Freecom FC TapeWare AIT-450i, Руководство пользователя

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MODE SELSECT 6.Command Specification
SONY AIT-1 Turbo drive SDX-450V series Ver.1.0 6-37
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 & Verify Block Length in
Mode Select/Sense
Fixed Block
Variable Block 1
0 Block Size
0
The default fixed block size is 512 bytes however, the drive will accept a variable command (fixed bit of ZERO)
without reporting an error.
Note: Minimum block-size is 2. If a non ZERO block-size is 1, CHECK CONDITION status will be return, and Sense
Key will be ILLEGAL REQUEST.
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.
Table 6-33: MODE SELECT Page Header
Bit
Byte
7 6 5 4 3 2 1 0
0 PS Reserved Page Code
1 Additional Page Length
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:
Table 6-34: Supported MODE SELECT Page Codes
Page Code Description Parameter List Length
00h
02h
0Fh
10h
11h
1Ch
Standard Sense
Disconnect-Reconnect
Data Compression Control
Device Configuration
Medium Partitions Parameter
Information Exception Control 0Ch
0Ch+10h=1Ch
0Ch+10h=1Ch
0Ch+10h=1Ch
0Ch+0Ch=18h ( when AIT bit is ZERO )
0Ch + (8+2 xn) =14h + 2xn(when AIT bit is ONE )
0Ch+0Ch=18h
31h
32h
33h AIT Device Configuration
Append Partition
Delete Partition 0Ch+0Ah=16h
0Ch+0Ah=16h ( only when AIT bit is ONE )
0Ch+0Ah=16h ( only when AIT bit is ONE )
3Fh Return All Pages
0Ch+10h+10h+10h+0Ch+0Ah=5Eh
0Ch+10h+10h+10h+(8+2xn)+0Ch+0Ah+0Ah+0Ah=6Eh+2xn
n: Partition Number