SCSI Commands: 21BLOG SENSE
Page
48
3.9
LOG SENSE
The LOG SELECT and LOG SENSE commands work in conjunction to allow the
host to control and obtain statistical information about cartridge usage and error
rates. This information consists of counters of particular events.
LOG SENSE data is obtained by specifying a log page in the Page Code field of the
LOG SENSE CDB. The host can request only one page of data with each LOG
SENSE command. The available pages are found by reading the Supported Log
Pages Log (00h).
3.9.1
LOG SENSE Command Descriptor Block
Byte
Bits
7 6 5 4 3 2 1 0
0
Operation Code (4Dh)
1
Ignored LUN
Reserved
2
PC Page
Code
3
Reserved
4
Reserved
5
(MSB)
6
Parameter Pointer
(LSB)
7
(MSB)
8
Allocation Length
(LSB)
9
Control
3.9.1.1
LOG SENSE Command Field Descriptions
Field Bytes
Bits
Description
Operation
Code
0
The Operation Code for LOG SENSE is 4Dh.
Ignored
Logical
Unit
1
5-7
The LUN field is vestigial from the SCSI-1 standard and is ignored.
Page
Control
(PC)
2 6-7
00b = Requests Threshold values (always returns maximum possible
values).
01b = Requests Accumulated values.
10b = Requests Default threshold values (always returns maximum
possible values).
11b = Requests Default accumulated values (always returns 0s).
Summary of Contents for LTO 4
Page 1: ......