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SONY SDT-10000/SDT-11000 DDS Tape Drive
6. COMMAND SPECIFICATION
Table 6-26: MODE SELECT Page Header
PS: when the Page Savable bit is set, this indicates that the page contains saved parameters. This bit will never be set as
there is no non-volatile RAM on the drive into which parameter data may be saved.
The page codes that are supported are:
Page Code
Description
Parameter List Length
00h
Standard Sense
0Ch
02h
Disconnect-Reconnect Page
0Ch+10h=1Ch
0Fh
Data Compression Control Page
0Ch+10h=1Ch
10h
Device Configuration Page
0Ch+10h=1Ch
11h
Medium Partitions Parameter Page
0Ch+0Ch=18h
1Ch
Information Exception Control
0Ch+0Ch=18h
3Fh
Return All Pages
0Ch+10h+10h+10h+0Ch=48h
Table 6-27: Supported MODE SELECT Page Codes
MODE SELECT
Number of Blocks:
A MODE SENSE field which will be returned as zero, indicating that all of the remaining logical blocks on the
media will have the medium characteristics specified by the block descriptor, or until a subsequent MODE SELECT
command changes those parameters. This field must be set to zero on a MODE SELECT otherwise a CHECK
CONDITION status will be returned with an ILLEGAL REQUEST sense key.
Block length:
The Block Length field specifies the length in bytes of each logical block transferred over the SCSI bus. A block
length of zero indicates that the length is variable. Any other value indicates the number of bytes per block that the
drive must handshake over the bus. This establishes block length such that the transfer length for read, write and
verify type commands will be a block count not a byte count.
Note: It is value of this field together with the Fixed Bit Field in the READ, or WRITE commands that determines
whether the drive is in Fixed or Variable block mode.
Mode
Fixed Bit in Read, Write,
Block Length in
Verify & Recover Buffered Data
Mode Select/Sense
Fixed Block
1
Block Size
Variable Block
0
0
The default fixed block size is 512 bytes however, the drive will accept a variable Write command (fixed bit of zero)
without reporting an error.
Following the Block Descriptor are the MODE SELECT pages. They are the method by which the device parameters
are set. Each page has a two byte header which identifies the page code and indicates the number of bytes in that page.
Bit
7
6
5
4
3
2
1
0
Byte
0
PS
Reserved
Page Code
1
Additional Page Length
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