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Scsi devices test group – Dell Latitude CPi A User Manual

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System Setup program to see if the port has been disabled. The subtests in the Parallel Ports test group
cannot test a port unless it is enabled.

When a port is faulty, it may not be immediately evident that the port, and not the device connected to the
port, is faulty. Instead, the peripheral (such as a printer) might behave erratically or not operate at all. Also, if
the external device is not properly installed through software, it may not function properly. Try operating the
peripheral from different programs or through the operating system. If it still does not work, you can eliminate
the software setup as the cause of the problem.

Another possible cause for errors is a problem with the external device itself. Use the documentation that
came with the peripheral to troubleshoot it and confirm that it is working properly. (Most printers have a self-
test.)

After you eliminate incorrect system configuration information settings, peripheral malfunctions, and software
errors as potential causes of port problems, you can run the subtests in the Parallel Ports test group to check
your hardware. Although the following symptoms can be caused by faulty peripherals or software errors, they
might also suggest a port problem:

If a peripheral works intermittently or produces intermittent errors, the port may be faulty.
If the computer displays an error message that is related to the external device connected to a port, but
corrections to the device do not resolve the error, run the appropriate subtest in the Parallel Ports test
group.
If your software and the diagnostics do not recognize that you have a parallel port, you should check
the Parallel Mode system setup option, and if necessary, run the appropriate subtest in the Parallel
Ports test group.

Subtests

The four subtests in the Parallel Ports test group confirm the following port functions:

Parallel Internal Test

Checks several internal functions of the parallel port

Parallel External Loopback Test

Tests the functionality of the control lines through an external loopback connector, if an external
loopback connector is available

Parallel External Interrupt Test

Tests the parallel port's ability to generate interrupts from all possible sources, if an external loopback
connector is available

Parallel Printer Pattern Test

Tests whether the port(s) can retain data, print text on a printer, and generate interrupts

SCSI Devices Test Group

The subtests in the SCSI Devices test group check the functionality of the small computer system interface