Pathway DMX Pathfinder CR Manual - Manual (Page 39)

DMX Distribution System Page 39
DMXPathfinder - Hardware
.6 SYSTEM COM BUS and I/O BUS
In multi-frame systems, there are two sets of 40-conductor twisted-pair
ribbon cables linking all of the frames. The system COM bus and system I/O
bus run on these cables. The system COM bus provides for inter-frame
communications of command, status and patch file data between the Master
Control Module and each of the Frame Control Modules, and the system I/O
bus carries actual DMX send and return data between all of the frames in the
system. The cable connected to P9 on the backplane board of each frame
carries both the system COM bus and the 16 DMX send (output data) lines.
The cable connected to P10 on the backplane board of each frame carries
the 16 DMX return (input data) lines.