Before running any tests, the computer checks DIP switch 1-Zon the front panel to ensure that a coprocessor is installed. If the coprocessor is missing, or if you have not set DIP switch 1-2 correctly, an error occurs and the test ends.

The program then runs a series of checks to test the precision with which the coprocessor performs calculations and to detect whether it correctly handles exceptions. The program reports any errors that occur.

Parallel Port (Printer Interface) Check

Use this option to test the operation of the secondary parallel printer port. For example, you would select this option to test the built-in port if you have assigned it as the secondary port, or if you have installed an option card that provides a parallel port.

To perform the test, you must insert a special loop-back connector into the parallel port so that the computer can check the individual pins of the port. Contact your Customer Care Center if you need a loop-back connector (or see Appendix B for signal/pin assignments to make your own loop-back connector). Note that a different connector is required co test the serial port.

When you select option 9 from the DEVICE LIST, you see these prompts:

Attach loop-back connector to parallel port. Enter Y to start this check when connector is attached, or Enter N to return to the

menu.

Insert the loop-back connector. Then press Y and Enter to start the check.

Performing System Diagnostics

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