Ingenious Developer Fits Solitaire Game on Single Nintendo GBA e-Reader Card

Independent game developer Matt Greer has recently shared an exciting project through a blog post and YouTube video where he successfully fit a complete game of Solitaire onto a custom Nintendo e-Reader card. This card is equipped with two “dotstrips,” each holding 2,192 bytes, making a total of just over 4.3 kilobytes of data.

For a bit of context, the Nintendo e-Reader was an accessory for the Game Boy Advance, launched in December 2001 in Japan and in September 2002 in the US. This device allowed users to scan cards to load full games or add-ons to existing Game Boy Advance games, storing them in the e-Reader’s substantial 8MB of internal memory. Some NES ports required up to 10 cards, and the e-Reader could support a maximum of 12. In contrast, other enhancements, like the additional levels in Super Mario Advance 4, needed just one card.

Greer’s blog goes into impressive detail, describing the journey of creating a homebrew Solitaire game for the Game Boy Advance under some of the most stringent constraints in gaming history. Creating homebrew games for the Game Boy Advance is already a niche interest, but condensing a Solitaire game into a single e-Reader card takes that niche to a whole new level.

According to Greer’s blog, the e-Reader can load NES games, raw binaries, and even Zilog Z80 binaries. Z80 assembly, with its minimal footprint, proved particularly beneficial for this project. e-Reader applications can utilize an API that allows developers to leverage many common functions, reducing the need for repeated code in the dotstrips, which frees up space.

Greer also points out that the Z80 emulator within the Nintendo e-Reader has its limitations. It isn’t entirely accurate and operates with a restricted set of opcodes and registers, meaning some typical Z80 functionalities are not feasible on the e-Reader. Yet, even with these limitations, Matt Greer managed to create a fully operational game of Solitaire, complete with changeable music, all within just 4,384 bytes across two dot strips on a single custom card. It’s a remarkable feat, demonstrating the creative potential of homebrew developers. Sadly, due to the brief production period of e-Reader cards, the Nintendo e-Reader has mostly faded into obscurity.