RetroChallenge 2022/10 – Project aims

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My aim: A re-implementation from scratch of “The Valley“, as published in Computing Today magazine, April 1982. I originally started working on this during August, but the project has fallen by the wayside since. The RetroChallenge seems an ideal opportunity to start this project again. No cheating – everything will be / has been typed in by me (and debugged!), just as I did in 1982 on my Sharp MZ-80K.

The Valley - Swamp scene on the Sharp MZ-80K
The Valley – Swamp scene on the Sharp MZ-80K version I created back in 1982.

Target hardware: The Compukit UK101. As far as I’m aware no implementation of The Valley exists (or if one did exist, survives) for the UK101. My first step will be to use the FPGA Compukit UK101 I built in August 2022, with the CEGMON monitor configured for a screen resolution of 64×32 characters.

My stretch goal will be to see if I can make a subset of the game work on my real Compukit UK101. It will need to be a subset of the game as it has just the “standard” 8K RAM (and the game as written requires over 20K).

This will be much more difficult as I will need to repair the cassette interface on it first, and probably some other things that have broken or degraded in storage over the last decade or so since I last used it. I also don’t have CEGMON for my real machine – just the original monitor as supplied with the kit back in 1979/80. This will severely constrain the screen resolution I can use, and probably create some other challenges too …

Because of these issues I intend to reconfigure my FPGA version to exactly mimic my real hardware first, before getting my soldering iron out … October looks as if it will be busy!