Alarm control algorithm for multi-sourced alarms

• US 6,734,794 B2
• Filed: 02/27/2002
• Issued: 05/11/2004
• Est. Priority Date: 02/27/2002
• Status: Expired due to Fees

• Current Assignee: AG Communication Systems Corp. (Nokia Corporation)
• Original Assignee: AG Communication Systems Corp. (Nokia Corporation)
• Inventors: Sciabica, Frank, Robbins, John R.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US10/084,084
• Publication Number:
  US 20030160691A1
• Time in Patent Office: 804 Days
• Field of Search: 340/506, 340/507, 340/517, 340/525, 340/514, 340/519, 340/520, 340/521, 340/522, 340/3.43, 700/12, 700/17, 700/83, 702/187
• US Class Current: 340/521
• CPC Class Codes: G08B 25/008 Alarm setting and unsetting, i.e. arming or disarming of the security system
• CPC Class Codes: G08B 29/10 Monitoring of the annunciator circuits
• CPC Class Codes: G08B 29/18 Prevention or correction of operating errors G08B29/02, G08B29/12 take precedence

Abstract

A state machine that allows an audible alarm for a given fault condition to be extinguished while allowing subsequent audible alarms for different fault conditions.

Claims

1. An audible alarm controller for controlling an audible alarm, receiving a plurality of alarm signals, each of said alarm signals corresponding to the occurrence of a different fault condition, and receiving a manual alarm off signal, said audible alarm controller comprising:

an idle state in which said audible alarm is not sounded;

a plurality of audible alarm states, said audible alarm states in one-to-one correspondence to said alarm signals;

each of said audible alarm states comprising logic to sound said audible alarm, an alarm history flag, and logic to set said alarm history flag indicating that the corresponding fault condition has occurred;

said idle state comprising logic operated in response to the assertion of one of said alarm signals, to move to the corresponding one of said audible alarm states if the corresponding said alarm history flag is not set; and

each of said audible alarm states further comprising logic to return to said idle state when said manual alarm off signal is asserted.

2. An audible alarm controller according to claim 1, wherein certain of said corresponding alarm history flags are permanently not set.

3. A method for controlling an audible alarm, said method comprising:

waiting in an idle state in which said audible alarm is not sounded;

receiving an alarm signal of a plurality of alarm signals indicating the occurrence of a fault condition corresponding to said alarm signal;

remaining in said idle state if an alarm history flag corresponding to said alarm signal is set;

sounding said audible alarm if said corresponding alarm history flag is not set, and setting said corresponding alarm history flag;

receiving a manual off signal;

extinguishing said audible alarm in response to receiving said manual off signal; and

returning to said waiting in an idle state step.

4. A method according to claim 3, wherein certain of said corresponding alarm history flags are permanently not set.