Chapter 4 SCSI Commands
LOG SELECT Command (4Ch)
DLT-S4 Interface Reference Guide
59
Overview—
LOG SELECT
Command Descriptor
Block Errors
4
The following conditions constitute errors that the drive detects in
relation to the CDB. If the drive detects one of the conditions listed, it will
return
CHECK CONDITION
with the Sense Key set to
ILLEGAL REQUEST
and the Additional Sense Code set to
INVALID FIELD IN CDB
.
The conditions that constitute errors are:
• PCR bit is set to 1; Parameter List Length field is not set to 0.
• Both the PCR and SP bits are set to 1.
• A Parameter List Length that would cause a parameter within a valid
page to be truncated or otherwise incompletely initialized.
Operation of LOG
SELECT
4
The
LOG SELECT
command allows the initiator to modify and initialize
parameters within the logs the drive supports.
The two ways to initialize the log parameters are:
1 Set the PCR bit to 1 in the
LOG SELECT CDB
; this clears all
parameters.
2 Specify the log page and parameter values as the log parameters to
clear individual pages. The following pages can be cleared using this
method:
Table 34
LOG SELECT
Page-
clearing Codes
Page Code
Page Description
02h
Write Error Count Page
03h
Read Error Count Page
0Ch
Sequential Access Device Page
38h
General Purpose Non-Volatile Log Page
Note:
If an initiator sends multiple pages, it must send them in
ascending order according to page code. Otherwise, the drive
terminates the command with a
CHECK CONDITION
status,
Sense Key set to
ILLEGAL REQUEST
, and Additional Sense
Code set to
INVALID FIELD IN PARAMETER LIST
. The drive
returns the same status if an unsupported page code appears
in any header or if the specified page cannot be cleared.
