04251865 is referenced by 81 patents and cites 8 patents.

Channel efficiency in a communications link between a controller and multiple portable units is increased by polling the active units and a set number of inactive units in a sequence where a "poll" consists of sending the binary coded address of the portable unit. The stream of transmitted data bits is only interrupted by a response from the portable unit, then resumed at the end of the response or a given portion of the response. During the reception of the response, certain other types of messages can be sent out by the controller. Portable responses can be automatic responses as to status, etc., or can be data initiated by the operator of the portable unit keyboard and stored in the portable unit memory until "armed" by the operator, then automatically transmitted to the controller when the portable unit address is received.

Title
Polling system for a duplex communications link
Application Number
5/968066
Publication Number
4251865
Application Date
December 8, 1978
Publication Date
February 17, 1981
Inventor
Robert H Bass
Sunrise
FL, US
Morris A Moore
Sunrise
FL, US
Agent
James W Gillman
Margaret Marsh Parker
Assignee
Motorola
IL, US
IPC
H04Q 5/00
H04J 6/00
G06F 3/04
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