4.1.3Set Features command
This command controls the implementation of various features that the drive supports. When the drive receives this command, it sets BSY, checks the contents of the Features register, clears BSY and generates an inter- rupt. If the value in the register does not represent a feature that the drive supports, the command is aborted.
Table 8: |
| Features register values | ||
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02H |
| Enable write cache (default). | ||
03H |
| Set transfer mode (based on value in Sector Count register). | ||
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| Sector Count register values: | ||
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| 00H |
| Set PIO mode to default (PIO mode 2). |
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| 01H |
| Set PIO mode to default and disable IORDY (PIO mode 2). |
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| 08H |
| PIO mode 0 |
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| 09H |
| PIO mode 1 |
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| 0AH |
| PIO mode 2 |
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| 0BH |
| PIO mode 3 |
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| 0CH |
| PIO mode 4 (default) |
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| 20H |
| Multiword DMA mode 0 |
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| 21H |
| Multiword DMA mode 1 |
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| 22H |
| Multiword DMA mode 2 |
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| 40H |
| Ultra DMA mode 0 |
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| 41H |
| Ultra DMA mode 1 |
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| 42H |
| Ultra DMA mode 2 |
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| 43H |
| Ultra DMA mode 3 |
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| 44H |
| Ultra DMA mode 4 |
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| 45H |
| Ultra DMA mode 5 |
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| |
05H |
| Enable advanced power management | ||
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55H |
| Disable read | ||
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| ||
82H |
| Disable write cache. | ||
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| ||
AAH |
| Enable read | ||
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| ||
F1H |
| Report full capacity available | ||
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Note. At
28 | Momentus 7200.1 PATA Product Manual, Rev. C |