Quantum LTO 4, Руководство пользователя

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SCSI Commands: 20BLOG SELECT Page 45
Field Bytes Bits Description
Parameter
List
Length 7-8 Always 0. Specifies the length (in bytes) of the parameter list to be
transferred during the Data Out phase. A 0 length indicates that no
parameter data is to be transferred.
Reserved All reserved bits must be 0.
Control 9 See SCSI Command Control Byte Format on page 25.
Note: Pages 00h, 0Ch, 0Dh, 12h, 14h, 16h, 30h, 31h, 33h and 3Eh cannot be
reset by LOG SELECT.
The drive does not maintain a separate set of log parameters for each initiator.
Therefore, a LOG SELECT command affects all initiators.
Note: The subsequent section discusses the LOG SENSE command. The log
page codes and the log parameter codes are described in that section.
3.8.2 Log Pages
A log page is made up of a four-byte page header and one or more log parameters.
A log parameter is made up of a four-byte parameter header and one or more
associated parameter data bytes.
The following table shows the log page header format.
Byte
Bits
7 6 5 4 3 2 1 0
0 Reserved Page Code
1 Reserved
2 (MSB)
3
Page Length
(LSB)
3.8.2.1 Log Page Field Descriptions
Field Bytes Bits Description
Page
Code 0 0-5 Identifies the page.
Page
Length 2-3 Indicates the length of log parameters (in bytes) that follow the page
header.
Reserved All reserved bits must be 0.
3.8.2.2 Log Parameter
The following table shows a typical log parameter format.
Byte
Bits
7 6 5 4 3 2 1 0
0 (MSB)
1
Parameter Code
(LSB)
2 DU DS Reserved
3 Parameter Length (n-3)
4 (MSB)
n
Parameter Value
(LSB)