Chapter 5 Initiator Mode |
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Initiator | Page 5 - 17 |
Selectable Sense Bytes
You also have the option to select which (up to 16) of the 256 possible Sense bytes be returned in the Status Block and in what order they should appear.
•The Unit Options command allows you to choose 8 selectable Sense Bytes.
•The Extended Unit Options command allows you to choose 16 selectable Sense Bytes. You will receive multiple Status Blocks.
You can specify Selectable Sense Bytes by placing a zero in the Sense Count field and filling each of the Selected Sense fields with the Sense Byte number you wished returned in that field.
For example, the Sense Bytes fields of a Status Block could return the following Sense Bytes in the following order if the Extended Unit Options command had been used.
| Byte Memory Offset |
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Offset + 0 | Offset + 1 | Offset + 2 | Offset + 3 |
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| Command Identifier |
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Reserved | SCSI Status | Error | Flags |
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0 | 1 | 2 | 3 | Sense Byt | |
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| in Status | |
4 | 5 | 6 | 7 | ||
Block #1 | |||||
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| Command Identifier |
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Reserved | SCSI Status | Error | Flags |
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56 | 57 | 12 | 19 | Sense Byt | |
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| in Status | |
122 | 33 | 12 | 23 | ||
Block #2 |
Table 42: Example of Selected Sense Bytes
Status Block #1 contains the first eight bytes with the Info Bytes arranged from LSB to MSB, and Status Block #2 returns Sense Bytes that are selected from among the other 248 Sense Bytes, based on information in the
See Chapter 7 for more information about the Unit Options and Extended Unit Options commands and how to
User’s Guide | 21020285 D |