Using Artnet DMX and the ESP32 to Drive Pixels
Englandsaurus 
DMX - No, not the rapper!
Before we start controlling lights, let's learn a little bit about how DMX works. DMX512 is a standard digital communication ecosystem typically used for stage lighting. It is primarily used to link lighting controllers to dimmable lights, fog, moving projectors and my personal favorite, laser beams. The hardware and data structure used to interface between DMX controllers and fixtures can be changed to fit the various applications of DMX.
Hardware
DMX fixtures can employ multiple hardware solutions for communication. The most common of these is the XLR 5-pin connector. However, you can also use an RJ-45 connector to send DMX data. Both cabling solutions take advantage of differential signaling using EIA-485 Voltage Levels. Wikipedia has a great summary of various DMX cable pinouts. For the purposes of my experiment, I'm sending data to a WiFi enabled DMX fixture, so I'll need neither of these cables.
Data Protocol
A DMX512 network, or DMX Universe can be comprised of many separate DMX fixtures (Fog machines, intelligent lights, etc...) all daisy chained together. The DMX controller will send a frame of data down this line. This frame consists of a break and subsequent mark to signal that a new frame has begun. The controller then sends out slot 0, which contains a one byte start code. Once all of the fixtures in our DMX Universe see this, the controller sends 512 slots of data (called channels), each containing a byte. To create an RGB color, a channel is required for red, green, and blue. This means that the number of individually addressable pixels that can be controlled in a single DMX Universe is 170.