Filter
Top Products
34
Configuring the Software Configuration Register
78-4339-09
Implementing Additional Configuration and Maintenance Tasks
Bit 8 controls the console Break key. Setting bit 8 (the factory default) causes the system to ignore the
console Break key. Clearing bit 8 causes the system to interpret the Break key as a command, which
forces the system into the bootstrap (or ROM) monitor, thereby halting normal operation. Regardless of
the setting of the break enable bit, a break causes a return to the ROM monitor during the first few
seconds (approximately 5 seconds) of booting.
Bit 9 is unused.
Bit 10 controls the host portion of the IP broadcast address. Setting bit 10 causes the processor to use all
zeros; clearing bit 10 (the factory default) causes the processor to use all ones. Bit 10 interacts with
bit 14, which controls the network and subnet portions of the broadcast address.
Table 12 shows the combined effect of bits 10 and 14.
Bits 11 and 12 in the configuration register determine the data transmission rate of the console terminal.
Table 13 shows the bit settings for the four available rates. (The factory-set default data transmission rate
is 9600.)
cisco4-GRP 0100
cisco5-GRP 0101
cisco6-GRP 0110
cisco7-GRP 0111
cisco10-GRP 1000
cisco11-GRP 1001
cisco12-GRP 1010
cisco13-GRP 1011
cisco14-GRP 1100
cisco15-GRP 1101
cisco16-GRP 1110
cisco17-GRP 1111
Table 11 Default Boot Filenames (continued)
Action/File Name Bit 3 Bit 2 Bit 1 Bit 0
Table 12 Configuration Register Settings for Broadcast Address Destination
Bit 14 Bit 10 Address (<net> <host>)
Off Off <ones> <ones>
Off On <zeros> <zeros>
On On <net> <zeros>
On Off <net> <ones>
Table 13 System Console Terminal Transmission Rate Settings
Baud Bit 12 Bit 11
9600 0 0
4800 0 1