Electrical computers and digital data processing systems: input/ – Intrasystem connection – Bus expansion or extension
Reexamination Certificate
2006-05-09
2006-05-09
Perveen, Rehana (Department: 2112)
Electrical computers and digital data processing systems: input/
Intrasystem connection
Bus expansion or extension
C710S304000, C710S260000
Reexamination Certificate
active
07043587
ABSTRACT:
A method and system for controlling the addition of a USB device to a host computer system via a hardware hot plug detector that monitors USB ports. The differential signal lines connecting to the USB device are logically OR'ed together, such that logically high D+ or D− signals from the USB device signal a central processing unit's (CPU) system management interrupt (SMI) line to initiate system management mode (SMM). Entering SMM transfers control of the host computer system to an SMI Interrupt Handler BIOS, which resides in the SMM address space of the hose computer system. The SMM BIOS is loaded into the SMM address space during Power On Self Test (POST) and is secured prior to booting the Operating System (OS). The SMM BIOS code contains instructions as to whether or not the connected USB device should be made visible to the operating system of the computer. If the device is not authorized, it is disabled, the D+/D− lines are not connected to the USB host controller, and the SMI signal is cleared, allowing the computer to continue operation without the operating system ever being aware of the USB device.
REFERENCES:
patent: 5406260 (1995-04-01), Cummings et al.
patent: 5796984 (1998-08-01), Pearce et al.
patent: 5821870 (1998-10-01), Jackson, Jr.
patent: 5854891 (1998-12-01), Postlewaite
patent: 5926091 (1999-07-01), Svensson et al.
patent: 5944840 (1999-08-01), Lever
patent: 6029248 (2000-02-01), Clee et al.
patent: 6064305 (2000-05-01), Lockyer
patent: 6098171 (2000-08-01), Johnson et al.
patent: 6104289 (2000-08-01), Rand
patent: 6128732 (2000-10-01), Chaiken
patent: 6131134 (2000-10-01), Huang et al.
patent: 6138240 (2000-10-01), Tran et al.
patent: 6147603 (2000-11-01), Rand
patent: 6172606 (2001-01-01), Lockyer
patent: 6205502 (2001-03-01), Endo et al.
patent: 6216183 (2001-04-01), Rawlins
patent: 6233640 (2001-05-01), Luke et al.
patent: 6389560 (2002-05-01), Chew
patent: 6393588 (2002-05-01), Hsu et al.
patent: 6480801 (2002-11-01), Chew
patent: 6505263 (2003-01-01), Larson et al.
patent: 6567875 (2003-05-01), Williams et al.
patent: 6615288 (2003-09-01), Herzi
patent: 6658515 (2003-12-01), Larson et al.
patent: 6701401 (2004-03-01), Lu et al.
patent: 2002/0095501 (2002-07-01), Chiloyan et al.
patent: 2002/0095540 (2002-07-01), Zolnowsky
patent: 2002/0156952 (2002-10-01), Shono
patent: 2002/0166072 (2002-11-01), Cromer et al.
patent: 2003/0005197 (2003-01-01), Abramson et al.
patent: 2003/0041205 (2003-02-01), Wu et al.
patent: 2003/0043771 (2003-03-01), Mizutani et al.
patent: 2004/0162929 (2004-08-01), Zolnowsky
patent: 2005/0076171 (2005-04-01), Hanson et al.
patent: 0953486 (1999-11-01), None
patent: 1031931 (2000-08-01), None
IBM Corporation, “Method to Identify Multiple identical USB Devices”, Research Disclosure; (Feb. 1999), p. 258.
IBM Corporation, “Power Up Security for External Device Bay”, Research Disclosure; (Mar. 1999), p. 392.
IBM Corporation, “Remote Detection of Configuration Changes of Hot-Plugable Devices”, Research Disclosure; (Mar. 1999), p. 396.
IBM Corporation, “A Means to Reliably Determine the Steady State of a USB Plug-and-Play System”, Research Disclosure; (Nov. 1999), p. 1544.
“Universal Serial Bus Specification”, Revision 2.0, Chapter 7—Electrical, (Apr. 27, 2000), pp. 119-193.
Burke Thomas Charles
Cromer Daryl Carvis
Dayan Richard Alan
Kern Eric
Springfield Randall Scott
Dillon & Yudell LLP
Huynh Kim T.
Lenovo ( Singapore) Pte. Ltd.
Munoz-Bustamante Carlos
Perveen Rehana
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