Abstract: A SCSI bus arbitration controller includes a hub to which each of the SCSI devices having access to the bus is connected. The hub includes a controller that monitors the data lines on the bus, as well as the BUSY and SELECT lines. The hub also includes a plurality of switches located between each of the devices and the data bus. For each set of device connections to a bus, the highest priority ID data line has a switch in it, as does the data line that corresponds to the ID associated with that particular device. During an initial arbitration cycle, the controller monitors the bus data lines, and determines which of the devices participate in the initial arbitration cycle. It then latches the identities of the participating devices in a register. Of the SCSI IDs of the system, the controller reserves the highest priority ID for itself.