C ONT ROLLER bbM EN U 1 . T I MING bbD AT A 6 . S TART FLASH bbD AT A 2 . P H O V LP bbA SS I G N 7 . N O S ER V E P HAS ES bb3 . P ED bbC ARR YO V ER bb8 . D I MM ING bb4 . R EC ALL bbD AT A 9 . O PT ION bbD AT A 5 . O V ER LAP bbD AT A P RES S K E Y S 1 . . 9 T O S ELECT bbFbbbbH E LP bbP ILL AR bbC AMER A C ONT ROLLER bbC AMER A # 4 P RESET bbC AMP OS bbK E Y C OM MAN D P AN bb + / - 1 8 0 . 0 ] + 1 0 4 . 6 - 1 0 5 . 8 [ LR bbA RR OW ] T IL T [ + / - 9 0 . 0 ] - 3 5 . 7 - 4 5 . 4 [ U / D A RR OW ] Z O OM bb 0 - 8 0 0 0 ] 2 0 0 0 1 0 0 0 [ + O R - ] [ * G O T O P RESET ] [ NEXT ] [ * T O P RESET ] [ ES C T O S ET bb0 , 0 , 0 ] R AD IA TI ON bbD ET EC TI ON bbT I ME bb0 5 : 1 8 U NIT # 0 1 S TAT US bbL O G T EST bbV EH bbP RES : Y V EH bbR AD : 0 . 0 0 A LA RM bbT HRS H : 1 . 0 0 m Rh r V EH bbS PD : 3 7 A LE RT bbT HRS H : 0 . 0 5 m Rh r V EH bbC NT : 4 8 V EH bbC NT bbL O G : 2 0 3 1 9 5 8 [ MORE ] Figure 3. Example user interfaces for three programs on a single controller unit using the ATC API Front Panel Manager (only one screen displays at a time. For the programs in a traffic controller to be able to interact with a device outside of the cabinet, there must be a connection between the controller and that device. Typically, this is done through afield IO interface between the controller and cabinet. All of the major transportation cabinet architectures in use today have a similar concept of inputs (usually detectors) and outputs usually load switches) addressable as points or pins to a single program in the controller. The API Standard expands this concept via the API Field IO Manager by allowing all currently running programs to read all IO points available to the controller but require an exclusive assignment of an output point to a single program. Figure 4 illustrates an ITS Cabinet with three programs with each program assigned to different load switches in the cabinet. The API simplifies field IO functions by providing a single common internal software interface for all of the current cabinet architectures including the Caltrans Model 332 Cabinets, NEMA TS 1 and TS 2 Cabinets, and ITS Cabinets. This allows software developers to write their application programs in a consistent manner regardless of the target cabinet architecture. Page 5 of 9