05128666 is referenced by 10 patents and cites 14 patents.

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.

Title
Protocol and apparatus for a control link between a control unit and several devices
Application Number
171067
Publication Number
5128666
Application Date
February 20, 1990
Publication Date
July 7, 1992
Inventor
Jean Claude Robbe
Cagnes sur Mer
FR
Michel Poret
Villeneuve Loubet
FR
Jean Marie Munier
Cagnes sur Mer
FR
Agent
Joscelyn G Cockburn
Assignee
National Business Machines Corporation
NY, US
IPC
G05B 23/00
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