Doombuds: "Doom" runs on wireless in-ear headphones

The list of devices on which "Doom" doesn't run has become a bit shorter again: A hobbyist with the username arin-s has managed to get the classic shooter running on wireless in-ear headphones.

Several tricks were necessary for the development of the "Doombuds", as arin-s writes on the project's website. Among other things, the memory hunger of "Doom" had to be reduced so that the game would fit into both the flash memory and the limited RAM of the headphones. Additionally, arin-s overclocked the CPU of the in-ears. The image is transmitted to an external computer via MJPEG stream.

Open-Source Earbuds

The "Doombuds" are the Pinebuds Pro, which were suitable for the project due to their open-source firmware. A port of "Doom" runs on the earbuds, which in the "Squashware" version only occupies 1.7 MB of storage space – the original shareware is 4.2 MB and would have narrowly exceeded the flash capacity of the earbuds.

Arin-s was able to reduce the RAM of the Pinebuds Pro to 992 KB. Normally, this would not be enough for "Doom" because the game requires 4 MB. However, hobbyist arin-s managed to sufficiently reduce the RAM requirements with optimizations to the "Doom" code. For example, he predefined lookup tables (LUT) and removed unnecessary variables.

Finally, arin-s overclocked the CPU integrated into the earbuds to 300 MHz. This is just enough to play "Doom" at 18 frames per second and to realize the MJPEG encoding. The compressed image is sent via the serial UART interface to an external computer. The UART interface is usually used for debugging the headphones, but according to arin-s, it is better suited for this data transfer than Bluetooth. It also receives input from the computer, allowing the Doom Guy to be controlled.

Remote Play on Twitch

Arin-s decided to stream the game via Twitch. On his website, you can join a waiting list to play on the hacked in-ears yourself via remote play. Due to 18 FPS and input lag, this is at least a playable experience that can be improved. Those who wish can also download the "Doom" port optimized for the Pinebuds Pro and associated software and start playing with their own Pinebuds.

The porting of "Doom", released in 1993, is a running gag in the hobbyist scene: programmers and hackers challenge themselves to get the shooter running on as many platforms and objects as possible. These include calculators, toothbrushes, and lawnmowers, but also the PDF file format.

(dahe)