SEAGATE 600 SSD PRODUCT MANUAL, REV. A 30 4.3.2 Set Features commandThis 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 interrupt. If the value in the register does not represent a feature that the drive supports, the command is aborted. Power-on default has the read look-ahead and write caching features enabled. The acceptable values for the Features register are defined as follows:Note. At power-on, or after a hardware or software reset, the default values of the features are as indicated above.
Table 9 Set Features command values
02HEnable write cache (default).
03HSet transfer mode (based on value in Sector Count register).
Sector Count register values:
00HSet PIO mode to default (PIO mode 2).
01HSet PIO mode to default and disable IORDY (PIO mode 2).
08HPIO mode 0
09HPIO mode 1
0AHPIO mode 2
0BHPIO mode 3
0CHPIO mode 4 (default)
20HMultiword DMA mode 0
21HMultiword DMA mode 1
22HMultiword DMA mode 2
40HUltra DMA mode 0
41HUltra DMA mode 1
42HUltra DMA mode 2
43HUltra DMA mode 3
44HUltra DMA mode 4
45HUltra DMA mode 5
46HUltra DMA mode 6
10HEnable use of SATA features
02HDMA Setup FIS Auto-Activate optimization
03HDevice-initiated interface power state transitions
06HSoftware Settings Preservation
55HDisable read look-ahead (read cache) feature
66HDisable reverting to power-on defaults
82HDisable write cache
90HDisable use of SATA features
02HDMA Setup FIS Auto-Activate optimization
03HDevice-initiated interface power state transitions
06HSoftware Settings Preservation
AAHEnable read look-ahead (read cache) feature (default).
CCHEnable reverting to power-on defaults