Subtests
The subtests in the Parallel Ports Test Group and the port functions they confirm follow:
•Internal Test
Checks several internal functions of the parallel port.
•External Loopback Test
Tests the functionality of the control lines through an external loopback connector, if an external loopback connector is available.
•External Interrupt Test
Tests the parallel port’s ability to generate interrupts from all possible sources, if an external loopback connector or printer is available.
•Printer Pattern Test
Tests a printer and tests the parallel port’s ability to send a pattern to the printer, if connected.
Why Run a Parallel Ports Test?
If the diagnostics does not recognize the computer’s par- allel port, enter the system setup program and check the Parallel Port
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. If the external device is not properly installed through the software, it also may not function properly. Try operating the periph- eral 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 the external device. Use the documentation that came with the peripheral to troubleshoot it and confirm that it is working properly.
Most printers have a
After you eliminate incorrect system configuration infor- mation 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 the 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 the software and the diagnostics do not recognize that you have a parallel port, you should check the Parallel Port
SCSI Devices Test Group
The subtests in the SCSI Devices Test Group check the functionality of up to four small computer system inter- face (SCSI) host adapters and all the SCSI devices attached to them.
NOTES: Before conducting these subtests on
If a
Subtests
The subtests in the SCSI Devices Test Group and the drive functions they confirm follow:
•Internal Diag. Test
Causes the device to run its internal
•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.