1 /BUS_NUMBER
/BUS_NUMBER=number Specifies the USB bus number of the device. This parameter is required to identify a particular device on a system that has multiple USB buses. If you do not use this qualifier, the bus number defaults to zero. The number can be any number from 0 through 25.
2 /PATH
/PATH=(n1[.n2.n3.n4.n5.n6]) Specifies the path to the device on the bus. The path is used to uniquely identify a device if the device does not have a serial number. The path specification is a series of six or fewer numbers, where: n1 is the number of the root hub (at tier 0). n2 through n6 are port numbers for downstream hubs at tiers 1, 2, 3, 4, and 5. For example, /PATH=1.4.3 indicates that the device is in turn plugged into port 3 of the second tier, which is plugged into port 4 of the first tier, which in turn is plugged into the root hub 1.
3 /UNIT_NUMBER
/UNIT_NUMBER=number Unit numbers can be between 0 and 9999. By default, the configuration code selects the next available unit number. This qualifier allows you to change the unit number to suit your needs.