Abstract: A method for decoding a DTMF tone which includes collecting the width of serial signals by measuring the time interval between zero-crossing points within a predetermined time; counting within the predetermined time the number of signal zero-crossing points; performing interpolation on the data produced by the collecting and counting steps with a Fourier transform; identifying a first frequency that has the strongest magnitude from the resulting data; and calculating the lower frequency of the tone being decoded by subtracting the first frequency from the average frequency of the digitized signal.

Abstract: A security system for protecting a building which includes at least a first presence sensor, an alarm panel that includes a microprocessor and memory, an exit delay in the alarm panel providing an interval for a user to exit the building after arming the security system, a reset of the exit delay providing a still further interval for a user to exit the building after arming the security system, the reset being initiated by the first presence sensor. The invention also includes the method for protecting a building which includes providing at least a first presence sensor, providing an alarm panel that includes a microprocessor and memory, providing a reset in the alarm panel having an interval for a user to exit the building after arming the security system, and initiating the reset in the alarm panel to provide an interval for a user to exit the building after arming the security system. The reset is initiated by the first presence sensor.

Abstract: A security system which includes at least a first sensor, an alarm panel including a control system and programmable apparatus, a connection between the at least one sensor and set alarm panel, a keypad assembly including a camera, and a connection between the keypad assembly and the alarm panel. In various embodiments of the invention the camera includes a CMOS image sensor, the camera produces digital images, the camera tracks the user of the keypad assembly, the camera is remotely controllable from the alarm panel to focus on an object of interest, and/or the camera is remotely controllable from a central monitoring station to focus on an object of interest. In some cases the camera system is configured to take a picture in response to a specific user code entered by the user, take a picture in response to time of day when the input occurs, take a picture in response to invalid code entry and/or take a picture in response to an invalid card being presented.

Abstract: Apparatus for detecting the breaking of a contact-sensitive surface includes an acoustic, shock, and vibration transducer, a detector circuit responsive to the transducer for detecting an acoustic wave resulting from a contact force applied to the surface and generating a signal, a support for the transducer, and the means for disqualifying a contact force to the support as a breakage event that relies on differentiation of the speed with which a shock wave travels through a solid material versus the speed with which an acoustic wave travels through air. The transducer may include a front electret condenser microphone and in some preferred embodiments the microphone does not have a preamplifier associated therewith.

Abstract: Apparatus for remotely changing the sensitivity of a sensor in a security system which includes at least a first sensor having at least first and second outputs corresponding respectively to first and second sensitivity settings, and programmable apparatus cooperating with the first and second outputs of the first sensor. The programmable apparatus is programmable to operatively connect one of the first and second outputs. The apparatus also includes a transmitter coupled to the sensor for transmitting the output of the sensor to an associated security system alarm panel. The invention also includes the method for remotely changing the sensitivity of a sensor in a security system which includes providing at least a first sensor having at least first and second outputs corresponding respectively to first and second sensitivity settings, providing a programmable apparatus for operatively connecting one of the first and second outputs of the first sensor.