Seagate (ST8000VN004) - Инструкция по эксплуатации - Страница 31

Seagate IronWolf SATA Product Manual, Rev. B

  30

4.3.2

Set 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 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

Table 9

Set Features command values

02

H

Enable write cache 

(default).

03

H

Set transfer mode (based on value in Sector Count register).

Sector Count register values:

00

H

Set PIO mode to default (PIO mode 2).

01

H

Set PIO mode to default and disable IORDY (PIO mode 2).

08

H

PIO mode 0

09

H

PIO mode 1

0A

H

PIO mode 2 

0B

H

PIO mode 3

0C

H

PIO mode 4 

(default)

20

H

Multiword DMA mode 0

21

H

Multiword DMA mode 1

22

H

Multiword DMA mode 2

40

H

Ultra DMA mode 0

41

H

Ultra DMA mode 1

42

H

Ultra DMA mode 2

43

H

Ultra DMA mode 3

44

H

Ultra DMA mode 4

45

H

Ultra DMA mode 5

46

H

Ultra DMA mode 6

10

H

Enable use of SATA features

55

H

Disable read look-ahead (read cache) feature.

82

H

Disable write cache

90

H

Disable use of SATA features

AA

H

Enable read look-ahead (read cache) feature 

(default).

F1

H

Report full capacity available

Note

At power-on, or after a hardware or software reset, the default values of the features are as indicated above.