Dell Latitude Xpi CD - Manual (Page 91)

Running the Dell Diagnostics 4-21
Why Run a SCSI Devices Test?
If you check your SCSI hard-disk drive to determine the
amount of available space, your operating system will
probably report problem areas. Problem areas on hard-
disk drives are common, because most hard-disk drives
have a small amount of space that is not usable. The hard-
disk drive keeps a record of this space so that your com-
puter will not attempt to use it. Identification of unusable
disk space, unless it is an unusually large amount (over
five percent of the possible total), should not be regarded
as a cause for testing the hard-disk drive.
These are the most common symptoms that might prompt
you to test a SCSI device:
• A SCSI hard-disk drive fails during the boot routine.
• Seek errors are reported by the operating system or
application programs.
• An error message appears on the screen stating that
the computer cannot read from or write to a SCSI
device.
• Data on a SCSI device is corrupted or lost; these
problems may be intermittent. Once saved by a pro-
gram, files cannot be properly recalled.
Subtests
The seven subtests in the SCSI Devices Test Group con-
firm the following drive functions:
• Internal Diagnostic Test
Causes the device to run its internal self-test.
• Seek Test
Checks the device's ability to search for a specified
track on the device and to position its read/write
heads to all tracks.
• Read Test
Positions the read/write heads at each block of the
device for reading data and verifies that all tracks on
the device can be read correctly.
• Write Test
Positions the read/write heads at each block of the
device and verifies that all tracks on the device can
be written to correctly.
• Audio Output Test
Causes the drive to begin playing the first audio
track on an audio CD. (To determine if the test
passed, listen to the audio output of the drive.)
NOTE: The Audio Output Test does not run automat-
ically as part of the SCSI Devices Test Group; you
must select the subtest individually.
• Eject Removable Media Test
Causes a CD-ROM drive to eject its CD, or a SCSI
tape drive to eject its tape cartridge.
• Display Information Test
Displays a screen of information about the SCSI
controller in the replicator, the resources allocated to
the controller, and a list of target devices attached to
it.
N
etwork Interface Test Group
The subtests in the Network Interface Test Group verify
the basic operation of the network interface controller in
the Dell Latitude Advanced Port Replicator. They test the
controller’s internal functions, including read and write
access to its registers and internal transmit and receive
(loopback) capability.
Why Run a Network Interface Test?
Running a subtest in the Network Interface Test Group
helps diagnose problems that may occur while using a
Dell Latitude XPi computer in a network environment.
Most network failures are caused by one of the
following:
• Poor network connections
• Failure in the network controller
• Interrupt conflict (the controller trying to use the
same IRQ line as another device)
• Software configuration error
If a problem occurs while using the computer in a net-
work environment, the network connection should be
inspected. If the connection is good, run the Network
Interface Test Group to determine if the network