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Cisco 10008 Router PRE4 Installation and Configuration Guide
OL-13840-01
Managing System Boot Parameters
Table 8
Definition of Bits in the Software Configuration Register
Bit No.
Hex Value
Meaning/Function
00 to 03
0x0000 to 0x000F
Defines the source of a default Cisco IOS software image required to run the router:
•
00—At power-on, the system remains at the ROM monitor prompt (
rommon>
),
awaiting a user command to boot the system manually by means of the ROMmon
boot
command.
•
01—At power-on, the system automatically boots the first system image found on
the PRE4.
•
02 to 0F—At power-on, the system automatically boots from a default Cisco IOS
software image stored on a TFTP server in the network. For this setting, the
Fast Ethernet port on the PRE4 must be configured and operational. This setting
also enables boot system commands that override the default filename.
06
0x0040
Causes system software to ignore the contents of NVRAM.
07
0x0080
Enables the original equipment manufacturer (OEM) bit.
08
0x0100
The Break function is disabled after 30 seconds.
09 0x0200
Not
used.
10 0x0400
Broadcast
based on 0.0.0.0 IP address.
11 and 12
0x0800 to 0x1000
Defines the console baud rate (the default setting is 9600 baud).
13
0x2000
Boots an image from Disk0.
14
0x4000
Broadcast using the subnet broadcast address.
15
0x8000
Enables diagnostic messages and ignores the contents of NVRAM.