Cisco Systems GRP-B manual Bit Address net host, Baud Bit

Implementing Additional Configuration and Maintenance Tasks

Table 11 Default Boot Filenames (continued)

Action/File Name	Bit 3	Bit 2	Bit 1	Bit 0
cisco4-GRP	0	1	0	0
cisco5-GRP	0	1	0	1
cisco6-GRP	0	1	1	0
cisco7-GRP	0	1	1	1
cisco10-GRP	1	0	0	0
cisco11-GRP	1	0	0	1
cisco12-GRP	1	0	1	0
cisco13-GRP	1	0	1	1
cisco14-GRP	1	1	0	0
cisco15-GRP	1	1	0	1
cisco16-GRP	1	1	1	0
cisco17-GRP	1	1	1	1

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.

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>

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.)

Table 13 System Console Terminal Transmission Rate Settings

			Baud	Bit 12	Bit 11
9600				0	0
4800				0	1
		Configuring the Software Configuration Register
	34				78-4339-09