Host Interface
When 0 is specified as Transfer Length, data is not transferred. The command ends normally without executing Read processing.
4.6.11 READ CAPACITY command
Table 4.83 READ CAPACITY command
Bit | 7 | 6 | 5 |
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| 2 | 1 | 0 |
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0 |
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1 | Logical Unit Number |
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8 |
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The READ CAPACITY command transfers data on the media capacity to the host.
Table 4.84 lists the data transferred if the Partial Medium Indicator (PMI) bit is 0.
Table 4.84 READ CAPACITY data (PMI=0)
Bit | 7 | 6 | 5 |
| 4 | 3 |
| 2 | 1 | 0 |
Byte |
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| Last Logical Block Address |
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| Block Length in Bytes |
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Last Logical Block Address indicates the LBA of the last accessible block.
Block Length in Bytes indicates the number of bytes per block.
When the Partial Medium Indicator (PMI) bit is 1, the data to be transferred depends on the type of media. Tables 4.85 and 4.86 list the data transferred for two types of media.
Table 4.85 READ CAPACITY data (PMI=1, MO media, FROM medium)
Bit | 7 | 6 | 5 |
| 4 | 3 |
| 2 | 1 | 0 |
Byte |
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| Last Logical Block Address |
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| Block Length in Bytes |
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