MiTAC 7521 PLUS/N - Manual (Page 99)

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7521 7521 Plus / N N/B MAINTENANCE Plus / N N/B MAINTENANCE
7. Maintenance Diagnostics
7.1 7.1 Introduction Introduction
Each time the computer is turned on, the system bios runs a seri Each time the computer is turned on, the system bios runs a seri es of internal es of internal
checks on the hardware. This power checks on the hardware. This power - - on self test (post) allows the computer to on self test (post) allows the computer to
detect problems as early as the power detect problems as early as the power - - on stage. Error messages of post can alert on stage. Error messages of post can alert
you to the problems of your computer. you to the problems of your computer.
If an error is detected during these tests, you will see If an error is detected during these tests, you will see an error message an error message
displayed on the screen. If the error occurs before the display displayed on the screen. If the error occurs before the display is initialized,then the is initialized,then the
screen cannot display the error message. Error codes or system b screen cannot display the error message. Error codes or system b eeps are used to eeps are used to
identify a post error that occurs when the screen is not availab identify a post error that occurs when the screen is not availab le. le.
The value for the diagnostic port The value for the diagnostic port (378H) (378H) is written at the beginning of the test. is written at the beginning of the test.
Therefore, if the test failed, the user can determine where the Therefore, if the test failed, the user can determine where the problem occurred by problem occurred by
reading the last value written to port reading the last value written to port 378H 378H by the by the 378H 378H port debug board plug at port debug board plug at
PIO PORT. PIO PORT.