Convert that Old VTech “Toy” Computer Into a Z80 Hacking Station
This guide from Bernhard “HotKey” Slawik explains how you can use an old VTech "PreComputer" as a Zilog Z80 hacking station.
As a child of the ‘90s with a deep love of computers, I’ve always felt somewhat antagonistic towards VTech and their silly toys disguised as computers. In my mind, they were really just glorified pocket calculators. That is mostly true, but they did have some cool hardware inside and this guide from Bernhard “HotKey” Slawik explains how you can use that to create a pretty nifty Z80 hacking station.
The Zilog Z80 is, of course, the quintessential microprocessor of the 8-bit era (don’t come at me, 8080 fanboys). The Z80 was in everything from the iconic Sinclair ZX Spectrum to professional Kaypro machines. Even the Sega Game Gear has a Z80. And yes, calculators like the ubiquitous TI-83 had Z80 processors, too.
The Z80 was cheap and it was everywhere, including in several of Vtech’s PreComputer models. The ROM in those models was extremely limiting, which is why I — and everyone else, I assume — hated them. But now you can boot from whatever ROM you want to open up the true potential and that is exactly what HotKey’s guide focuses on.
HotKey provides a lot of information on the subject that you can peruse at your leisure, but the basic idea is to load a custom ROM to do whatever it is you want to do. You can even load a ROM from a DIY cartridge to boot on an unmodified PreComputer. Once you have that access, you can do things like bit-bang the printer port to use it as a 9600-baud serial port for data transfer.
Why would you want to do any of this? Well, it is an absurdly affordable way to play around with a Z80 and not risk damaging a system that the retrocomputing community actually cares about. You can even run some games from the Sierra AGI (Adventure Game Interpreter) catalog, like Space Quest II and King’s Quest. Though, admittedly, you can’t run the full games and the bits you can run are glitchy and somewhat compromised.
The point is that those old VTech toy computers aren’t quite as useless and uninteresting as they once seemed. But I can hold a grudge and still don’t forgive VTech for trying to trick me into thinking these were real computers when I was a kid.