A Dandy Storage Solution for the ZX Spectrum

The ZX Spectrum computer holds a special place in the history of home computing, known for its affordability, versatility, and vibrant game development scene. Developed by Sinclair Research and released in 1982, the ZX Spectrum quickly gained popularity in the United Kingdom and beyond. It featured an 8-bit processor, a chiclet keyboard, and a sleek, compact design. Despite its modest hardware specifications, the ZX Spectrum boasted an impressive library of games and applications, making it a beloved platform for both gaming enthusiasts and aspiring programmers.

What makes the ZX Spectrum truly remarkable is the thriving community of enthusiasts that continues to expand and support the computer to this day. Decades after its initial release, a dedicated community of fans, developers, and hardware tinkerers continues to breathe new life into the ZX Spectrum. They create new games, develop emulators, and modify the hardware to enhance its capabilities.

If you want to load data onto a ZX Spectrum, the primary means is via a cassette tape drive. While this method was cost-effective at the time, it had its fair share of problems. Loading data from cassette tapes was notoriously slow, often requiring several minutes for a single game to load. Furthermore, cassette tapes were prone to errors and could be easily corrupted, leading to frustrating loading failures. Users had to patiently wait and hope that the data would load successfully, sometimes requiring multiple attempts.

Retro computing enthusiasts certainly appreciate original hardware, but in some cases, it just makes sense to sneak in some more modern technology. Tape drives were more of a necessary evil at the time than a beloved storage device anyway, so why not ditch them for a better option? And better options there are, like the ZX Dandanator! Mini that plugs into the computer’s expansion port to provide 512 KB of flash memory storage for instant loading of your favorite games and other software.

The ZX Dandanator! Mini is very much a DIY kit, however, and Richard Körber found the existing documentation to be a little bit lacking. So he decided to blog about building his own to help anyone else that is having difficulties making their own.

Körber first lays out the bill of materials, with some added links for the harder to find parts. He then begins a walkthrough of the assembly process with lots of photos and helpful tips to help you avoid any gotchas. One item that was called out in particular was getting the edge connector attached correctly. Whereas these connectors are normally attached upright, this project calls for them to be attached to the edge of the PCB. It takes a bit of work, bending pins and such, to get everything aligned for proper function.

It is also noted that the GALs called for in the project do not have internal pull-up resistors at the inputs. As a result, if you do not have an optional joystick plugged into the ZX Dandanator! Mini, you will get undefined behavior, like random programs automatically loading before you have a chance to make a choice. These resistors can be added to the build, and Körber details where they should be added.

You also want to be on the lookout for any short circuits that were inadvertently created during assembly before plugging the board into a real ZX Spectrum — failure to do so could cause damage to the power converter inside the computer.

Finally, the write-up walks through flashing the PIC microcontroller, GAL chip, and the flash ROM. And once you have everything ready to go, Körber provides links to some resources where you can download some classic games for use with the new storage device. Happy retro gaming!