NES-OS: A Graphical Operating System for the NES

One of the most notable aspects of the NES console is that its hardware limitations did not prevent the development of memorable games. We should also remember the special case of Masahiro Sakurai, who created Kirby's Dream Land with a Famicom and a trackball, but today we come across an even more challenging project: NES-OS, an operating system specifically designed to run on the original NES configuration, with its gamepad as the input device.

Unlike what we can observe in modern consoles with gigantic firmware images and secondary functions, many platforms from the '80s and '90s did not have a preinstalled operating system. In relaxed terms, the cartridges themselves told the hardware what to do, and the process demanded efficiency for the simple reason that consoles didn't have much power under the hood.

The original NES was no exception. Although there were special environments like Family BASIC (which came with a keyboard compatible with the Zapper port), the amount of available RAM was not enough (2 KB for the CPU, and another 2 KB of VRAM) to allow more complex development. However, this did not stop Inkbox on YouTube, who created a new operating system for the NES called NES-OS.

NES-OS: A graphical operating system on the NES

The overall design of NES-OS is divided into two applications: a text processor and a settings menu. If the text processor were limited to the number of sprites allowed in the foreground, saved documents could not exceed 64 characters.

However, the NES also supports background sprites, and with smart use of that resource, the limit increases to 832 characters. The total of letters and symbols available for the processor is 64, and they work perfectly, regardless of whether we have access to the Family BASIC keyboard, or if we must type with the gamepad.

NES-OS: An Operating System for the Nintendo Entertainment System — The “desktop” of NES-OS, with a logo inspired by Nintendo's first design

Obviously, Inkbox cannot escape the RAM limits of the console, and for that reason he decided to limit the maximum size of each file to 832 bytes (832 characters, one full screen).

When saving files, Inkbox configured an NVRAM module with 8 KB (NES-OS is essentially a virtual cartridge), enough to save a total of eight files, and being non-volatile, the information is retained even with the console off (the old NES classics used a battery).

Finally, the settings menu also works as a kind of file manager, and includes technical data about the console, and the available memory.