TEST UNIT READY COMMAND (00h)
The TEST UNIT READY command provides a method to check if the logical unit is ready. This is not a request for a
Table 14. Test Unit Ready CDB
Bit | 7 |
| 6 |
| 5 |
| 4 |
| 3 | 2 |
| 1 | 0 |
Byte |
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0 |
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| Operation Code (00h) |
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1 |
| Reserved |
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| Reserved |
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2 |
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| Reserved |
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3 |
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| Reserved |
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4 |
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| Reserved |
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5 |
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| Control |
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READ (6) COMMAND (08h)
The READ (6) command requests that the drive transfer data to the initiator. The most recent data value written in the addressed logical block shall be returned.The logical block address field specifies the logical block at which the read operation shall begin. The transfer length field specifies the number of contiguous logical blocks of data to be transferred. A transfer length of zero indicates that 256 logical blocks shall be transferred. Any other value indicates the number of logical blocks that shall be transferred. Byte 5 is ignored.
Table 15. Read (6) CDB
Bit | 7 | 6 | 5 | 4 |
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| 3 |
| 2 | 1 | 0 |
Byte |
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0 |
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| Operation Code (08h) |
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I | Logical Unit Number (RSVD) | (MSB) |
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2 |
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| Logical Block Address |
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3 |
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4 |
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| Transfer Length |
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5 |
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| Control |
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40 | ZeusIOPS |