Host Interface
4.3.8 RELEASE command
Table 4.40 RELEASE command
Bit | 7 | 6 | 5 |
| 4 |
| 3 |
| 2 | 1 | 0 |
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0 |
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| Operation Code (17h) |
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1 |
| LUN |
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| Reserved |
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| Reserved |
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The RELEASE command releases the ODD reserved by the INIT that issued this command. When any of the following conditions is met, the command ends with GOOD status but it does not affect the reserved status of the ODD:
•The reserved status created by the INIT that has issued this command is not in the ODD.
•The reserved status of the type of release target specified by CDB of this command is not in the ODD.
•The specified ODD may is reserved for another SCSI device.
Any values specified for CDB bytes 1 to 5 are ignored. However, INIT should specify 00h for these bytes.
In terms of the entire ODD (logical unit), the RELEASE command releases any reserved status for which the INIT that issued the command has reservation authority.
4.3.9 REQUEST SENSE command
Table 4.41 REQUEST SENSE command
Bit | 7 | 6 | 5 |
| 4 |
| 3 |
| 2 | 1 | 0 |
Byte |
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0 |
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| Operation Code (03h) |
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1 |
| LUN |
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| Reserved |
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| Reserved |
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4 |
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| Allocation Length |
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5 |
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The REQUEST SENSE command transfers sense data to the INIT. Sense data indicates detailed error information related to the command for which an error was previously reported. If no error was previously reported for a command, Sense Key indicates NO SENSE.
When issuing the REQUEST SENSE command to detect the device status, first issue the TEST UNIT READY command, then issue the REQUEST SENSE command.
Allocation Length specifies the length of sense data to be transferred, in bytes. If 0 is specified, the command does not transfer any data and ends normally.
