Abstract: An in-flight passenger entertainment system has a first digital network for communication among components of a headend system including a data server, media controller, one or more media servers, system interface unit, system manager unit and attendant control panel. The in-flight entertainment system is coupled to an aircraft's existing systems through the system interface unit and the system manager unit. The components of the headend system are all coupled to a network switch for routing data within the first network. The network switch is also coupled to one or more zone bridge units, each of which is coupled to multiple seat electronics units. The zone bridge units and the seat electronics units together form a second digital network. The first digital network is preferably an ATM network with fibre optic cables used to carry the data. The second digital network is preferably an IEEE 1394 serial bus network.

Abstract: A technique and system for isolating segments of a serial data bus for remote configuration of equipment in in-flight entertainment systems. The system allows the automatic initialization, or configuration, of multiple terminal units, attached to a serial data bus, without requiring physical access to the multiple units.

Abstract: A boundary scan analog signal test circuit for boundary scan testing of analog signals. The boundary scan analog signal test circuit provides for known upper and lower bound values at specified times for testing whether sample analog signals are within the specified lower and upper bound values. If the sample analog signals are not between the known upper and lower bound values, the boundary scan analog signal test circuit produces a result flag indicating a "not pass" for the device being tested. If the sample analog signal being tested is found to be within the known upper and lower bound values, then the circuit generates a result flag indicating that the device being tested has passed the test.

Abstract: The interrupt regenerator circuit converts the transition signal caused by a passenger's data entry in an aircraft entertainment system into a triggering signal. The triggering signal triggers a delay element consisting of cascadable one-shot devices. The timing intervals for the outputs of these one-shot devices are programmable through the selection of proper values for the resistors and capacitors. The interrupt signal is de-asserted by the host processor when the host processor responds to the interrupt. The delayed interrupt signal is then gated by the interrupt signal itself to regenerate the interrupt signal to the host processor.