Patent ID: 7133948

Claim:
A controller device for controlling a plurality of target devices connected to a data bus for transferring data in a predetermined communication format, said controller device comprising: a first command generator to generate a first reserve command to permit transmission of commands from the controller device sending the first reserve command to a first target device that accepts the first reserve command from the controller device, and to inhibit communication between the first target device and all other of the target devices and all other controller devices; a second command generator to generate a second reserve command to permit transmission of commands from the controller device to the first target device, and to permit transmission of at least one designated command to said first target device from other controller devices, and to inhibit communication of other than the at least one designated command to said first target device from the other controller devices; and a transmitter to selectively transmit to said target devices and other controller devices said first reserve command generated by said first command generator and to selectively transmit to said target devices said second reserve command generated by said second command generator, wherein said predetermined communication format complies with IEEE 1394 criteria.