WiFi-enabled ‘smart’ light bulbs are everywhere these days, and each one of them has a microcontroller inside that’s capable enough to run all sorts of interesting software. For example, [vimpo] decided to get one running a minimal Minecraft server.
Inside the target bulb is a BL602 MCU by Bouffalo Lab, that features not only a radio supporting 2.4 GHz WiFi and BLE 5, but also a single-core RISC-V CPU that runs at 192 MHz and is equipped with 276 kB of RAM and 128 kB flash.
This was plenty of space for the minimalist Minecraft server [vimpo] wrote several years ago. The project says it was designed for “machines with limited resources”, but you’ve still got to wonder if they ever thought it would end up running on a literal lightbulb at some point.
It should be noted, of course, that this is not the full Minecraft server, and it should only be used for smaller games like the demonstrated TNT run mini game.
Perhaps the next challenge will be to combine a large set of these light bulbs into a distributed computing cluster and run a full-fat Minecraft server? It seems like a waste to leave the BL602s and Espressif MCUs that are in these IoT devices condemned to a life of merely turning the lights on or off when we could have them do so much more.
Looks like a more advanced version of the Doom test…
How much does the light bulb cost?
9 out of 10 times when they brake the lihtbulb is fine, just the powersupply is burnt. you can still hook up 5/3.3v to the board and it might work just fine … i’d call that “free”
When they brake – how fast were they going ?
The speed of light?
it should last for years but it depends un usage and external factors; heat kills the electronics.
i had 4or5 smart lights burn out after maybe a year of use. on the other hand, ive had the exact same bulbs work for years in other fixtures.
i guess its a como of QC and heat dissipation.
one thing is certain, it was the little tansformer every time.
” It seems like a waste to leave the BL602s and Espressif MCUs that are in these IoT devices condemned to a life of merely turning the lights on or off when we could have them do so much more.”
Sound to like you are supposed to buy the bulb to save the MCU from a boring life instead of just buying the MCU?
Maybe that’s why some people run botnets on them? :)
How many engineers does it take to change it ?
With that much communications and compute horsepower this sounds like an ideal setup for a distributed LiFi-like broadcast setup.
Also a great plot element for an infiltration story.
That’s an interesting idea. Do the phosphors in white LEDs react fast enough to make that invisible?
On a related note I recently visited a restaurant that was mainly illuminated by strings of half wave rectified LEDs, made me feel nauseous before the food ever came.
I measured “normal” white (i.e. red+yellow) phosphors to have time constants in the 1-2 microsecond range, so they could support baud rates of 100 kHz. Actual bit rates might be 2-5x that, depending on coding complexity.
But the underlying blue LED can be modulated much faster, and even with relatively mundane drivers could support 10 Mbps outbound bandwidth, and the narrowband blue light would afford better SNR through filtering out other ambient light.
The return channel, if needed, could be a plain old near-infrared receiver. Bit rates vary with range, SNR, etc., but existing COTS solutions support everything from 4 Mbps to 9600 bps, or even longer range/poor SNR but slower solutions with IR remote-control signalling protocols.
Feels alott like bareiron for the esp32 https://hackaday.com/2025/09/13/esp32-hosts-functional-minecraft-server/ HaD earlier made a post about. maybe we can see a subcatagory for any platform we run minecraft servers on. First we had Pong, Doom, Crysis and now Minecraft but for really small systems. cool.