Intel SE7520JR2 Manual Do Utilizador

Revision 1.0 

 
 

1 

Front panel CMOS clear initiated 

1-5-1-1 

FRB failure (processor failure) 

1-5-2-1 

No processors installed or processor socket 1 is empty. 

1-5-2-3 

Processor configuration error (e.g., mismatched VIDs, Processor slot 1 is empty) 

1-5-2-4 

Front-side bus select configuration error (e.g., mismatched BSELs) 

1-5-4-2 

Power fault: DC power unexpectedly lost  (e.g. power good from the power supply was deasserted) 

1-5-4-3 

Chipset control failure 

1-5-4-4 

Power control failure (e.g., power good from the power supply did not respond to power request) 

 

The BIOS sends a 1-byte hex code to port 80 before each task. The port 80 codes provide a 
troubleshooting method in the event of a system hang during POST. Table 75 provides a list of 
the Port 80 codes and the corresponding task description. 

All port 80 codes are displayed using the Diagnostic LEDs found on the back edge of the 
baseboard. The diagnostic LED feature consists of a hardware decoder and four dual color 
LEDs. During POST, the LEDs will display all normal POST codes representing the progress of 
the BIOS POST. Each code will be represented by a combination of colors from the four LEDs.  

The LEDs are capable of displaying three colors: Green, Red, and Amber. The POST codes are 
divided into two nibbles, an upper nibble 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 nibbles then both Red and Green LEDs are lit, resulting 
in an Amber color. If both bits are clear, then the LED is off. 

In the below example, BIOS sends a value of ACh to the Diagnostic LED decoder. The LEDs 
are decoded as follows: 

• 

Red bits = 1010b = Ah 

• 

Green bits = 1100b = Ch 

Since the red bits correspond to the upper nibble and the green bits correspond to the lower 
nibble, the two are concatenated to be ACh. 

Ach 

1 1 0 1 1 0 0 0