IBM RS6000 Service Guide - Page 127

For planars, cards, and non-SCSI devices the location code is defined as: AB-CD-EF-GH Device/FRU/Port ID | | Connector ID | devfunc Number, Adapter Number or Physical Location Bus Type or PCI Parent Bus The AB value identifies a bus type or PCI parent bus as assigned by the firmware. The CD value identifies adapter number, adapter's devfunc number, or physical location. The devfunc number is defined as the PCI device number times 8, plus the function number. The EF value identifies a connector. The GH value identifies a port, address, device, or FRU. Adapters and cards are identified with just AB-CD. The possible values for AB are: 00 Processor bus 01 ISA bus 02 EISA bus 03 MCA bus 04 PCI bus used in the case where the PCI bus cannot be identified 05 PCMCIA buses xy For PCI adapters where x is equal to or greater than 1. The x and y are characters in the range of 0-9, A-H, J-N, P-Z (O, I, and lower case are omitted) and are equal to the parent bus's ibm, aix-loc Open Firmware Property. The possible values for CD depend on the adapter/card. For pluggable PCI adapters/cards, CD is the device's devfunc number (PCI device number times 8, plus the function number). The C and D are characters in the range of 0-9, and A-F (hex numbers). This allows the location code to uniquely identify multiple adapters on individual PCI cards. For pluggable ISA adapters, CD is equal to the order the ISA cards defined/configured either by SMIT or the ISA Adapter Configuration Service Aid. For integrated ISA adapters, CD is equal to a unique code identifying the ISA adapter. In most cases this is equal to the adapter's physical location code. In cases where a physical location code is not available, CD will be FF. Chapter 3. Error Code to FRU Index 3-55