System Board Switches And Jumpers - IBM TotalStorage 200 Service Manual

Figure 11 identifies the switches and jumpers on the system board.
System board jumper blocks
Boot block
jumper (J37)
Figure 11. System board switches and jumpers
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 11 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 18 describes the function for each switch.
Table 18. Switches 1 - 8
Switch Switch
number 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.
System board Diagnostics
switch block (SW1) panel
Chapter 4. Adding and replacing components
49