A data transfer control system for multiple units on a common bus using a serially transmitted transfer permission signal
US4471425A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1981 |
| Grant date | Sep 11, 1984 |
| Priority date | — |
| Expiry date | Feb 22, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/37
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A data-transfer controlling system comprising a bus-control unit connected to a common bus for controlling data transfer through the bus and a plurality of transmitter/receiver units for transferring data through the common bus to each other. The bus is comprised of a transfer-request signal line connected to each of the transmitter/receiver units, one or two permission-signal lines, for permitting transfer of data by a transmitter/receiver unit which has been generating a transfer-request signal, an acknowledge signal line, and a transfer-end signal line. The bus does not include a busy-interlock signal line, which was included in the prior art. The transmitter/receiver unit which has received the permission signal begins to transfer data when both of the permission signal and the transfer-end signal are terminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.