUNCH in 1983, I added a corrected version to my first ZX81 web page in the ’90s. SNUNCH was my early attempt at writing a PAC-MAN like game. Note that I said like, not clone. My goal was to be inspired, not to copy. Sadly, it isn’t very good, even after I fixed some of its logic flaws. Despite its flaws, I still believed it had potential and I set about updating it using MCODER II. It is this improved SNUNCH ML version that I offer as November’s program of the month.
I couldn’t help it. I updated Bonkers using MCODER II to convert the BASIC code to Machine Language. This improved the speed of the game making improving its playability. If you haven’t played the 1985 version, play it first so you can appreciate the difference. If you have, now give the 2012 version a try. Better?
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 month’s program, PAC-MAN Video, is a bit different. Although I call it a game, it doesn’t really play like one. It is totally random with a slight nod to you. Skill isn't required, just give it a try.
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 “Z” and “.” keys to bank right or left. It isn’t an overly hard game. You just need to keep the course indicator close to zero. I won’t say how close to avoid spoiling the fun.
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.
March’s program is Lock £ Fire. I wrote this graphic game in 1985, although I have to admit I don't remember it much. It is a bit hard to play as the keys aren’t very sensitive and the aliens jump around as you try to “lock” onto them. It doesn’t help that I used an odd keyboard layout which adds to the difficulty. The aliens are shooting at your shield and, if they get through, the game is over. Note that you don’t kill the aliens, but they may change their look. When you shoot them enough, the next level starts. Every 10 hits will clear some of your shields as well. Boy, I must have been in one of those moods when I wrote this.
What do you do on a lazy Sunday? Write programs of course! I was reading Tim Hartnell’s book Creating Adventure Games On Your Computer and ran across a little gem for generating random names. It is short and sweet and easily converted into Perl.
For some time now I’ve listed the ZX81 books I own on my original ZX81 web site, but I hadn’t put much effort in searching the web for them. Mainly this was because I already own them, but mostly because it never occurred to me to do so. I ran across an online copy of Sinclair ZX81 BASIC Programming which made me wonder what other books existed out there. Sadly, my search uncovered very little legitimate books. However, World of Spectrum did have a good number of the books and cover art available.