IBM totalstorage 200, Hardware Installation Manual

Page: 47 / 152

Figure 17 identifies the switches and jumpers on the system board.
System board jumper blocks
Any jumper blocks on the system board that are not shown in the illustration are
reserved. For normal operation of the system, no jumpers should be installed on
any of the jumper blocks. See Figure 17 for information about the boot block
jumper.
System board switch block
The switch block contains microswitches 1 - 8. Switch 8 is at the top of the switch
block and switch 1 is at the bottom. The Off position for each switch is the side
nearer the diagnostics panel.
Table 4 describes the function for each switch.
Table 4. Switches 1 - 8
Switch
number
Switch
description
8 Bypass power-on password. The default setting is Off.
When toggled to the On position and back to Off, clears the power-on
password, if one is set.
7 Reserved. The default setting is Off.
6 Clock frequency selection. The default setting is Off.
When On, sets the host bus speed to 100 MHz. When Off, the host bus
speed is 133 MHz.
Boot block
jumper (J37)
System board
switch block (SW1) Diagnostics
panel
Figure 17. System board switches and jumpers
Chapter 3. Adding and replacing components
33