SCSI Log Select Command
The SCSI Log Select command "provides a means for an application client to manage statistical information maintained by the SCSI target device about the target device or its logical units". The format of the CDB for the Log Select command is[1]:
bit→
↓byte |
7 |
6 |
5 |
4 |
3 |
2 |
1 |
0 |
| 0 |
Operation code = 4Ch |
| 1 |
Reserved |
PCR |
SP |
| 2 |
PC |
Page Code |
| 3 |
Subpage Code |
| 4 |
Reserved |
| 5 |
| 6 |
| 7 |
Parameter list length |
| 8 |
| 9 |
Control |
The special parameter fields in the CDB have the following meaning:
- PCR - Parameter Code Reset - setting this bit instructs the target to reset all parameters to their default values
- SP - Save Parameters - setting this bit instructs the target to save all saveable log parameters to a non-volatile memory or media area
- PC - Page Control - specifies which data counter parameter values shall be processed:
- 00 - Threshold Values
- 01 - Cumulative Values
- 10 - Default Threshold Values
- 11 - Default Cumulative Values
- Parameter List Length - in bytes
See also
References
- ^ "SCSI Primary Commands - 4 (SPC-4)" (PDF). http://www.t10.org/cgi-bin/ac.pl?t=f&f=spc4r30.pdf. Retrieved 2011-03-31.