4.5 ATA Commands

4.5.10 SET FEATURES (EFh)

 

 

Table 4.31 SET FEATURES command

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

 

 

 

 

 

 

 

 

 

 

 

 

7

6

5

4

 

3

2

1

0

 

 

 

 

 

 

 

 

 

 

CM

1

1

1

0

1

1

1

1

 

 

 

 

 

 

 

 

 

 

DH

X

X

X

DEV

 

X

X

X

X

 

 

 

 

 

 

 

 

 

 

CH

X

X

X

X

 

X

X

X

X

 

 

 

 

 

 

 

 

 

 

CL

X

X

X

X

 

X

X

X

X

 

 

 

 

 

 

 

 

 

 

SN

X

X

X

X

 

X

X

X

X

 

 

 

 

 

 

 

 

SC

 

 

 

Setting value

 

 

 

 

 

 

 

 

 

 

 

FR

 

 

 

Setting value

 

 

 

 

 

 

 

 

 

 

 

 

 

The SET FEATURES command changes the ODD operating mode to the mode set in the SC and FR registers. If the specified value is not supported by the ODD or an invalid value, the ODD reports Aborted Command.

Table 4.32 FR register setting value

Setting

Function

Default

value

 

value

 

 

 

02

Enables the write cache.

*

 

 

 

03

Supports data transfer depending on the value of the SC register. See Table

31

 

4.33.

 

 

 

 

31

Disables the media status notification function.

*

 

 

 

55

Disables the read ahead cache.

 

 

 

 

66

Does not reset various setting values to the power-on default value by

*

 

software reset. (The media status notification function is reset normally.)

 

 

 

 

82

Disables the write cache.

 

 

 

 

95

Enables the media status notification function.

 

 

 

 

AA

Enables the read ahead cache.

*

 

 

 

CC

Returns various setting values to the power-on default value by software

 

 

reset.

 

 

 

 

C156-E205-01EN

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Image 107
Fujitsu MCJ3230AP manual SET Features EFh, SET Features command, Dev, FR register setting value