User's Guide

Quantum Scalar Intelligent Libraries SCSI Reference Guide Guide 25
Log Sense - 4Dh
What the Library Does with This Command
The library returns information for the requested log page. The only supported log page is the Tape Alert
page, with a limited set of flags. The library will return the current values of the flags on request, and then
clear them.
Command Usage
This command can be used to monitor conditions of the library.
Log Sense CDB Format
The LOG SENSE CDB format is shown in the following table.
Parameter Pointer Control (PPC) – Must be set to 0. The library will return log parameters starting with
the parameter code specified in the Parameter Pointer field, and return up to the number of bytes specified
in the Allocation Length field. Log parameters are returned in ascending order according to their parameter
code. A PPC bit of 0 and a Parameter Pointer field of 0 will cause all available log parameters for the
requested page code to be returned, subject to the Allocation Length.
Save Parameters (SP) – Must be set to 0. The library does not support the saving of log parameters.
Page Control (PC) – Must be set to 01b. The library only returns cumulative values for any log parameter
rather than threshold or default values.
Table 20 LOG SENSE CDB format
Bit
Byte
76543210
0 Op Code (4Dh)
1 Logical Unit Number Reserved PPC SP
2 PC Page Code
3 Reserved
4 Reserved
5
Parameter Pointer
6
7
Allocation Length
8
9 Control