Installation guide

E-2 Cisco 4000 Series Installation Guide
Entering the Cisco 4000-M ROM Monitor Program
Timesaver Break (system interrupt) is always enabled for 60 seconds after rebooting the
system, regardless of whether Break is configured to be off by setting the configuration
register. During the 60-second window, you can use Break to get to the ROM monitor
prompt.
Available ROM Monitor Commands
At the ROM monitor prompt, enter a question mark (?) at the > prompt to display a list of
available commands and options, as follows:
?
$ Toggle cache state
B [filename] [TFTP Server IP address | TFTP Server Name]
Load and execute system image from ROM or from TFTP server
C [address] Continue [optional address]
D /S M L V Deposit value V of size S into location L with modifier M
E /S M L Examine location L with size S with modifier M
G [address] Begin execution
H Help for commands
I Initialize
K Displays Stack trace
L [filename] [TFTP Server IP address | TFTP Server Name]
Load system image from ROM or from TFTP server, but do not
begin execution
O Show software configuration register option settings
P Set break point
S Single step next instruction
T function Test device (? for help)
Deposit and Examine sizes may be B (byte), L (long) or S (short).
Modifiers may be R (register) or S (byte swap).
Register names are: D0-D7, A0-A7, SS, US, SR, and PC.
The following Cisco 4000-M ROM monitor commands are among the most useful:
• Boot—The b command with no argument reboots the system and boots the default
software from ROM as defined by the lower four bits of the configuration register, which
form the boot field. You can include an argument, filename, to specify a file to be booted