Command Descriptor Block; Data Compression; Write From Bop - Tandberg Data SLR7-140 PROGRAMMER Manual

BYTE BIT 7
00 Operation Code 0Ah
01 Logical Unit Number (LUN)
02 Transfer Length
03
04
05 RESERVED
Table 30-1:
FIX
Transfer Length
Tandberg Data

30.2. Command Descriptor Block

6 5
WRITE Command Descriptor Block
A Fixed (FIX) bit of zero indicates that a single block
will be transferred with the Transfer Length specifying
the length of the block in bytes. A FIX bit of one
indicates that the Transfer Length specifies the number
of fixed length
Initiator.
This field specifies
requested for transfer. Any value in the range 0..262144
is legal when the FIX bit is set to zero. When the FIX
bit is set to one any value in the range 0..16777215 is
legal.

30.3. Data Compression

The Drive is able to compress the data before it is
written to the medium. The compression capability is
controlled by parameters in the Data Compression Page of
the MODE SELECT command. Compression may here be turned
on or off.

30.4. Write from BOP

Write from BOP is allowed:
when the Write command is the first medium access
command executed on a newly inserted cartridge. If
the partition number is not explicitly changed, the
Drive will start writing on partition zero.
after an ERASE, LOAD (with Load bit set to one) or
REWIND command. Refer to the corresponding command
description for the partition number.
after a SPACE or LOCATE command which terminated with
CHECK CONDITION and Error Code set to B
/
PARTITION MEDIUM DETECTED
when the tape is logically positioned at BOP after a
successful SPACE or LOCATE command.
30-2 Tandberg SLR Product Line SCSI Functional Specifications
4 3
RESERVED
blocks to be
the number
.
2 1
FLAG LINK
transferred from
of bytes or blocks
-
EGINNING OF
Write
0
FIX
the
-