Ring-back powered telephone with nonvolatile memory structure
US5161184A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 1989 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Aug 9, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04M1/27485
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A programmable telephone powered by a telephone line, and responsive to ringing signals for providing an automatic answer. A microprocessor in the telephone is powered by periodic signals during ringing intervals for executing instructions to count the number of ring cycles, and is placed in a sleep mode if such number does not exceed a predefined threshold. When the threshold number of rings occurs, the microprocessor places the telephone in a simulated off-hook condition for allowing programming of the memory thereof. The memory of the microprocessor is an EEPROM having a file allocation table with addresses pointing to an input dialing pattern table, an area code/exchange code table and to an output dialing pattern table. Multiple levels of user and software security codes are employed to provide a high degree of security to the programming of the telephone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.