System for controlling television and billing for its use

Abstract

A billing system for billing for the use of television sets in a hospital, hotel or the like includes a computer located in a billing office and television sets located in various rooms. Command signals from the computer, video signals, and power for powering the television are all delivered to each television set over a single coaxial cable. Each television set includes a microprocessor, a modem and logic circuits which remain active even if a user turns off his television receiver. The computer may assume control over any one or more of the television receivers by issuing a slave command which, at a time specified in the command (1) turns an addressed television receiver on if it is off and (2) tunes the addressed receiver to a specific channel. The slave commands may be of two types. One type permits no control over the TV receiver by a user and the other permits a user to override the slave command. Billing for TV usage is stored in the TV set and is transferred to the computer in response to a command from the computer. Billing information in one TV set may be transferred to another set if a user should move from one room to another. In a second embodiment, power is provided from a conventional AC wall outlet but in this case the slave commands are not executed if the television receiver is unplugged.