Method for selectively activating and deactivating devices having same first address and different extended addresses

• US 4,918,598 A
• Filed: 12/14/1987
• Issued: 04/17/1990
• Est. Priority Date: 08/14/1985
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Apple Computer Incorporated (Apple Inc.)
• Inventors: Clark, Michael, Ashkin, Peter B.
• Primary Examiner(s): Lee, Thomas C.
• Application Number:
  US07/132,124
• Time in Patent Office: 855 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 364/137, 364/138, 364/514, 340/825.02, 340/825.03, 340/825.07, 340/825.52, 340/825.53, 370/85
• US Class Current: 710/3
• CPC Class Codes: G06F 12/0661 and decentralised selection
• CPC Class Codes: G06F 13/362 with centralised access control
• CPC Class Codes: G06F 13/376 using a contention resolving method, e.g. collision detection, collision avoidance
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04L 12/403 with centralised control, e.g. polling

Abstract

A method for activating one of a plurality of devices coupled to a communications medium at a first address location and controlled by a host computer. A plurality of extended addresses are provided to the devices, each of the devices having a unique extended address. A command is transmitted from the host computer to the first address. One of the plurality of devices is activated by transmitting the unique extended address of the device on the communications medium, the activated device responding to further commands sent to the first address location.

Claims

1. A method for transferring signals and data, wherein the signals and data are transferred under the control of a host computer between the host computer and first and second peripheral devices, wherein the signals and data are transferred over a bus coupling the first and second peripheral devices to the host computer, wherein the first and second peripheral devices are initially inactive, and wherein the first and second peripheral devices have a same first address, comprising the steps of:

the host computer initially activating the first peripheral device by transmitting over the bus (1) the first address of the first peripheral device and (2) a signal that matches a first number stored as an extended address of the first peripheral device, wherein the second peripheral device remains inactive;

after the first peripheral device is activated, the host computer sending a command over the bus to the first address of the first peripheral device, wherein the first peripheral device executes the command without the host computer sending the extended address of the first peripheral device, and wherein the second peripheral device remains inactive;

the host computer both activating the second peripheral device and deactivating the first peripheral device by transmitting over the bus a second number as an extended address, wherein the second number is the extended address of the second peripheral device, and wherein the second number is different from the first number;

after the second peripheral device is activated, the host computer sending a command over the bus to the first address of the second peripheral device, wherein the second peripheral device executes the command without the host computer sending the extended address of the second peripheral device, and wherein the first peripheral device remains inactive.

2. The method of claim 1 for transferring signals and data, wherein at least one of the first and second peripheral devices comprises an appliance.

3. The method of claim 1 for transferring signals and data, wherein at least one of the first and second peripheral devices comprises a system protection device.