Selection and Placement of PI units

Units must be close to equipment they connect to, because this simplifies wiring. You must allocate units with suitable configurations near those equipment. For example, if your are implementing a Production Tally System, a unit with just GPOs would be placed near the camera CCUs, a similar one near tally-capable video monitors or multiviewers, and some units with just GPIs near the Production Video Switcher.

Units might be scattered among the facility but the GPIO wiring will be short and simple this way. From each unit, a serial cable connects to the serial BUS.