Avago Technologies AcceleRAID 170LP - Manual (Page 34)

Installation Process
2-14 AcceleRAID 170LP Installation Guide
☛
Note
A combined configuration using both internal and
external connectors works best with high quality
cables. It is recommended that you use an
Amphenol® Fast 40 LVD, round cable and a
Hitachi® twisted pair, flat cable in this unique setup.
☛
Note
In order to ensure an error free environment, the
proper cable type designed for a certain SCSI
speed must be used, please refer to Table 2-4 on page
2-18.
☛
Note
To avoid problems caused by mixing drive types,
please refer to “Limitations on Mixing SCSI Drives”
on page 2-19.
SCSI Termination
Each end of a SCSI bus must be terminated to maintain proper voltage levels
for SCSI control and data signals. The device used for this purpose is called
a terminator. Termination devices can be built into a controller, a SCSI
device, or attached to the end of a SCSI bus.
The AcceleRAID 170LP controller is equipped with automatic SCSI bus
termination circuitry. If the controller is at the end of a SCSI bus, it
automatically enables on-board termination. The controller can also detect
whether single-ended (SE) or low-voltage differential (LVD) termination is
required, and can automatically configure the appropriate termination type.
The end of the SCSI bus farthest from the controller must be terminated. See
Figure 2-13 for an example of a SCSI device configuration connected to the
internal SCSI channel.
☛
Note
When connecting SCSI devices, it is better to
terminate the ends of the SCSI bus itself, rather than
to terminate the end devices on the bus. This allows
hot swap devices to be added or removed from the
SCSI bus without affecting termination.