Gheo Electronics,Tinkerkit DMX Master Shield The TinkerKit! DMX Master Shield is used to drive a series of DMX receivers. In order to be programmed via Arduino, it requires the DMX Library Like a regular shield it has to be plugged on top of the Arduino and it can be stacked on top of other shields. It is used both as OUTPUT and INPUT (also if the official library at the moment supports only the OUTPUT communication). For each line it has two kinds of port that can be used: the DMX connector or normal pins. On the front it has two DMX connectors, one for the INPUT and one for the OUTPUT. On the back it has one INPUT and one OUTPUT cable connector, each one divided in GND, D+ and D- . The DMX Master Shield supports up to 512 DMX modules connected in parallel. If you're using the TinkerKit! official receivers, they have four channels each that makes a total of 128 cascade connected modules, directly controllable from your computer.