Appendix D: Post Code Diagnostic Led Decoder; Figure 52. Diagnostic Led Placement Diagram - Intel S2600KPFR Product Specifications

Appendix D: POST Code Diagnostic LED Decoder

Technical Product Specification
Appendix D: POST Code Diagnostic LED Decoder
During the system POST process, Diagnostic LED Codes are used extensively as a mechanism
to indicate progress and Fatal Halt conditions independently of the video display. If the
system hangs or halts, the Diagnostic LED display can help determine the reason even when
video is not available.
These Diagnostic LEDs are equivalent to the Legacy "Port 80 POST Codes", and a Legacy I/O
Port 80 output will be displayed as a Diagnostic LED code.
The Diagnostic LEDs are a set of LEDs found on the back edge of the server board. There are 8
Diagnostic LEDs which form a 2 hex digit (8 bit) code read left-to-right as facing the rear of the
server.

Figure 52. Diagnostic LED Placement Diagram

An LED which is ON represents a 1 bit value, and an LED which is OFF represents a 0 bit value.
The LED bit values are read as Most Significant Bit to the left, Least Significant Bit to the right.
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