Data transmission system with a digital alarm facility
US4933672A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 22, 1988 |
| Grant date | Jun 12, 1990 |
| Priority date | — |
| Expiry date | Aug 22, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L1/0083
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The data transmission system includes a data transmitter for transmitting either data bits or a sequence of N alarm bits in a first binary state. The transmitter includes a decode circuit (16) providing a detection signal each time that, in a data bit stream, a sequence of n bits in the first binary state has been loaded in a shift register (14), a XOR circuit (18) modifying the binary state of the bit following the sequence of n bits in response to the detection signal provided by the decode circuit (16), thereby providing a modified data bit stream on the transmit line (20), the number n being chosen so that no modified data bit stream can be formed of N bits in the first binary state which could be confused with the sequence of N alarm bits. On the reception side, the data receiver performs the reciprocal operation of the data transmitter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.