The error classification process involves looking up each of the errors in a frame to determine if any of them are essential. If one or more are identified as essential, the entire event is considered essential.
With error classification enabled, the general form of the report for a correctable, non-essential event is:
SC 08
CLA
END
FC 00 Bit 6, essential is cleared
With error classification enabled, the general form of the report for a correctable, essential event is:
SC 08
CLA
{classification list}
END
FC 40 Bit 6, essential is set
The {classification list} is one or more lines providing the word in frame and bit in word of each essential bit. This is the same notation used for the error detection report. Each line of the list is formatted as follows:
WD {2-digit hex value} BT {2-digit hex value}
With error classification disabled, no detailed classification list is generated. All errors must be considered essential because the controller has no basis to indicate otherwise. The general form of the report for a correctable event is:
SC 08
FC 40 Bit 6, essential is set
All uncorrectable errors must be considered essential because the controller has no basis to indicate otherwise. The general form of the report for an uncorrectable event is:
SC 08
FC 60 Bit 6, essential is set