Abstract: Master units and slave units are preferably housed in identical housings. Each master unit comprises a Central Intelligence Unit (CIU) which in turn comprises a drum processor and a communications processor, and an Input/Output Unit (IOU) having input terminals and relays for connection to external devices. Each slave unit comprises an IOU. Each IOU is connected to its CIU through a Local bus (L-bus). Up to sixteen IOU's may be controlled by a single CIU.Up to 16 master units may be connected together by means of console bus (C-bus) and a data exchange bus (X-bus), in which case each master unit is given control of specified "X" variables for update. Each "X" variable has a specific time slot on the X-bus and all "X" variables are stored on an X-drum at each master unit.The C-bus may be connected to a computer terminal at each master for programming of all CIU's, or to computer devices, or to long distance communication lines.

Abstract: A programmable sequence controller is disclosed utilizing digital and analog inputs in order to generate digital output driver signals for the control of external systems or devices. The controller emulates mechanical sequence drums so that at any one time each of the simulated drums within the controller executes one of the addressable drum lines programmed within the drum. Each line of each simulated drum can be programmed to specify the energization or deenergization of any output driver as well as the energization or de-energization of any memory bit utilized by the controller in order to provide communication between drums. Each drum may also be programmed to have one or two sets of exit conditions, which if met, cause the controller to effectively rotate the drum to a specified drum line and execute this new drum line during the next scan of the controller.