Sense Data Analysis And Error Recovery Methods; Table 5.3 Sense Data Error Classification - Fujitsu MAX3073NC - SCSI,80, Dell DC961,Hard Drive Scsi Logical Interface Specifications

The cause of this error is the occurrence of an unrecoverable error on the SCSI bus, the occurrence of a
serious protocol error, etc. For details concerning the causes of errors, see Chapter 3, "SCSI Bus Error
Recovery Processing" in Chapter 3 of the "SCSI Physical Specifications." When this error is detected,
the INIT should issue the REQUEST SENSE command and gather sense data then judge the error
recovery method according to the contents of the sense data (see Section 4.2.2).
5.2.2

Sense data analysis and error recovery methods

The INIT can judge the procedure for error recovery by analyzing the contents of the sense data fetched
by the REQUEST SENSE command. Table 5.3 the classifications of error information displayed in the
sense data are shown and in Table 5.4, the procedures for error recovery recommended for the INIT to
execute are shown. The error recovery procedure which can be executed by the INIT will differ
depending on the system's condition, so the optimum processing procedure should be selected for the
user system with reference to the following descriptions.
K* C* Q*
0 x x No sense data showing the error contents are held.
1 13 00 Sync byte not found for data field
15 xx Positioning error
17 xx Recovered data without ECC
18 xx Recovered data with error correction applied.
1 37 00 Rounded parameter
2 04 01 Logical unit not ready
02 Logical unit not ready
2 04 04 Logical unit not ready, format in progress
3 03 xx Peripheral device write fault
0C 03 Write error recommend reassignament
* K: Sense Key
Q:
Additional Sense Code Qualifier
** Except within the time required for the disk drive to reach the ready state (approx. 20 seconds) after the
power has been switched on, or after a start instruction has been executed by the START/STOP UNIT
command.
C141-C010
Table 5.3 Sense data error classification (1 of 4)
Outline of Error
These errors are errors detected during accessing of
the disk media, but they are recovered from
through the IDD's retry processing. However,
when "1" is specified in the DTE flag in the
MODE SELECT parameters, the command may
not necessarily be executed until it is completed.
The IDD's rounding processing was applied to the
MODE SELECT parameters specified by the INIT.
The logical unit specified by the command is in a
state where it cannot be accessed.
The logical unit specified by the command is
currently being formatted, so access is impossible.
Unrecoverred write error
C: Additional Sense Code
L: Logging Necessary? (shown in Section 5.2.3)
5.2 INIT Error Recovery Methods (Recommended)
L*
None
Need
None
Need
None
Need
Recovery Method
(See Table 5.4.)
4
8
9
** 10**
11
7
5-15