Fujitsu M2488, Руководство по эксплуатации продукта

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M2488 PRODUCT GUIDE TAPE UNIT SCSI COMMANDS
April 1997 CG00000-011503 REV. A 4-15
4-3.5 ERASE command 19h
The ERASE command causes part or all of the remaining medium to be erased beginning from the
current logical position.
After the receipt of a valid ERASE command, tape synchronization is performed prior to execution
of the ERASE operation. If tape is positioned at BOT, the ERASE command will cause an ID area to
be written before the Erase operation.
4-3.5.1 ERASE CDB Description
ERASE is a six-byte command as shown below and described in Table 4-14. Common fields are
described in paragraph 4-3.1 on page 4-4.
BITS
BYTES 7 6 5 4 3 2 1 0
0 0 0 0 1 1 0 0 1
1 LUN Reserved Immed Long
2 Reserved
3 Reserved
4 Reserved
5 Reserved Flag Link
Note: Changeable fields in the CDB are shaded.
Table 4-14. ERASE Field Description
BYTE BIT VALUE DESCRIPTION
0 0-7 19h Operation code.
1 0 0
1 If Long bit=0, Erase gap.
If Long bit=1, Data security erase.
1 0-1 The Immediate (Immed) bit controls the time at which status is to be returned.
Actions taken by the target depend on the settings of the Immed and Long bits as
described in the next table.
IMMED BIT LONG BIT ACTION TAKEN
0 Don’t care Status is returned after the Erase operation is complete.
1 0 Status is returned after the CDB is validated. *
1 1 Status is returned after all previously buffered commands are
completed and the CDB is validated. *
* If a CHECK CONDITION status is returned for this case, the ERASE operation is not performed.