HP Surestore 28/48-Slot with DLT7000 Digital Linear Tape SCSI-2 Drive and SCSI - Page 283

Additional Considerations, Modifying the Tape Driver for the Library, Load/Unload, Erase, Verify

Page 283 highlights

Table B-3 Programmer's Tips Modifying the SCSI Driver Additional Considerations The following commands may be needed depending on the intended application. Load/Unload: Used in conjunction with moving tapes in and out of the drives for loading and unloading the tape Erase: Use for applications to pre-erase an entire tape Verify: Used for applications that require an extra level of data verification. A second pass is done to reread the tape that is causing performance degradation Modifying the Tape Driver for the Library The driver that interacts with the library can be an extension to the tape driver or a separate driver, depending on the architecture of the I/O subsystem. For library functionality, the following SCSI commands need to be supported by the driver: Necessary Autochanger SCSI Commands Command OP Code Must Support Initialize Element Status Inquiry Move Medium Read Element Status Request Sense Test Unit Ready 07H 12H A5H B8H 03H 00H Appendix B B- 13

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Appendix B
B-13
Programmer’s Tips
Modifying the SCSI Driver
Additional Considerations
The following commands may be needed depending on the intended
application.
Load/Unload
: Used in conjunction with moving tapes in and out of the
drives for loading and unloading the tape
Erase
: Use for applications to pre-erase an entire tape
Verify
: Used for applications that require an extra level of data
verification. A second pass is done to reread the tape that is causing
performance degradation
Modifying the Tape Driver for the Library
The driver that interacts with the library can be an extension to the tape
driver or a separate driver, depending on the architecture of the I/O
subsystem. For library functionality, the following SCSI commands need
to be supported by the driver:
Table B-3
Necessary Autochanger SCSI Commands
Command
OP Code
Must Support
Initialize Element Status
07H
Inquiry
12H
Move Medium
A5H
Read Element Status
B8H
Request Sense
03H
Test Unit Ready
00H