Fujitsu MAP3735 Computer Drive User Manual


 
Sense Data Error Recovery Methods
5 - 14 C141-E167
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 4.4.)
0 x x No sense data showing the error contents are held. None 4
11300S
y
nc b
y
te not found for data field Need 8
15 xx Positioning error
17 xx Recovered error without ECC
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
p
arameter None 9
The IDD's rounding processing was applied to the
MODE SELECT parameters specified by the INIT.
20401Lo
g
ical unit not read
y
Need
** 10**
The logical unit specified by the command is in a
state where it cannot be accessed.
02 Logical unit not ready
20404Lo
g
ical unit not read
y
, format in
p
ro
g
ress None 11
The logical unit specified by the command is
currently being formatted, so access is impossible.
Peri
p
heral device write fault Need 730C03
Unrecovered write offtrack error
The maximum number of write offtrack retries was
reached when AWRE = 0.
* K: Sense Key C: Sense Code
Q: Sub-sense code 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.