2 System Board

Devices on the ISA Bus

System Board Switches

The first two of the system board switches set the frequency of the Processor-Local bus, and the next three the ratio of processor-frequency to Processor-Local-bus-frequency, as summarized on page 37.

The next five switches set the configuration for the PC Workstation, as summarized in the table below.

Switch

Switch Function

Default

 

 

 

 

1

Open

Reserved - Do not use (always set to Open).

Open

 

 

 

 

2 - 5

-

Bus Frequencies (see the table on page 37).

-

 

 

 

 

 

 

Retain or clear the CMOS configuration stored in serial EEPROM:

 

6

Open

Do not clear CMOS.

 

 

 

Clear CMOS and reload default values in Setup.

Open

 

Closed

 

 

 

 

 

 

 

Enable or disable User and System Administrator Passwords stored in

 

 

 

EEPROM:

 

7

Open

Enable passwords.

 

 

 

Disable /Clear User and Administrator passwords.

Open

 

Closed

 

 

 

 

 

 

 

Keyboard power-on:

 

8

Open

Disable keyboard power on.

 

 

Closed

Enable keyboard power on.

Closed

 

 

 

 

 

 

 

 

Boot block:

 

9

Open

Idle. Normal operation

 

 

 

 

Open

 

Closed

Recovery boot active. Enable crisis recovery.

 

 

 

 

 

 

10

Open

Reserved = do not use

Open

 

 

 

 

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