Quantum DLT 2000, Руководство по эксплуатации продукта

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DLT2000 SCSI Interface
DLT2000/DLT2700 Cartridge Tape Subsystem 8-53
8.4.9.4 Data Compression Page (0Fh)
The Data Compression Page specifies parameters for the control of data compression.
This page allows you to turn DLT2000 compressed format on and off independently of
the tape's position and allows you to enable or disable decompression of DLT2000
compressed data during write operations.
Bit
7 6 5 4 3 2 1 0
0 RSVD
Page Length
DCE DCC Reserved
Byte RED Reserved
Compression Algorithm
(LSB)
Decompression Algorithm
11
Page Code
1
Reserved
DDE
(LSB)
12
15
2
(MSB)
3
(MSB)
4
7
8
Figure 8-33 Data Compression Page (0Fh)
Page Code
The Page Code identifies the type of MODE SELECT page being transferred. This is
the Data Compression Page. The valid value for the Page Code is (0Fh).
Page Length
The Page Length indicates the number of bytes in the Data Compression Page that
follow this byte. The valid value for this byte is (0Eh).
DCE (Data Compression Enable)
The Data Compression Enable bit specifies whether the DLT2000 should enable or
disable data compression. When the DCE bit is 1, the DLT2000 starts in compressed
format.
DCC (Data Compression Capable)
The Data Compression Capable bit is used by the MODE SENSE command to indicate
that the DLT2000 supports data compression.