YouTuber and hardware enthusiast RetroMorten has successfully ported the classic 1993 first-person shooter DOOM to a 1990s-era Japanese electronic organizer, the Casio Ruuvi, which features a built-in thermal printer. This modification allows the device to render the game’s 3D environments on a low-resolution screen and physically print gameplay snapshots or data via the integrated receipt printer.
The project is part of a long-standing internet phenomenon known as “Can it run DOOM?”, where developers attempt to port the id Software title to increasingly improbable hardware. By leveraging the limited processing power of the Casio device, RetroMorten demonstrated that the game’s engine could function on a machine never intended for gaming, provided the software is sufficiently optimized for the hardware’s constraints.
The Casio Ruuvi, a niche piece of 90s Japanese tech, was designed for business productivity and note-taking. Its primary hardware feature—the thermal printer—was originally intended for printing memos and lists. In this new configuration, the printer serves as a physical output for the game, bridging the gap between digital software and analog paper.
Technical Hurdles of the Casio Ruuvi Port
Porting DOOM to a device like the Casio Ruuvi requires significant modifications to how the game handles graphics and memory. According to RetroMorten’s documentation and video demonstration, the hardware lacks the traditional GPU power found in PCs or consoles of the era. To make the game playable, the developer had to work within the strict limitations of the device’s CPU and limited RAM.
The rendering process on the Ruuvi is considerably slower than on original 1993 hardware. The screen’s low resolution and monochrome or limited-color palette mean that the visual fidelity is stripped down to the bare essentials. However, the core mechanics—movement, combat, and map navigation—remain intact, proving that the game’s logic can be decoupled from high-end graphics requirements.
A critical component of this specific port is the integration of the thermal printer. Rather than simply playing the game on the screen, RetroMorten configured the system to send data to the printer. This allows the user to generate a physical “receipt” of their progress or a low-fidelity image of the current game frame, a feat that requires translating the game’s pixel data into the specific command language used by Casio’s thermal printing hardware.
The Legacy of “Can it run DOOM?”
The drive to port DOOM stems from the 1997 release of the game’s source code by id Software. Because the code is open and highly portable, it has become the gold standard for testing the limits of embedded systems. This project follows a lineage of ports to unexpected devices, including digital cameras, pregnancy tests, and even smart refrigerators.
The Casio Ruuvi project adds a layer of tactile interaction that is rare in the “Can it run DOOM?” community. While most ports focus on whether a screen can display the image, the use of a thermal printer introduces a physical artifact of the gaming experience. This intersection of retro-computing and “junk” hardware is a central theme in the modern maker movement, where the goal is often the challenge of the port rather than the practicality of the gameplay.
For those interested in the technical specifics, the project highlights the efficiency of the original DOOM engine. The game’s use of binary space partitioning (BSP) allowed it to run on hardware that would today be considered negligible, making it the ideal candidate for these experimental ports.
Hardware Specifications and Impact
The Casio Ruuvi represents a specific era of Japanese “pocket” electronics that prioritized utility over entertainment. By forcing a high-action game onto a device meant for accounting and scheduling, RetroMorten highlights the versatility of C-based programming and the longevity of 90s software architecture.
The impact of such projects is primarily educational and artistic. They demonstrate to new developers how to optimize code for extremely constrained environments—a skill that remains relevant in the development of IoT (Internet of Things) devices and embedded sensors where memory and power are limited.
The physical output of the thermal printer also serves as a commentary on the evolution of media. Moving from a digital screen to a thermal printout reverses the trend of digitalization, returning the gaming experience to a physical, disposable medium reminiscent of 20th-century office technology.
As the community continues to seek out obscure hardware, the focus is shifting toward “multi-modal” ports—where the hardware’s unique physical traits (like printers, LEDs, or haptic motors) are integrated into the game’s logic. The Casio Ruuvi port is a prime example of this evolution.
Further updates on the project’s code and potential open-sourcing of the port are expected to be shared via RetroMorten’s social channels and video repository. Those interested in attempting similar ports can find the original DOOM source code available via GitHub, which remains the primary resource for these hardware experiments.
Do you have a piece of ancient tech that deserves a DOOM port? Share your thoughts in the comments below and let us know which obsolete gadget we should track next.
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