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5.20READ BUFFER Command (3Ch)
The READ BUFFER command is used in conjunction with the WRITE BUFFER command. It allows the initiator to gain access to the data storage areas within the drive's controller. In particular, these two commands are used to check the integrity of the
Both the READ BUFFER and the WRITE BUFFER commands have a buffer ID and a buffer offset data field defined in their Control Descriptor Block. In the Combined Header and Data Mode, if both are set to 0, reference is made to a single
Table
Bit | 7 | 6 |
| 5 | 4 |
| 3 | 2 |
| 1 | 0 |
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0 |
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| Operation | Code (3Ch) |
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1 |
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| Reserved |
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| Mode |
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2 |
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| Buffer ID |
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3 - 5 |
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| Buffer Offset |
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6 - 8 |
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| Allocation Length |
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9 |
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| Control |
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