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After SCSI BUS Reset:
P0
Device
ODA
Area
Stand by here
Note 1:
The EOT bit is effective in both DDS and AIT modes. If the EOT bit is set to ONE (as a result of the
Unload command) for an AIT mode cassette, then the drive shall wind the tape to PEOT and then unload
the tape without searching the Option Device Area. After rewinding the tape, SDX-550V will set the
Partition ID of Eject Status to 255, clear other parameters, set Reel Diameter to true values, and finally
eject the cassette.
Note 2:
Tape will be rewind to top when you issued LOAD/ UNLOAD SCSI command right after the loading
sequence by using an ODA.
14.6. Application Notes
14.6.1. Backup Techniques with MIC Cassettes
An application may choose to combine the traditional method of marking session boundaries with filemarks and
setmarks together with a new method of creating such boundries using multi-partitioning. For example, smaller
sessions may be delineated with filemarks and/or setmarks, while the application may use the Partition Append
operation to separate larger sessions-or periodically after several smaller sessions. This method should improve
access times because the drive will be able to load/unload at partition boundaries in closer porximity to desired target
locations on tape. In order to make the correct decision as to whether to use marks tor to append a partition, the
application should measure the current physical location on tape. Physical tape length can be calculated from log
(Log Sense/MIC): (Absolute Frame Number+Rewritten Frame Count)-* horizontal frame width. The idea is to strike a
balance between the need for faster access and the overhead imposed by partitioning: too many partitions will
reduce the tape capacity and consume significant amount of time to create, while too few partitions might not
optimize future access times as much as possible.
14.6.2. How to Change Active Partition
You can change partitions with Mode Select Page 10h (Device Configuration Page). Set CAP (Change Active
Partition) bit to ONE and set the destination in the Active Partition field.
14.6.3. Retention
If the Retention bit in the Load/Unload SCSI CDB is set, the drive winds to EOM, and then rewinds to BOM before
starting a loading sequence. After this sequence, drive becomes ready at partition ZERO.
SONY AIT-2 Turbo drive SDX-550V series Ver.1.0
P1
P2
ODA
ODA
Read or Write
14. Appendix G
P3
ODA
14-3
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