sample when an enabled change is detected an interrupt is generated the actual bus signal conditions are compared with desired bus signal conditions once coincidence between the actual and desired conditions is achieved a recipe process is executed application_number US 94465386 A description the present invention may have general applicability to other imaging systems and to systems other than imaging systems the following disclosure should be thus regarded for concreteness however the description herein is given in the environment of an x ray imaging system it should also be clear that the term imaging system should be given its broadest interpretation referring now to fig1 there is shown generally at 10 an x ray imaging system in accordance with an embodiment of the invention an x ray generator 12 includes a conventional x ray tube 14 whose filament power is controlled by a filament controller 16 as indicated by a line 18 a cathode voltage of x ray tube 14 is controlled by a high voltage power unit 20 as indicated by a line 22 an x ray receptor and patient positioner 24 receives the x rays from x ray generator 12 after they have been modified by a body not shown about which the x ray process is intended to produce information an exposure control module 26 controls all functions in x ray generator 12 and some functions in x ray receptor and patient positioner 24 as indicated by line 28 30 32 and 34 connected from exposure control module 26 to filament controller 16 high voltage power unit 20 x ray tube 14 and x ray receptor and patient positioner 24 respectively in addition data responsive to conditions in.