IBPI Spec: SGPIO Interpretation
There are 3 bits per slot (or hard drive) in the SGPIO specification. This section describes how each of these bits are interpreted according to the IBPI specification.
Only the activity bit is interpreted independently of the two other bits. The two other bits (locate and fail) may be interpreted in combination with each other in the special case when both bits are driven solid on. In any other case, the locate and fail bits are interpreted independently.
Note that the interpreted conditions described in this section is only used to determine the condition of bits, and does not describe how LEDs are driven based on these conditions. This is described in the section LED Blinking Pattern Interpretation.
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