Quantum LTO 4, Руководство пользователя

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SCSI Commands: 22BMODE SELECT Page 80
3.10.2 MODE SELECT Parameters
The MODE SELECT parameter list, for both the MODE SELECT(6) and MODE
SELECT(10) commands is in the following general format:
Mode Parameter Header The Mode Parameter Header is required.
Block Descriptor The Block Descriptor is optional.
Mode Parameter Pages Zero or more Mode Parameter Pages may be
included.
3.10.3 Mode Parameter Header
3.10.3.1 MODE SELECT(6) Parameter Header
Bits
Bytes
7 6 5 4 3 2 1 0
0 Mode Data Length
1 MEDIUM TYPE
2 WP Buffered Mode Speed
3 Block Descriptor Length
3.10.3.2 MODE SELECT(6) Parameter Header Field Descriptions
Field Bytes Bits Description
Mode Data
Length
0 MODE SELECT: Always 0.
MODE SENSE: The number of bytes of data available.
MEDIUM
TYPE 1 00h = Data medium
01h = Cleaning medium
80h = WORM medium
WP 2 7 MODE SELECT: Ignored.
MODE SENSE: 0 = The cartridge is not write protected.
1 = the cartridge is write protected.
Buffered
Mode 2 4-6 0 = Un-buffered mode.
1 = Buffered mode (default).
Speed 2 0-3 This field indicates the speed at which the tape in the cartridge
may be used. Other speeds may be supported for manufacturing
purposes.
0 = variable speed (default)
Block
Descriptor
Length 3 0 = No Block Descriptor follows.
8 = 8-byte Block Descriptor follows.
Reserved All reserved bits must be 0.
When Buffered Mode is 1, a WRITE command is completed when the data is
transferred to the internal buffer of the drive. When Buffered Mode is 0 a WRITE
command is not completed until all data has been transferred to tape.