# US 6,294,995 B1 · Anti-theft alarm for portable computer > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,294,995 B1 - Document ID: US6294995B1 - Status: Granted - Kind: B1 - Application number: 09/522,812 - Filed: 2000-03-10 - Granted: 2001-09-25 - Earliest claimed: 1999-03-15 - Inventors: Jennifer Patterson - Web page: https://patentgrep.com/patent/US6294995B1 ## CPC - G06F 1/1616: {with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position} - G06F 1/1677: {for detecting open or closed state or particular intermediate positions assumed by movable parts of the enclosure, e.g. detection of display lid position with respect to main body in a laptop, detection of opening of the cover of battery compartment} - G08B 13/1418: {Removal detected by failure in electrical connection between the appliance and a control centre, home control panel or a power supply} - G08B 13/149: {with electric, magnetic, capacitive switch actuation} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS ## Abstract A laptop computer is supplied with special-purpose software that detects when the cover is being closed by an unauthorized person. When the cover is closed, an alarm sounds using the speaker integral the laptop. The closed-cover condition is detected. The software operates on either interrupt-driven devices or polled devices which have some means for detecting that the cover is closed. The software includes a password feature and a hot-key feature for overriding the alarm so that an authorized person may close the cover without disturbing other persons or to stop the alarm if the authorized person forgets to disable the alarm. ## Claims ### Claim 1 A method for causing a speaker to sound an audible alarm in a portable computer having a cover, a main computer body, a hinge between said cover and said body, and an interrupt vector, said method comprising: a) detecting foldable closing of said cover relative to said body; b) causing an interrupt to occur within said portable computer; c) said interrupt causing branching control to a fixed address in said interrupt vector following said detecting; and d) generating said audible alarm from said speaker following said interrupt; and further comprising; detecting whether said speaker is enabled; and detecting whether said alarm is activated by an authorized user. ### Claim 2 (depends on 1) The method according to claim 1, wherein a computer designer assigns said fixed address in said interrupt vector for interrupt handling said interrupt upon detection of said foldable closing of said cover to said body. ### Claim 3 (depends on 2) The method according to claim 2, said fixed address in said interrupt vector comprising an original address for branching control of said portable computer upon occurrence of said interrupt upon detection of said foldable closing of said cover to said body. ### Claim 4 (depends on 3) The method according to claim 3, further comprising a first instruction segment at said original address contained in said fixed address in said interrupt vector, control branching to said instruction segment of said portable computer upon detecting said foldable closing of said cover to said body. ### Claim 5 (depends on 4) The method according to claim 4, further comprising a second instruction segment. ### Claim 6 (depends on 5) The method according to claim 5 wherein said second instruction segment is located at a second address. ### Claim 7 (depends on 6) The method according to claim 6, wherein said second instruction segment causes said speaker to generate said audible alarm. ### Claim 8 (depends on 7) The method according to claim 7, further comprising trapping said interrupt caused by said foldable closing of said cover of said portable computer. ### Claim 9 (depends on 8) The method according to claim 8, wherein said trapping occurs at boot time. ### Claim 10 (depends on 9) The method according to claim 9, wherein said interrupt is trapped by resetting said original address in said interrupt vector to an indirect address of said second address of said second instruction segment. ### Claim 11 (depends on 10) The method according to claim 10, wherein said detecting of said foldable closing of said cover occurs subsequent to boot time. ### Claim 12 (depends on 11) The method according to claim 11, wherein a volume for said alarm is set by said authorized user. ### Claim 13 (depends on 12) The method according to claim 12, wherein said authorized user may deactivate said alarm. ### Claim 14 (depends on 13) The method according to claim 13, wherein said authorized user may select one of a plurality of passwords for deactivating said alarm. ### Claim 15 (depends on 13) The method according to claim 13, wherein said authorized user may select one of a plurality of hot-keys for deactivating said alarm. ### Claim 16 (depends on 12) The method according to claim 12, wherein said authorized user may activate said alarm. ### Claim 17 (depends on 16) The method according to claim 16, wherein said authorized user may select one of a plurality of passwords for activating said alarm. ### Claim 18 (depends on 16) The method according to claim 16, wherein said authorized user may select one of a plurality of hot-keys for activating said alarm. ### Claim 19 A method for causing a speaker to sound an audible alarm in a portable computer having a cover, a main computer body, a hinge between said cover and said main computer body, a status location indicating foldable closing of said cover against said body, and an instruction segment, said method comprising: a) polling said status location to detect said foldable closing of said cover against said main computer body; b) causing execution of said instruction segment following detection of said status location indicating said foldable closing of said cover against said main computer body; c) said instruction segment generating said audible alarm; and further comprising: detecting whether said speaker is enabled; and detecting whether said alarm is activated by an authorized user. ### Claim 20 (depends on 19) The method according to claim 19, wherein a volume for said alarm is set by said authorized user. ### Claim 21 (depends on 20) The method according to claim 20, wherein said authorized user may deactivate said alarm. ### Claim 22 (depends on 21) The method according to claim 21, wherein said authorized user may select one of a plurality of passwords for deactivating said alarm. ### Claim 23 (depends on 21) The method according to claim 21, wherein said authorized user may select one of a plurality of hot-keys for deactivating said alarm. ### Claim 24 (depends on 20) The method according to claim 20, wherein said authorized user may activate said alarm. ### Claim 25 (depends on 24) The method according to claim 24, wherein said authorized user may select one of a plurality of passwords for activating said alarm. ### Claim 26 (depends on 24) The method according to claim 24, wherein said authorized user may select one of a plurality of hot-keys for activating said alarm.