Auto address and configuration of a multi-drop communication system including automatic termination of same
View Patent ↗The application of this method is an addressable lighting control system using the In Seat Power Supply as an interface between the passenger control device for lighting and the aircraft Cabin Services System. On wide body aircraft, there does not exist a system to control the reading and attendant call lights without installing a complete In Flight Entertainment system. This is a part of the system used to communicate from a passenger interface to the lighting system based on location of the passenger in the aircraft. This invention decreases the weight and complexity of other communication and addressing schemes used on-board aircraft as well as obviating the need for termination plugs or jumpers at the end of the multi-drop communication line.
1. A system to address and locate a device on a multi-drop bus structure without the use of a token signal, comprising:
a first master unit in communication with a cabin service server and with one or more second master units, each master unit further including a database mapping an expected configuration of seat devices and associated passenger control units;
the cabin service server in communication with one or more passenger service modules, each passenger service module electrically controlling one or more electrical devices;
the first master unit and each second master unit in communication with a separate zone of the seat devices, each seat device in communication with one or more of the passenger control units;
wherein toggling a switch on a particular passenger control unit is associated with a change in status of a particular one of the electrical devices; and
wherein each master unit assigns an address to each seat device in its zone and forwards those addresses to the cabin service server and the cabin service server matches each seat device address to a passenger service unit.
2. The system of claim 1 wherein when there are more than one second master unit, they are electrically interconnected by a daisy chain.
3. The system of claim 2 wherein each seat device includes a relay.
4. The system of claim 3 wherein when said relay is open, either the seat device does not have an assigned address or the seat device is defective.
5. The system of claim 3 wherein when said relay is closed, said master unit is in communication with the next seat device in the zone.
6. The system of claim 5 wherein there is an automatic termination of the addressing when the last seat devices in a zone has been assigned an address.
7. A method to address and locate a device on a multi-drop bus structure without the use of a token signal, comprising:
providing a first master unit in communication with a cabin service server and with one or more second master units, each master unit further including a database mapping an expected configuration of seat devices and associated passenger control units;
the cabin service server communicating with one or more passenger service modules, each passenger service module electrically controlling one or more electrical devices;
the first master unit and each second master unit communicating with a separate zone of the seat devices, each seat device communicating with one or more of the passenger control units;
wherein toggling a switch on a particular passenger control unit is associated with a change in status of a particular one of the electrical devices; and
wherein each master unit assigns an address to each seat device in its zone and forwards those addresses to the cabin service server and the cabin service server matches each seat device address to a passenger service unit.
8. The method of claim 7 wherein following addressing, each master unit initiates a status request from a first seat device in a zone.
9. The method of claim 8 wherein a status change by a particular seat device causes a particular electrical device to change status.
10. The method of claim 9 including selecting said particular electrical device to be a light associated with a seat in a cabin of a passenger aircraft.
11. The method of claim 8 wherein after polling a seat device in the zone, the next subsequent seat device in the same zone is polled for a status change.
12. The method of claim 11 wherein polling terminates when the last seat device in a zone is polled for a status change.