Dell Latitude XPi CD Reference Guide - Page 91

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 harddisk drives are common, because most hard-disk drives have a small amount of space that is not usable. The harddisk drive keeps a record of this space so that your computer 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 program, files cannot be properly recalled. Subtests The seven subtests in the SCSI Devices Test Group confirm 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 automatically 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. Network 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 network environment, the network connection should be inspected. If the connection is good, run the Network Interface Test Group to determine if the network Running the Dell Diagnostics 4-21