Informational Exceptions Control Page (1Ch) - Seagate SCSI Interface Product Manual

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5.12.13

Informational Exceptions Control page (1Ch)

The Informational Exceptions Control page (Table 102) defines the methods used by the target to control the
reporting and the operations of specific informational exception conditions. This page shall only apply to infor-
mational exceptions that report an additional sense code of Failure Prediction Threshold Exceeded to the
application client.
Informational exception conditions occur as the result of vendor specific events within a target. An informational
exception condition may occur asynchronous to any commands issued by an application client.
Mode page 1Ch may be used by the drive to implement the S.M.A.R.T. system. S.M.A.R.T. is an acronym for
Self-Monitoring Analysis and Reporting Technology. The intent of the S.M.A.R.T. system is to recognize condi-
tions that indicate imminent drive failure, and provide sufficient warning to the host system of impending failure.
Thus the host system may perform data backup before it is too late.
Table 102: Informational Exceptions Control page (1Ch)
Bit 7
Byte
0 PS
1 Page Length (0Ah)
2 Perf [1]
Changeable [10]
3
Changeable [10]
4 (MSB)
5
6
7
Changeable [10]
8 (MSB)
9
10
11
Changeable [10]
Notes.
[1] A Performance (Perf) bit of zero indicates that informational exception operations that are the cause of
delays are acceptable. A Perf bit of one indicates the target shall not cause delays while doing informa-
tional exception operations. A Perf bit set to one may cause the target to disable some or all of the infor-
mational exception operations, thereby limiting the reporting of informational exception conditions.
[2] A Disable Exception Control (DExcpt) bit of zero indicates the failure prediction threshold exceeded
reporting shall be enabled. The method of reporting the failure prediction threshold exceeded when the
DExcpt bit is set to zero is determined from the Method of Reporting Informational Exceptions field. A
DExcpt bit of one indicates the target shall disable reporting of the failure prediction threshold exceeded.
The Method of Reporting Informational Exceptions field is ignored when DExcpt is set to one and EWasc
is set to zero.
[3] An Enable Warning (EWasc) bit of zero indicates the target shall disable reporting of the warning. The
Method of Reporting Informational Exceptions field is ignored when DExcpt is set to one and EWasc is set
to zero. An EWasc bit of one indicates warning reporting shall be enabled. The method for reporting the
warning when the EWasc bit is set to one is determined from the Method of Reporting Information Excep-
tions field.
6 5
Page Descriptor Header
Reserved
Informational Exceptions Control Parameters
Reserved
Reserved
SCSI Interface Product Manual, Rev. J
4 3
Page Code (1Ch)
EWasc [3] DExcpt [2]
Interval Timer [7] [9]
Report Count [8] [9]
2 1
Test [4] Reserved LogErr [5]
MRIE [6]
0
(LSB)
(LSB)