4.5 ATA Commands
4.5.10 SET FEATURES (EFh)
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| Table 4.31 SET FEATURES command |
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| 7 | 6 | 5 | 4 |
| 3 | 2 | 1 | 0 |
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CM | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | |
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DH | X | X | X | DEV |
| X | X | X | X |
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CH | X | X | X | X |
| X | X | X | X |
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CL | X | X | X | X |
| X | X | X | X |
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SN | X | X | X | X |
| X | X | X | X |
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SC |
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| Setting value |
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FR |
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| Setting value |
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The SET FEATURES command changes the ODD operating mode to the mode set in the SC and FR registers. If the specified value is not supported by the ODD or an invalid value, the ODD reports Aborted Command.
Table 4.32 FR register setting value
Setting | Function | Default |
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02 | Enables the write cache. | * |
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03 | Supports data transfer depending on the value of the SC register. See Table | 31 |
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31 | Disables the media status notification function. | * |
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55 | Disables the read ahead cache. |
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66 | Does not reset various setting values to the | * |
| software reset. (The media status notification function is reset normally.) |
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82 | Disables the write cache. |
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95 | Enables the media status notification function. |
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AA | Enables the read ahead cache. | * |
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CC | Returns various setting values to the |
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