User manual

Hitachi hard disk drive specifications
85
9.18.2.1.3 Key Sector Format
An SCT command (Key Sector) is always 512 bytes long. Table below shows the generic format of an SCT
command.
Byte
Field
Words
Description
1:0
Action Code
1
This field defines the command type and
generally specifies the type of data being
accessed, such as sector or physical action
being performed, such as seek.
3:2
Function Code
1
This field specifies the type of access, and
varies by command. For example, this can
specify read, write, verify, etc.
X:4
Parameter1
Depends on command
Depends on command
Y:x+1
Parameter2
Depends on command
Depends on command
…
…
…
…
Total Words
256
Table 47 Key Sector Format
The action codes are defined in Table below.
Action Code
Block Data
TF Data
Description
0000h
-
-
Reserved
0001h
Read/Write
Y
Long Sector Access (Not Supported)
0002h
Write
N
SCT Write Same
0003h
-
Y
Error Recovery Control
0004h
-
Y
Features Control
0005h
Read
N
SCT Data Table
0006h-BFFFh
-
-
Reserved
C000h-FFFFh
-
-
Vendor Specific
Table 48 SCT Action Code List