MODE SELECT 15h/55h
Commands
91
Information Exceptions mode page
The Information Exceptions Mode page is used to control exception reporting through the
“TapeAlert log page” on page 65:
7 6 5 4 3 2 1 0
0 PS (0) Rsvd (0) Page Code {1Ch}
1 Page Length {0Ah)
2 Perf (0) Reserved (0) DExcpt Test Rsvd (0) LogErr (0)
3 Reserved (0) MRIE (3h)
4 (MSB)
Interval Timer (0)
7 (LSB)
8 (MSB)
Report Count/Test Flag Number
11 (LSB)
Perf 0 Informational exception operations that cause delays are acceptable.
DExcpt Disable Exception Control. It must be zero when the Test Flag Number is zero. When
the Test Flag Number contains a valid non-zero value, the DExcpt flag can be 0 or 1.
0 Information exception operations are enabled. The reporting of information
exception conditions is determined from the MRIE field.
1 A DExcpt bit of one indicates the target will disable all information exception
operations. The method of reporting informational exceptions field is ignored
when DExcpt is set to one. The Test bit must not be set at the same time.
Test 0 If the Test flag is clear the next command will be processed normally.
1 A test bit of one will generate false informational exception conditions. As a
result, the next SCSI command after the Mode Select will return CHECK
CONDITION with a sense key of RECOVERED ERROR and additional sense of
5DFFh (failure prediction threshold exceeded - false). The DExcpt bit must not be
set at the same time.
The Test bit will never be read as 1 when performing a Mode Sense command. This
is not an indication that the drive is in test mode.
For example, using the Test bit and Test Flag Number, it may be possible to set a flag
with the DExcpt bit set to 1. When the DExcpt bit is next set, the drive will report
CHECK CONDITION with a sense key of RECOVERED ERROR and additional sense
of 5DFFh (failure prediction threshold exceeded - false). In order to set the DExcpt bit
again, note that the Test bit must still be set during the Mode Select command.
LogErr 0 Log Errors bit. This bit must be zero, indicating that the logging of informational
exception conditions within the drive is vendor-specific.
