5.18READ (6) Command (08h)
The READ (6) command requests that data be transferred from the drive to the initiator. The amount of data transferred is specified by the transfer length field. The starting point is specified by the logical sector address. The data format and field descriptions are shown in Table
Table
Byte | Bit | 7 | 6 | 5 |
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| 3 | 2 | 1 | 0 |
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0 |
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| Operation | Code (08h) |
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1 |
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| Reserved |
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| Logical Block Address |
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2 - 3 |
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| Logical Block Address (continued) |
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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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Table
Field | Description | |
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Logical Block Address | Specifies the logical block address where the read operation | |
will begin. | ||
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| Specifies the number of contiguous logical blocks of data to | |
Transfer Length | transfer. A transfer length of 0 indicates that 256 logical | |
blocks will be transferred. Any other value indicates the | ||
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| number of logical blocks that will be transferred. | |
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