Maintenance

Troubleshooting

Virtual Configuration Register Settings

Bit 8 controls the console Break key. Setting bit 8 (the factory default) causes the processor to ignore the console Break key. Clearing bit 8 causes the processor to interpret the Break key as a command to force the system into the bootstrap monitor, thereby halting normal operation. A break can be sent in the first 60 seconds while the system reboots, regardless of the configuration settings.

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. (See table 4-6.)

Table 4-6.

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 baud rate of the console terminal.

Table 4-7 shows the bit settings for the four available baud rates. (The default baud rate is 9600.)

Table 4-7.

System Console Terminal Baud Rate Settings

 

 

 

 

Baud

Bit 12

Bit 11

 

 

 

 

9600

0

0

 

4800

0

1

 

1200

1

0

 

2400

1

1

 

 

 

 

 

Bit 13 determines the server response to a bootload failure. Setting bit 13 causes the server to load operating software from ROM after five unsuccessful attempts to load a boot file from the network. Clearing bit 13 causes the server to continue attempting to load a boot file from the network indefinitely. The default setting for bit 13 is 1.

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