Asus LS99 - Manual (Page 11)

Chapter 2 Hardware Installation 11
2. HW Installation
Follow these steps to connect external SCSI devices:
1. Connect one end of the external SCSI cable to the external Ultra160 connector.
2. Connect the other end of the cable to a SCSI connector on the back of an external
device. Pin-1 must match on all connections. If you are installing only one external
device, terminate the device and skip to step 4.
3. Connect the other external SCSI devices by linking each device to the previous
one. Terminate only the device at the end of the chain.
4. Connect power cables to all external SCSI devices and to the computer.
2.6.5 More Information About Termination
The last SCSI device on the end of each SCSI bus cable must be terminated, and
termination must be disabled for all other devices in the middle of the cables. Ultra160
and Ultra2 SCSI devices are automatically unterminated, but Ultra SCSI and Fast/
Wide SCSI devices do have termination that you must check. For more information,
refer to the Appendix.
If you are using external Ultra2 or Ultra160 devices, be sure to use an LVD terminator
to terminate the last device in the chain. If you use a single-ended, active terminator
(sometimes called an Ultra terminator) the SCSI devices will not operate at their
maximum speed.
2.6.6 Connecting the LED Connector
Most computers have an LED disk activity light on the front panel of the system
case. If you choose to disconnect the cable from the LED connector on the
motherboard and connect it to the LED connector on the LAN/SCSI card as shown
in the diagram below, the LED on the front panel of the computer will light whenever
there is activity on the SCSI bus.
NOTE: If you connect the LED cable to the LAN/SCSI card,the LED
disk activity light will no longer indicate disk activity on the non-
SCSI disk drives.
®
SCSI Activity LED Connector
LED
GND
GND
LED2
LED1
(Channel B)
(Channel A)