Epson Y16499100301 - Manual (Page 121)

Run all above checks
To run all the tests on the menu in sequence, press 5 and
Enter.
When you choose this option, all checks for the diskette
drive(s) and controller are performed automatically in
sequential order. Although you do not start each test, you
must still supply the appropriate responses to progress from one
test to the next.
Parallel Port (Printer Interface) Check
Use this option to test the operation of the parallel printer
port.
To perform the test, you must insert a special loop-back
connector into the parallel port so that the computer can
check individual pins of the port. Contact your dealer if you
need a loop-back connector. Note that a different connector is
required to 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.
The computer checks the port by writing and reading data
and control information and reports errors for any pins that
are faulty. Note that if you connect a printer cable instead of a
loop-back connector, you get errors.
Serial Port (RS-232C) Check
Use this option to test the functions of the serial
communications (RS-232C) port if you have turned off DIP
switch 4 on the back panel. To perform the test, you must
Performing System Diagnostics
D-17