Table 54 Feature Control Command (Inputs); Table 55 Feature Control Command (Outputs) - Hitachi HDS723020BLA642 Specifications

9.18.3.3
Feature Control Command (action code : 0004h)
Inputs: (Key Sector)
Word Name
0 Action Code
1 Function Code
2 Feature Code
3 State
4 Option Flags
255:5 reserved

Table 54 Feature Control command (Inputs)

Outputs: (TF Data)
Command Block Input Registers (Success)
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status

Table 55 Feature Control command (Outputs)

Value Description
0004h Set or return the state of drive features described in 0
0001h Set state for a feature
0002h Return the current state of a feature
0003h Return feature option flags
Word See 0 for a list of the feature codes
Word Feature code dependent value
Word Bit15:1 = Reserved
If the function code is 0001h, setting bit 0 to one causes the
requested feature state change to be preserved across
power cycles.
If the function code is 0001h, setting bit 0 to zero causes the
requested feature state change to be volatile. A hard reset
causes the drive to revert to default, or last non-volatile
setting.
0000h
If Function Code was 0002h, then this is the LSB of Feature State.
If Function Code was 0003h, then this is the LSB of Option Flags.
Otherwise, this field is reserved.
If Function Code was 0002h, then this is the MSB of Feature State.
If Function Code was 0003h, then this is the MSB of Option Flags.
Otherwise, this field is reserved.
Hitachi hard disk drive specifications
00h
reserved
reserved
reserved
50h
97