A-1
Cisco 7200 VXR Installation and Configuration Guide
OL-5013-09
APPENDIX
A
Configuration Register Information
The following information is found in this appendix:
  • Configuration Bit Meanings, page A-1
  • Displaying the Configuration Register While Running Cisco IOS, page A-5
  • Displaying the Configuration Register While Running ROM Monitor, page A-5
  • Setting the Configuration Register While Running Cisco IOS, page A-6
  • Setting the Configuration Register While Running ROM Monitor, page A-6
Configuration Bit Meanings
Use the processor configuration register information contained in this appendix to do the following:
  • Set and display the configuration register value
  • Force the system into the bootstrap program
  • Select a boot source and default boot filename
  • Enable or disable the Break function
  • Control broadcast addresses
  • Set the console terminal baud rate
  • Load operating software from ROM
  • Enable booting from a Trivial File Transfer Protocol (TFTP) server
Table A-1 lists the meaning of each of the configuration memory bits. Following the table is a more 
in-depth description of each setting.
Ta b l e  A-1 Configuration Register Bit Settings 
Bit No. Hex Meaning
00–03 0x0000–0x000F Boot field
06 0x0040 Causes the system software to ignore nonvolatile random-access 
memory (NVRAM) contents
07 0x0080 Original Equipment Manufacturer (OEM) bit enabled
08 0x0100 Break disabled
10 0x0400 IP broadcast with all zeros