Patent ID: 6842104

Claim:
A cross-bus switch apparatus operable to connect master buses on a bus connection requesting side to slave buses on a bus connection requested side, the cross-bus switch apparatus comprising: a first-layer cross-bus switch unit; N second-layer cross-bus switch units; N connection buses; a plurality of source buses; and a plurality of destination buses, N being an integer equal to or larger than 1, wherein the N connection buses, which are each operable to connect the first-layer cross-bus switch unit to corresponding one of the N second-layer cross-bus switch units directly, are each connected as a slave bus to the first-layer cross-bus switch unit, and are each connected as a master bus to the corresponding one of the N second-layer cross-bus switch units, each of the plurality of source buses is connected to one or more source apparatuses on a data transfer requesting side, and is connected to the first-layer cross-bus switch unit and one of the N second-layer cross-bus switch units, each of the plurality of destination buses is connected to one or more destination apparatuses on a data transfer requested side, and is connected to the first-layer cross-bus switch unit and one of the N second-layer cross-bus switch units, the first-layer cross-bus switch unit is connected to a set of source buses as a set of master buses, and is connected to a set of one or more destination buses and N connection buses as a set of slave buses, the first-layer cross-bus switch unit including arbitration means for each slave bus connected to the first-layer cross-bus switch unit, each of the N second-layer cross-bus switch units is connected to a set of one or more source buses and a connection bus as a set of master buses, and is connected to a set of one or more destination buses as a set of slave buses, each of the N second-layer cross-bus switch units including arbitration means for each slave bus connected thereto, and when two or more master buses connected to a cross-bus switch unit send requests to the cross-bus switch unit for a connection to a slave bus, an arbitration means corresponding to the requested slave bus selects one out of the two or more master buses and connects the selected master bus to the requested slave bus.