Computer Reminisces 1982: My ZX81








This is the one that started it all for me. I was 11. It was Christmas or maybe a birthday. Now It was Christmas. For my birthday I got the 16k Ram expansion pack. So, a 1k machine... think back to that. I haven’t thought about it for years until now but 1k... that’s 1000 letters... is a tiny tiny amount of memory. I spent a few weeks copying programs from the books and magazines. They might take an hour to do and then maybe (for me at least) a day to debug... going through the code bit by bit. My bugs were all typos. I have made many mistakes in my life, most of them are typos.

I remember my dad spent a night typing up the program to play chess that he found in a magazine. Chess in 1k yikes (Here it is! http://users.ox.ac.uk/~uzdm0006/scans/1kchess/).... I cant remember how it played but Deep Blue it wasn’t.

At some point I started writing my own programs. I did a game of Jaws where you had to get to "Cable Junction" while being chased by the eponymous shark. I don’t remember if it was good I am guessing it wasn’t. Then I made "Dogfight" the graphics of which were some kind of cross hairs in the middle of the screen, to make the enemy plane was this little collection of characters:

--=*=--

Pretty realistic, na?

"Fruit Machine" was the game I tried to get published. If I remember rightly you could print awesome graphical characters using special codes for things like a Spade, Heart, Diamond.... and these formed the heart of the game. With all the ingredients for excitement a game needs this was destined for great shakes.

I sent it off to a ZX81 magazine and waited for the reply. Aged 11 or 12....it came. I can remember really clearly opening the envelope from the publisher. It was a school day. To paraphrase it said something like:

"Dear Matthew, Like you, we may only have 1000 bytes to play with…but if you think we are going to publish that travesty of an excuse for home entertainment in our prestigious magazine you have another thing coming, sonny."

They were probably nicer than that but you get the drift.

Once I moved up in the world to 16,000 bytes (with the monolith of a plug-in expansion pack) the world was my oyster. With 16 Kilobytes I could.... well.... do more. I cant remember what though. It was a difference of kind not degree but it was not that tiny code and concept space that started me and thousands of others off. Once you got into that space and out of the binary straight jacket the world would never be the same.



(FYI This post is just under 2k.)