What Protocol does ProMotion or Sunny use to communicate to a display?
The protocol used to communicate information between the software and the display is a custom protocol created for the original sign company (AOPAC). As the internet protocols were not widely used when this system was designed, it is not directly compatible with any modern data communications network protocols without using some type of thin-server to provide an IP wrapper. The display protocol data contains graphical data represented in hexadecimal format, which could randomly take the form of X-ON and X-OFF commands, or frame characters. Any communications devices or drivers that the user installs to provide connectivity needs to be able to handle these special characters without stripping them out, altering them, or crashing.
