Digital Equipment Digital AlphaStation 200 Series Technical Information page 54

Configuring Your AlphaStation System
Table 2-9. AlphaStation 200 Series Motherboard Jumper Locations
(continued)
Jumper Setting
J17 (1 to 2)
(3 to 4)
(5 to 6)
J21 (1 to 2)
Hang Off (D)
J22 (1 to 2) (D)
Removed
J24 (1 to 2) (D)
Removed
J30
(D)= Default setting.
2-16
Function Description
Keyboard controller All are unused.
inputs.
Disables sensing for J21 controls the automatic SCSI bus
presence of external terminator. If an external SCSI cable
cable. is attached to the SCSI connector, the
automatic SCSI terminator turns off.
The SCSI bus must be terminated at
the end of the external bus. When
sensing is disabled (J21 1 to 2
installed), an external SCSI terminator
is required, even if no external SCSI
devices are present.
Enables sensing for If a cable is present, the SCSI bus
the presence of an must be terminated at the end of the
external SCSI cable. external bus.
87332 Super I/O chip. J22 is installed when the 87332 Super
I/O chip is used. This chip supports
87312 Super I/O chip. enhanced parallel port operations.
87332 Super I/O chip. J24 is installed when the 87332 Super
I/O chip is used. This chip supports
87332 Super I/O chip. enhanced parallel port operations.
To be used for future
upgrades.