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4.3.2Set Features command
This command controls the implementation of various features that the drive supports. When the drive receives this com- mand, it sets BSY, checks the contents of the Features register, clears BSY and generates an interrupt. If the value in the register does not represent a feature that the drive supports, the command is aborted.
Table 7: Set Features command values
02H | Enable write cache (default). | |
03H | Set transfer mode (based on value in Sector Count register). | |
| Sector Count register values: | |
| 00H | Set PIO mode to default (PIO mode 2). |
| 01H | Set PIO mode to default and disable IORDY (PIO mode 2). |
| 08H | PIO mode 0 |
| 09H | PIO mode 1 |
| 0AH | PIO mode 2 |
| 0BH | PIO mode 3 |
| 0CH | PIO mode 4 (default) |
| 20H | Multiword DMA mode 0 |
| 21H | Multiword DMA mode 1 |
| 22H | Multiword DMA mode 2 |
| 40H | Ultra DMA mode 0 |
| 41H | Ultra DMA mode 1 |
| 42H | Ultra DMA mode 2 |
| 43H | Ultra DMA mode 3 |
| 44H | Ultra DMA mode 4 |
| 45H | Ultra DMA mode 5 |
| 46H | Ultra DMA mode 6 |
10H | Enable use of SATA features | |
55H | Disable read | |
82H | Disable write cache | |
90H | Disable use of SATA features | |
AAH | Enable read | |
F1H | Report full capacity available | |
Note. | At |
Barracuda XT Series SATA Product Manual, Rev. C | 27 |