April 22, 2019

My First Computer - Sinclair ZX81

Sinclair ZX81

Image from Wikipedia page for ZX81

Back when I was a lad, I started learning about computers at school. There was no official computer curriculum, but one of the physics teachers started a computer club, brought in a couple of his home computers and started teaching interested students how to program in BASIC. I was one of those students and I fell hard for the subject of computer programming and started spending many of my lunch breaks at the physics lab working my way through the manuals that the computers came with back then.

The computers that our teacher brought in were a Sinclair ZX80 (the forerunner to the ZX81) and the Acorn Atom. The ZX80 had 1K of memory, while the Atom rocked a massive 2K. Both computers had their own version of the BASIC programming language built into the computer. Home computers, at that time, did not have floppy disk drives, so the provided programming language was invariably burned into Read Only Memory, known as ROM, so that it was available as soon as the computer was turned on.

My parents quickly picked up on my new enthusiasm and were keen to capitalize on anything that might help my academic studies, which at that time were mediocre at best. We were on the poor end of being poor, so when my parents spent £100 on the newly released Sinclair ZX81, it was a meaningful financial sacrifice. I was strongly instructed that it was only for learning to program on and that I was expected not to play computer games on it all the time. Fortunately, I am not very good at computer games and I loved writing computer programs, so that was one parental instruction that I had no problem obeying.

The next challenge was finding opportunity to use the computer. The ZX81, as did most home computers of that era, displayed itself through a television and we had exactly one TV in the house. No one else in the house wanted to watch me learn to program, so I had to find times when I was not at school and no one else was watching the TV so that I could use it. The practical upshot of this was that I started getting up early so that I could get an hour of uninterrupted time with the computer and the family TV before heading out to school.

Initial teaching materials came in the form of the two printed manuals that came with the computer. This sounds extravagant, with most technology coming without printed manuals for many years now, but in the early 1980's this was an expected thing. After completing the manuals, I started getting computer books from friends or my local library. I also started reading computer magazines, both those aimed at teenagers like Your Computer and those aimed at adults with some technology experience, such as Byte. Many of the magazines contained printed program listings intended for their readers to type in on their own computers. I spent many an hour typing in other people's programs to try to run them and have something interesting to do with my computer.

Tags: Personal