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8175 N/B MAINTENANCE
8175 N/B MAINTENANCE
7. Maintenance Diagnostic
7.1 Introduction
Every time the computer is turned on ,the system BIOS runs a series of internal checks on the
hardware. This power-on self test (post) allows the computer to detect problems as early as the
power-on stage. Error messages of post can alert you to the problems of your computer.
If an error is detected during these tests, you will see an error message displayed on the screen. If
the error occurs before the display, then the screen cannot display the error message. Error codes
or system beeps are used to identify a post error that occurs when the screen is not available.
The value for the diagnostic post (378H) is written at the beginning of the test. Therefore , if the
test fail, the user can determine where the problem occurs by reading the last value written to
post 378H by the PIO debug board plug at PIO port.
