Communications Failures - Printronix T4204 Maintenance Manual

Communications Failures

Many host-printer communications problems are complex. With the exception
of a defective interface cable, most communications problems are not a result
of a hardware failure. Communications problems usually result from
incompatible configuration of the host computer system, network (LAN, print
server, controller, multiplexer, etc.), or the printer. Sometimes the print
application program itself is at fault.
If the printer appears to have communication problems, run self-test
configuration test labels and a hex dump to help identify printer configuration
errors that can cause problems. Configuration items to check include the
following:
•
Check that the data string sent to the printer contains the correct
information.
•
Verify that the correct host interface port is being used and that the
communication parameters (i.e., baud rate, parity, etc.) match those of
the host computer.
•
Verify that the correct interface cable is installed between the host
computer and the printer.
•
If the printer is using the parallel interface, verify that the termination
resistors are correct.
If you have limited communications experience, and the cause of the problem
is not readily apparent, do the following:
1. Print out the printer configuration.
2. Obtain a copy of the Device Host Configuration if possible.
3. Call your support group for assistance in problem analysis.
If you cannot obtain support, or you have experience solving host-printer
communications problems, the following additional information is provided.
You can quickly check the ASCII portion of the printer logic by sending a plain
text file from a computer to the printer via the parallel or serial port. For a
description of each of the ASCII interfaces, refer to the User's Manual.
How To Clear LCD Messages
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