Quantum LTO 4, Руководство пользователя

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SCSI Commands: 32BREAD POSITION Page 146
3.20.2 READ POSITION Data
The READ POSITION command returns a block of READ POSITION Data.
The following table shows the fields in the READ POSITION Data when the Long
and TCLP bits are set to zero.
Byte Bits
7 6 5 4 3 2 1 0
0 BOP EOP Reserved BPU Reserved
1 Partition Number (0)
2 Reserved
3 Reserved
4 (MSB)
5
6
7
First Block Location
(LSB)
8 (MSB)
9
10
11
Last Block Location
(LSB)
12 Reserved
13 (MSB)
14
15
Number of Blocks in Buffer
(LSB)
16 (MSB)
17
18
19
Number of Bytes in Buffer
(LSB)
3.20.2.1 READ POSITION Short Form Field Descriptions
Field Bytes Bits Description
BOP 0 7 0 = The current logical position is not at BOP.
1 = The current logical position is at Beginning-of-Partition (BOP).
EOP 0 6 0 = The current logical position is not between early warning and
end-of-tape.
1 = The current logical position is between early warning and end-
of-tape.
BPU 0 2 0 = First Block Location and Last Block Location fields are valid.
1 = First Block Location and Last Block Location fields are invalid.
Partition
Number 1 This field is always 0.
First Block
Location 4-7 The block address of the current logical position.
Last Block
Location 8-11 The block address of the current logical position. Always the same
as First Block Location.