Abstract: A method and apparatus in a client processing system are provided for characterizing an input television signal as broadcast television or cable television and, if the signal is cable television, as IRC cable, HRC cable, or standard cable. The client processing system includes processing circuitry configured to receive hypertext pages from a remote server and to display the hypertext pages on a display device, such as a conventional television set. The client system further includes a television tuner for receiving either cable television or broadcast television signals. When a television signal is initially provided to the client system, the client system executes a routine to automatically characterize the received television signal as broadcast, HRC cable, IRC cable, or standard cable. The characterization is made based upon one or more frequencies at which the incoming television signal is detected.

Abstract: A method for presenting help messages to a user in an interactive computer environment in which a help mode operates concurrently with other programs operating in the computer system. The user receives information about an icon by positioning a pointer on the computer's video display over the icon about which more information is desired. The computer then retrieves an appropriate help message based upon user sophistication from a database of help messages stored in its memory and displays it in a graphic bubble on the video display. The graphic bubble is placed so as to not overlap the object about which more help is requested. The graphic bubble is removed as soon as the pointer is moved away from the object.

Abstract: A local area network is disclosed including apparatus and methods for transferring data between a plurality of data processing resources ("agents") coupled to a cable. In the preferred embodiment, a plurality of agents are coupled to a common cable for data transmission and reception. An agent newly coupled to the cable dynamically assigns itself a unique address on the cable to which other agents may send data. Once an agent has been assigned a final address, it may then transmit to, and receive data from, other agents on the cable. An agent desiring to send data to a receiving agent follows a three step handshake, wherein the sending agent transmits an "RTS" signal and within a predetermined time must receive a "CTS" signal from the receiving agent. The sending agent then transmits a data frame within a predetermined time after the CTS signal is received. The failure to detect a return CTS signal within the predetermined time denotes a collision condition.

Abstract: A local area network is disclosed including apparatus and methods for transferring data between a plurality of data processing resources ("agents") coupled to a cable. In the preferred embodiment, a plurality of agents are coupled to a common cable for data transmission and reception. An agent newly coupled to the cable dynamically assigns itself a unique address on the cable to which other agents may send data. Once an agent has been assigned a final address, it may then transmit to, and receive data from, other agents on the cable. An agent desiring to send data to a receiving agent follows a three step handshake, wherein the sending agent transmits an "RTS" signal and within a predetermined time must receive a "CTS"signal from the receiving agent. The sending agent then transmits a data frame within a predetermined time after the CTS signal is received. The failure to detect a return CTS signal within the predetermined time denotes a collision condition.