User`s manual

General Information
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1
Auto Boot
Note The PowerPlus architecture boards do not execute a
configured boot routine.
Auto Boot is the default boot routine. It provides an independent
mechanism for booting an operating system. No console is
required. Autoboot selects the boot device from either a scan list of
device types, a floppy diskette, a CD-ROM, tape, or a hard disk.
You may change the scan order, or configure Auto Boot to boot
from a specific Controller Logical Unit Number (CLUN) and
Device Logical Unit Number (DLUN) by changing the ENV
command parameters for enabling Auto Boot (refer to Chapter 3 for
information).
At power-up, Auto Boot is enabled. The following message is
displayed on the system console:
Autoboot in progress... To abort hit <BREAK>
Following this message there is a delay to allow you to abort the
Auto Boot process and gain control. Press either the BREAK key or
the software abort or reset switch to abort Autoboot.
If you do not abort Auto Boot, the actual I/O is begun. The program
pointed to within the boot-record of the media specified is loaded
into RAM, and control is passed to it.
Upon power-up or system reset, PPCBug examines the validity of
the configuration parameters in NVRAM. If there is a configuration
error (e.g., corrupted data or checksum error), the PPCBug will
initialize the configuration parameters with the default values, and
run AutoBoot. Following the auto-initialization of the
configuration parameters, the PPCBug will reset the system to
allow a start-up with the now default configuration parameters.