Abstract: A controller for a video matrix switching system may include at least a first multiple purpose unit (MPU) module configured to provide video and control for a multi-camera video CCTV system, and at least a first port module connectable to the MPU module and having driver electronics for a set of interface ports. In some, but not necessarily all embodiments, the interface ports may include both a plurality of communications ports and one or more data line ports. Also, the MPU module may include a watchdog module configured to present an interface that monitors specified tasks and takes action when any of the specified tasks time out.