When you’re connecting hardware to a network, it can sometimes be a pain to figure out which IP address the device ended up with. [Bas Pijls] I have seen this problem occur frequently in the classroom, and decided to create a simple method for small devices to communicate their IP address and other data with minimal hassle.
[Bas] Specifically wanted a way to do this without adding a display to the hardware, as this would add a lot of complexity and expense to ordinary IoT devices. Instead, RGBeacon was created, where a microcontroller flashes network data with a single RGB WS2812B LED.
In fact, all three colors of the RGB LED are used to send data to a computer via a webcam. The red channel represents a clock signal, the green channel represents the beginning of a byte, and the blue channel flashes to indicate higher bits. With a little bit of signal processing, a computer running a JavaScript application in a web browser can receive data from a microcontroller by flashing its LED through a webcam.
This is a neat hack that requires devices to be set up [Bas]Its classes are much easier. It does not need to be limited to network information; The code can be reused to allow a microcontroller to flash other messages as well. This is no different from the old Timex Datalink watch which uses monitor flash for communication!