Jonathan Cauldwell (ZX Spectrum Dev) – Interview

Those of you linked to the current Spectrum scene will know the name. For those of you who didn’t even know there was a current Spectrum scene please let me introduce a fascinating chat (and also an amazing Spectrum insight) with a man who’s created more Speccy games than you can shake a stick at – Jonathan Cauldwell.


You obviously have a real love the ZX Spectrum – how did you first come to fall in love with this classic computer?

It was in the summer of 1984. I’d just bought my first computer, a second-hand 48K Spectrum. The games were amazing – Pssst, Zzoom, Escape from Krakatoa and many others. I’d spend hours playing them every day. What’s more, they were written in a mystical “invisible” language you couldn’t see.  You couldn’t list the programs the way you could with BASIC. It all seemed like magic. In fact it still is. The Spectrum is a little black box of magic just waiting to be brought to life.


How did you first get into making games and do you remember the first ever game you created?

I started out trying to write games in Spectrum BASIC but while it was powerful, it was nowhere near fast enough to be able to achieve the results I wanted. It was clear that machine code was the only way forward if I wanted to write the sort of games that other people would want to play. Magazine articles were a very good source of information and I picked up a lot from those but mostly it was about experimenting and teaching myself. The first machine code game I attempted was a terrible affair called Duel At Noon. A cowboy appeared on screen and the player had to press a button to shoot him, a bit like the duel sequence in The Wild Bunch but worse. It was all part of the learning process though. I still have one or two early titles. Aside from a respectable Centipede clone they were all pretty terrible before Egghead.



Egghead is probably your most successful gaming title – how does it feel to have made such a classic?

I don’t know about classic, I was just lucky to have written the game while the Spectrum was still popular. I was 18 and it’s a little primitive in a my-first-platform-game kind of way, but there are some fun level designs in there.


How many Egghead titles have you made and do you hope to launch any further titles in the series?

There are five in the series plus a couple of specials. The first two were written back in the day and the other three were written between 2002 and 2007. I may write a sixth title for the thirtieth anniversary in 2019; I certainly felt inspired to have another look at doing so when I saw Barnsley Badger released for the C64.


How easy or difficult is it to create a game on the ZX Spectrum?

That really depends on how you intend to create it. If your intention is to sit down with an assembler and you haven’t written a Spectrum game before it’s going to be very challenging. Assembly language programming takes some getting used to, every single task has to be broken down into the tiniest steps and it can take hundreds or thousands of instructions just to display a few words, play a sound or animate a sprite across a screen. Thankfully, there are easier ways to write Spectrum games nowadays.



Have you ever developed a video game on another platform apart from the ZX Spectrum?

A few have been converted to other platforms. Byte Me and Egghead in Space are available for Acorn machines and Area 51 has been converted to the CPC. They’re all excellent conversions too, by the likes of Chris Dewhurst and Kees Van Oss. The only development I’ve completed myself was an Amstrad CPC version of Arcade Game Designer.


How big is the current ZX Spectrum scene and are there many other people you know making games for the system?

There are thousands of people who dip in and out of the Spectrum scene, it’s very popular.  Dozens of new games are released for the machine every year and many of them are absolute corkers.



What is your favourite ever ZX Spectrum game and other games you loved playing?

That would be Halls of the Things. The graphics were terrible and there was no sound but that didn’t matter. It pulled the player in and wouldn’t let go once he was under its spell. Other fun games included Dictator, Rocket Raider and Escape from Krakatoa. I also had a lot of fun playing a little-known game called Catwalk, a very simple affair but very entertaining at the time.


If you could travel back in time and work on any video game, which game would you have loved to be involved in?

Knight Lore.  It truly shook the games world when it was released.



What gaming projects are you currently working on?

I’m currently working on a few bits and pieces for the forthcoming ZX Spectrum Next which is all very exciting. As part of that I’m hoping to develop a version of AGD for the machine. Of course, it’s a bit of a step up from the original Spectrum and I’m having to rethink the way I go about writing code for the machine.


If you could go for a drink with any video game character, who would you choose and why?

That’s a very good question. I reckon Rick Dangerous would have plenty of interesting stories to tell and of course Jet Set Willy always throws such wild parties over at his mansion, it would be fun to go to one of those.


Thanks Jonathan, we look forward to seeing what you come up with next! Readers, you can keep up to date with all of Jonathan’s goings on at his homepage or his download page over at



1 thought on “Jonathan Cauldwell (ZX Spectrum Dev) – Interview”

  1. Jonathan.
    I am looking for a software to create my own cassette inlays for my own new spectrum games for 48k.
    just asking if you of anything that will help.

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