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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 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: 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
32 | DiamondMax 20 Serial ATA Product Manual, Rev. A |