Abstract: A system comprising an interface module (IM) for receiving input and generating outputs, the IM being associated with processor (17) and memory (19); a controller module (18) (CM) that is operable independently of and communicatively connected to the IM and that is associated with processor (20) and memory (22) and that receives inputs and generates outputs to control accessories wherein each memory stores a copy of a parameter list (38) and rules governing generation of the outputs, wherein each of the IM and CM is configured such that responsive to each input, the processor of the respective module IM, CM defines a state in the associated copy of the list and communicates with the other module IM, CM to cause the state to be defined in the other copy, wherein each rule requires a state to be present in the list for generation of an associated output by each module.

Abstract: A system comprising an interface module (IM) for receiving input and generating outputs, the IM being associated with processor (17) and memory (19); a controller module (18) (CM) that is operable independently of and communicatively connected to the IM and that is associated with processor (20) and memory (22) and that receives inputs and generates outputs to control accessories wherein each memory stores a copy of a parameter list (38) and rules governing generation of the outputs, wherein each of the IM and CM is configured such that responsive to each input, the processor of the respective module IM, CM defines a state in the associated copy of the list and communicates with the other module IM, CM to cause the state to be defined in the other copy, wherein each rule requires a state to be present in the list for generation of an associated output by each module.