US 5,345,566 A · Method and apparatus for controlling dual bus system

Abstract

A method and apparatus for controlling a dual bus system, capable of realizing high speed and continuous operation even if one of the buses of the dual bus system fails. The method and apparatus has a dual bus system, a plurality of electronic circuits connected to both buses of the dual bus system, and bus controller for providing a bus use allowance signal to one of the plurality of electronic circuits, the one electronic circuit being selected in accordance with bus occupation request signals issued from the plurality of electronic circuits requesting data transfer. If the bus occupation request signals for both buses of the dual bus system originates from the one selected electronic circuit and the outputs of the arbiters coincide, the bus use allowance signal is provided to the one selected electronic circuit for the allowance of occupying both buses of the dual bus system. A completion of data transfer at the dual bus system is determined when data transfer is completed at both buses. Continuous operation can be ensured immediately upon occurrence of a failure, and high speed operation of a computer system is possible.

Claims7

Dependent claims

The dual bus control method having a dual bus system, a plurality of electronic circuits, each having a dual bus interface, connected to both buses of said dual bus system, and bus controllers, each of said bus controllers being connected to both of said buses and being interconnected by interactive paths, each of said bus controllers providing a bus use allowance signal through an arbiter thereof to one of said plurality of electronic circuits having issued a bus use request signal through a request line thereto, said dual bus control method comprising the steps of:

providing said bus use allowance signal to said one electronic circuit for allowing occupation of both buses of said dual bus system if said bus occupation request signals for both buses of said dual bus system originate from said one selected electronic circuit and said bus use allowance signals, via said arbiter, from said bus controllers coincide with one another;
determined completion of data transfer by said bus controllers at said dual by system if data transfer is completed at both buses;
and
when an intermittent fault occurs on one of said buses of said dual bus system and a retry operation is to be executed, a retry operation executing on the other of said buses.

1 more element

The dual bus control apparatus having a dual bus system, a plurality of electronic circuits, each having a dual bus interface, connected to both buses of said dual bus system, and bus controllers, each of said bus controllers being connected to both of said buses and being interconnected by interactive paths, each of said bus controllers providing a bus use allowance signal through the buses to one of said plurality of electronic circuits having issued a bus use request signal through request line thereto, said dual bus control apparatus comprising:

two bus interface units provided to each of said plurality of electronic circuits and connected to both buses of said dual bus system, said two bus interface units sending said bus occupation request signals to said buses for the data transfer to said buses, starting data transfer to said buses when both of said bus use allowance signals are received, and terminating the bus use when data transfer to both buses is completed;
and
two bus arbitration controllers provided to said bus controller and connected to both buses of said dual bus system, each of said two bus arbitration controllers comprising an arbiter for selecting one of said bus occupation request signals from said plurality of electronic circuits, and a comparator for providing said bus use allowance signal for the buses of said dual bus system if two of said arbiters selected the same electronic circuit;
wherein said two bus interface units of said electronic circuit are provided with a means for, when an intermittent fault occurs on one of said buses of said dual bus system and a retry operation is to be executed, executing a retry operation also on the other of said buses.

1 more element

Dependencies are inferred from the claim text.

Method and apparatus for controlling dual bus system

Life of this patent

Method and apparatus for controlling dual bus system

Life of this patent

Abstract

Claims7