Mylex AcceleRAID 170, Installation Manual

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Installation
Manual No. 775064 2-11
☛
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 2-3 on page
2-15.
☛
Note
To avoid problems caused by mixing drive types,
please refer to “Limitations on Mixing SCSI Drives”
on page 2-16.
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 170 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 if
SCSI devices are connected to the SCSI channel. See Figure 2-9 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.