IBM HANDBOOK 260 - Manual (Page 165)

Adapters, Overview and Configuration 147
The predefined database contains configuration data for all possible devices
configurable for the system.
The customized database contains configuration data for all currently defined
devices in the system.
The device information stored in the Device Configuration Database allows
the automatic configuration PCI devices on PCI-based RS/6000 systems
whenever the Configuration Manager (
cfgmgr ) program is run at system boot
and run time.
The Device Configuration Database that is currently used by the system is
located in the directory that is specified by the ODMDIR environment
variable. This is normally the /etc/objrepos directory.
In AIX Version 3.2, all device software was installed when the operating
system was installed. In AIX Version 4, only those software packages for
devices that were detected at the installation time are automatically installed.
Refer to Managing AIX V.4 on PCI-Based RS/6000 Workstations (40P/43P),
SG24-2581, or to the AIX Version 4 product documentation for more
information on device management and enhancements to the Device
Configuration Database.
5.3.1.2 Device Location Codes
Location codes are defined slightly differently depending on the type of
device they are used for, non-SCSI or SCSI.
For planars, cards and non-SCSI devices, the location code is defined as:
AB-CD-EF-GH
For SCSI devices, the location code is defined as:
AB-CD-EF-G,H
While AB-CD-EF have the same meaning for both non-SCSI and SCSI devices,
the last two letters identify different codes.
AB identifies a bus type, and it can assume the following values:
00 for resources attached to the processor bus, such as system
planar, processor, memory, L2 cache, and primary PCI bus.
01 for resources attached to ISA buses, such as diskette drive,
mouse adapter, mouse, and keyboard.