Integrated alarm and touch tone telephone system
US4791658A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 9, 1986 |
| Grant date | Dec 13, 1988 |
| Priority date | — |
| Expiry date | Jul 9, 2006 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M11/045
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A microprocessor controlled integrated alarm and touch tone telephone system which allows the alarm system to be accessed, programmed, and reported upon through a touch tone telephone, either locally or remotely. Under most circumstances, the telephones on the premises can be operated in a normal manner. However, the alarm system selectively monitors the telephone activities for coded touch tone instructions specifically for the alarm system, and responds thereto by issuing synthesized voice reports on the status of the alarm system. A touch tone decoder circuit decodes dialed touch tones, such that the telephone can be utilized similar to a normal keyboard panel to access and control the alarm system. An internal power supply is provided for the telephone for supplying electrical power thereto independently of the outside telephone lines which normally supply power, in the event the outside telephone lines are inoperative. A ring detector circuit is provided for detecting the presence of a ring voltage across the outside telephone lines, and the microprocessor is responsive to a detected ring voltage to disconnect the telephone from the internal power supply and connect it to the …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.