Field | Description |
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Logical Block Address | The |
| Block Address. The |
| Block Address. |
| Commands that require additional parameter data specify the length of the Logical Block Ad- |
| dress that is needed. See the specific command descriptions for more detailed information. |
| Relative Addressing indicates a technique used to determine the next Logical Block Address to |
| be operated on. The drive does not support Relative Addressing, it defaults to a value of 0, |
| which specifies that the Logical Block Address specifies the first logical block of a range of logical |
| blocks to be operated on by the command. |
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Transfer Length | The transfer length field normally specifies the number of sectors to be transferred between the |
| initiator and the drive. For several commands, the transfer length indicates the number of bytes |
| (not sectors) to be sent. For these commands, this field may be identified by a different name |
| Commands that use one byte for the transfer length value allow up to 256 sectors of data to be |
| transferred by one command. A transfer length value of 0 indicates that 256 sectors are to be |
| sent. Transfer length values of 1 through 255 indicate the number of sectors to be transferred. |
| Commands that use multiple bytes for the transfer length value function differently. A transfer |
| length value of 0 indicates that no data transfer is to occur. Transfer length values of 1 or greater |
| indicate the number of sectors to be transferred. |
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Parameter List Length | The Parameter List Length is used to specify the number of bytes sent during the |
| transfer. This field is typically used for parameters that are sent to a drive (for example, mode, |
| diagnostic, and log parameters). A parameter list length of 0 indicates that no data is to be trans- |
| ferred. |
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Allocation Length | The Allocation Length field specifies the maximum number of bytes that the initiator has allo- |
| cated for returned data. The Allocation Length is used to limit the amount of data returned to |
| the initiator. |
| An Allocation Length of 0 indicates that no data is to be transferred from the drive to the initi- |
| ator. The drive terminates the |
| been transferred to the initiator or when all available data has been transferred, whichever is less. |
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Control Field | The Control Field is the last byte of every Command Descriptor Block; its format is shown in |
| Figure |
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Table
Bit | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | |
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5 | Vendor Specific |
| Reserved |
| NACA | Flag | Link | ||
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Maxtor Atlas 10K V |