DEC Personal DECstation 5000, Руководство пользователя

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Troubleshooting
13.6 Understanding the Powerup Self-Test Sequence and the LED Display
13.6 Understanding the Powerup Self-Test Sequence and the
LED Display
A single LED, mounted on the front of the power supply, flashes several
times during system power-up. These flashes indicate how far the unit has
progressed through the power-up sequence.
By interpreting these flashes you can determine which pieces of the unit are
operational and then deduce which modules are not functional. It is important
to watch the LED closely during the entire power-up sequence.
Note
The front-mounted system LED is a new feature which has been
introduced with the Personal DECstation that is designed as a
diagnostic substitute for the traditional eight-segment LED display
located on the rear of DECstation models 100, 200, and 240. It is not a
DCOK LED.
Troubleshooting 13–9