IBM B50 - Manual (Page 99)

For async devices, GH defines the port on the fanout box. The values are 00 to
15.
For a diskette drive, H identifies either diskette drive 1 or 2. G is always 0.
For all other devices, GH is equal to 00.
For integrated adapter, EF-GH is the same as the definition for a pluggable adapter.
For example, the location code for a diskette drive is 01-D1-00-00. A second
diskette drive is 01-D1-00-01.
SCSI devices/drives
The location code for SCSI devices and drives is defined as:
AB-CD-EF-G,H
| | | | |
| | | | Logical Unit address of the SCSI Device
| | | Control Unit Address of the SCSI Device
| | Connector ID
|
devfunc Number, Adapter Number or Physical Location
Bus Type or PCI Parent Bus
Where:
AB-CD-EF are the same as non-SCSI devices.
G defines the control unit address of the device. Values of 0 to 15 are valid.
H defines the logical unit address of the device. Values of 0 to 255 are valid.
A bus location code is also generated as 00-XXXXXXXX, where XXXXXXXX is
equivalent to the node's unit address.
Chapter 4. Location Codes 4-5