Fujitsu 80, Спецификации логического интерфейса SCSI

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5.2 INIT Error Recovery Methods (Recommended)
C141-C010 5-15
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.
Table 5.3 Sense data error classification (1 of 4)
K* C* Q* Outline of Error L*
Recovery Method
(See Table 5.4.)
0 x x No sense data showing the error contents are held. None 4
1 13 00 Sync byte not found for data field Need 8
15 xx Positioning error
17 xx Recovered data without ECC
18 xx Recovered data with error correction applied.
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.
1 37 00 Rounded parameter None 9
The IDD's rounding processing was applied to the
MODE SELECT parameters specified by the INIT.
2 04 01 Logical unit not ready
Need
** 10**
The logical unit specified by the command is in a
state where it cannot be accessed.
02 Logical unit not ready
2 04 04 Logical unit not ready, format in progress None 11
The logical unit specified by the command is
currently being formatted, so access is impossible.
3 03 xx Peripheral device write fault Need 7
Write error recommend reassignament 0C 03
Unrecoverred write error
* K: Sense Key C: Additional Sense Code
Q:
Additional Sense Code Qualifier
L: Logging Necessary? (shown in Section 5.2.3)
** 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.