Patent ID: 7386634

Claim:
A bus control method for a bus, which is provided with a switch having a plurality of master ports for connecting a plurality of masters and a plurality of slave ports for connecting a plurality of slaves, wherein the switch can establish connection paths between each of the plurality of masters and an arbitrary one of the plurality of slaves for transmitting and receiving a command, an address, and data via the switch, said method comprising: a read command transaction step for issuing a first switch request from a first master to the switch for connecting with a first slave, establishing a first connection path between the first master and the first slave through the switch, issuing a first address and a first read command from the first master to the first slave via the first connection path, and releasing the first connection path before read return data corresponding to the first read command is issued from the first slave; and a read data transaction step for issuing a second switch request from the first slave to the switch for connecting with the first master if the read return data is ready after the first connection path is released in the read command transaction step, establishing a second connection path between the first slave and the first master via the switch independent from the first connection path established in the read command transaction step, and issuing the read return data from the first slave to the first master via the second connection path, wherein, before the read data transaction step is completed, a read command transaction step of a next read transaction can be initiated.