Acer R700 사용자 설명서

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Diagnostic LEDs
To help diagnose POST failures, a set of four bi-color diagnostic LEDs is 
located on the back edge of the baseboard. Each of the four LEDs can 
have one of four states: Off, Green, Red, or Amber.
The LED diagnostics feature consists of a hardware decoder and four 
dual color LEDs. During POST, the LEDs will display all normal Port80 
codes representing the progress of the BIOS POST. Each postcode will 
be represented by a combination of colors from the 4 LEDs. The LEDs 
are in pairs of green and red. The post codes are broken into two 
nibbles, an upper and a lower nibble. Each bit in the upper nibble is 
represented by a red LED and each bit in the lower nibble is 
represented by a green LED. If both bits are set in the upper and lower 
nibble then both red and green LEDs are lit, resulting in an amber 
color. Likewise, if both bits are clear then the red and green LEDs are 
off.
During the POST process, each light sequence represents a specific 
Port-80 POST code. If a system should hang during POST, the Diagnostic 
LEDs will present the last test executed before the hang. When reading 
the lights, the LEDs should be observed from the back of the system. 
The most significant bit (MSB) is the first LED on the left, and the least 
significant bit (LSB) is the last LED on the right.
Note: When comparing a diagnostic LED color string from the 
baseboard to those listed in the diagnostic LED decoder in the 
following tables, the LEDs on the baseboard should be referenced 
when viewed by looking into the system from the back. Reading 
the LEDs from left to right, the Hi bit is located on the left.
Post Code table: 
Post 
Code
Diagnostic LED Decoder
Description
G=Green,R=Red,A=Amber
MSB
LSB
07h
Off 
G
G
G
Uncompress various BIOS 
Modules.
08h
G
Off
Off
Off
Verify password Checksum.
BS811.f/cppl!!Qbhf!::!!Uvftebz-!Opwfncfs!37-!3113!!21;19!BN