Technical data

2-10 Computer Group Literature Center Web Site
Startup and Operation
2
❏ Your routine passes a checksum test, which ensures that this routine
was really intended to receive control at powerup.
For complete details on using the ROMboot function, refer to the
Debugging Package for Motorola 68K CISC CPUs User’s Manual.
Network Boot
Network Auto Boot is a software routine contained in the 172Bug
Flash/PROM that provides a mechanism for booting an operating system
using a network (local Ethernet interface) as the boot device. The Network
Auto Boot routine automatically scans for controllers and devices in a
specified sequence until a valid bootable device containing boot media is
found or until the list is exhausted. If a valid bootable device is found, a
boot from that device is started. The controller scanning sequence goes
from the lowest controller Logical Unit Number (LUN) detected to the
highest LUN detected. (Refer to Appendix C for default LUNs.)
At power-up, Network Boot is enabled and (provided that the drive and
controller numbers encountered are valid) the following message is
displayed upon the system console:
Network Boot in progress... To abort hit <BREAK>
After this message, there is a delay to let you abort the Auto Boot process
if you wish. Then the actual I/O is begun: the program pointed to within
the volume ID of the media specified is loaded into RAM and control
passed to it. If, however, during this time you want to gain control without
Network Boot, you can press the <BREAK> key or the software
ABORT
or
RESET switches.
Network Auto Boot is controlled by parameters contained in the NIOT
and ENV commands. These parameters allow the selection of specific
boot devices, systems, and files, and allow programming of the Boot delay.
Refer to the ENV command description in Chapter 3 for more details.