Digital Equipment Prioris XL 6000 Series, Service Maintenance Manual, Page: 77 / 174

Installing Expansion Boards
7-5
PRIO
RIS
XL
6000
Server Scan Sequence
If the boot device is neither the CD-ROM drive or the diskette drive, then the
operating system will be found on drive C. The location of drive C can be
determined as follows:
1. The search for a bootable device is started from a low ROM address to
a high ROM address (starting at C8000h). The boot device with the
lower address gets higher priority to be assigned as drive C then those
with higher addresses.
2. PCI slots are scanned in ascending order starting with slot 1.
For each bus, the scanning sequence is also in ascending order starting
from device 0 to device 1Fh.
For each device found, the server scans to see if there are any
additional PCI busses on that controller. As PCI busses are detected,
they are assigned the next available PCI bus number in sequence. A
controller such as the Adaptec 2940W has no additional PCI busses
onboard. They would represent a single device on PCI bus 0 if installed
in PCI slots 1 - 3.
The slot priorities are summarized as:
Priority Slot #
1 Slot 1 (Bus 0, Device 0Dh)
2 Slot 2 (Bus 0, Device 0Eh)
3 Slot 3 (Bus 0, Device 0Fh)
4 Embedded SCSI controller