Protocol and apparatus for a control link between a control unit and several devices
US5128666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 20, 1990 |
| Grant date | Jul 7, 1992 |
| Priority date | — |
| Expiry date | Feb 20, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F13/423
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An interface and protocol for linking devices (18) with a control unit (10). The interface includes a dedicated request line (30) per device, a dot-ORed acknowledge line (32), at least one clock line (38) transmitting sets of N clock pulses from the control unit to a device during each data exchange, two data line (34, 36) for serial duplex data transmission and a pair of shift registers one being positioned in the control unit and another being positioned in each of the devices. The protocol is such that for either a read or a write operation the control unit issues two request signals in spaced relationship on the request line and the selected device responds with two acknowledge signals is spaced relationship on the acknowledge line with each one of the acknowledge signals falling after the fall of its associated request signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.