Power-On Self Test; Diagnostic Self-Test - Wyse WY-60 Maintenance Manual

Power-on Self-Test
The power-on self-test checks th~ terminal's random access memory
(RAM), read-only memory (ROM), electrically eraseable read-only
memory (EEROM), and external communication ports.
Each time you turn the terminal on, the power-on self-test
occurs. If the test detects an error, an error message appears
on the display. The "Fails Power-on or Diagnostic Self-Tests"
section in Figure 3-1 identifies these errors. If any of these
messages appear, replace or troubleshoot the terminal PCB.
Diagnostic Self-Test
The terminal diagnostic self-test starts in setup mode. This
procedure includes communications circuitry tests, read/write
tests, and row buffer tests. Two special test connectors allow
the diagnostic test to function (see Appendix C for connector
definitions or Chapter 5 for ordering information). After you
start it, the diagnostic test continues to run until you stop it.
If the test detects an error, an error message appears in the
lower right-hand corner of the screen (see "Fails Power-on or
Di3.gnostic Self-Tests" in Figure 3-1).
Follow these steps to start the diagnostic self-test:
1. Turn the term inal off.
2. Detach any communications cables on the back of the terminal.
3.
Attach the test connectors to the MODEM and AUX ports on the
rear of the terminal.
Note--See Appendix C for a description of these test
connectors and instructions to make them. See Chapter 5 to
ord er them.
4. Turn the terminal on.
5. Hold the SHIFT key, then press the SETUP key.
6. Press the F2 key.
setup menu.
Look for to the TEST:OFF field in the
7.
Use the cursor keys to highlight the TEST:OFF field.
8. Press the SPACEBAR. This toggles the TEST field ON.
9. Press the F10 key, then CUSOR RIGHT, then F10 again. You
will see a flashing test pattern.
10. If the test stops, the terminal beeps,·and a letter or
number appears on the screen go to the "Fails Power-on or
Diagnostic Self-Tests" section of Figure 3-1.
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