SCSI Log Select Command
The SCSI Log Select command is used to modify data in the log pages of a SCSI target device. The CDB structure for the Log Select command is:
bit→ |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
|---|---|---|---|---|---|---|---|---|
0 |
Operation code = 4Ch |
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1 |
LUN |
Reserved |
PCR |
SP |
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2 |
PC |
Page code |
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3 |
Reserved |
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4 |
Reserved |
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5 |
Reserved |
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6 |
Reserved |
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7–8 |
Parameter pointer |
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9–10 |
Parameter list length |
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11 |
Control |
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The special parameter fields in the CDB have the following meaning:
- PCR - Parameter Code Reset - if this is one then all parameter codes will be reset to their default values
- SP - Save Parameters - if this is one then the target should save all saveable log parameters to a non-volatile memory or media area
- PC - Page Control - this indicates which type of values will be sent:
- 00 - Threshold Values
- 01 - Cumulative Values
- 10 - Default Threshold Values
- 11 - Default Cumulative Values
- Parameter List Length - in bytes
- Page Code - this indicates which log page will be selected:
- 00 - List of supported log pages
- 01 - buffer overrun
- 02 - write error counters
- 03 - read error counters
- 05 - verify error counters