Table 91: Command Data Structure - Hitachi HTS421212H9AT00 - Travelstar 120 GB Hard Drive Specifications

Command data structure: Data format of each command data structure is shown below.

Table 91: Command data structure

Description
Device Control register
Features register (7:0) (see Note)
Features register (15:8)
Sector count register (7:0)
Sector count register (15:8)
Sector number register (7:0)
Sector number register (15:8)
Cylinder Low register (7:0)
Cylinder Low register (15:8)
Cylinder High register (7:0)
Cylinder High register (15:8)
Device/Head register
Command register
Reserved
Timestamp (milliseconds from Power-on)
Note bits (7:0) refer to the most recently written contents of the register. Bits (15:8) refer to the contents of the reg-
ister prior to the most recent write to the register.
Travelstar 4K120 Hard Disk Drive Specification
134
Bytes Offset
1
1
1
1
1
1
1
1
1
1
1
1
1
1
4
18
00h
01h
02h
03h
04h
05h
06h
07h
08h
09h
0Ah
0Bh
0Ch
0Dh
0Eh