Western Digital Ultrastar DC HC310 - Table 125 Initialize Device Parameters Command (91 H)

152
Western Digital Hard Disk Drive OEM Specification
11.14 Initialize Device Parameters (91h)
Command Block Output Registers
Command Block Input Registers
Register
7
6
5
4
3
2
1
0
Register
7
6
5
4
3
2
1
0
Data
-
-
-
-
-
-
-
-
Data
-
-
-
-
-
-
-
-
Feature
-
-
-
-
-
-
-
-
Error
-
-
-
-
-
-
-
-
Sector Count
V
V
V
V
V
V
V
V
Sector Count
-
-
-
-
-
-
-
-
Sector Number
-
-
-
-
-
-
-
-
Sector Number
-
-
-
-
-
-
-
-
Cylinder Low
-
-
-
-
-
-
-
-
Cylinder Low
-
-
-
-
-
-
-
-
Cylinder High
-
-
-
-
-
-
-
-
Cylinder High
-
-
-
-
-
-
-
-
Device/Head
1
-
1
D
H
H
H
H
Device/Head
-
-
-
-
-
-
-
-
Command
1
0
0
1
0
0
0
1
Status
...See Below ...
Error Register
Status Register
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
CRC
UNC
0
IDN
0
ABT
T0N
AMN
BSY
RDY
DF
DSC
DRQ
COR
IDX
ERR
0
0
0
0
0
V
0
0
0
V
0
-
-
0
-
V
Table 125 Initialize Device Parameters Command (91h)
The Initialize Device Parameters command enables the host to set the number of sectors per track and the number
of heads minus 1, per cylinder. Words 54-58 in Identify Device Information reflect these parameters.
The parameters remain in effect until following events:
 Another Initialize Device Parameters command is received.
 The device is powered off.
 Soft reset occurs and the Set Feature option of CCh is set instead of 66h.
Output Parameters To The Device
Sector Count
The number of sectors per track. 0 does not mean there are 256 sectors per track, but there is no
sector per track.
H
The number of heads minus 1 per cylinder. The minimum is 0 and the maximum is 15.
Note:
The following conditions needs to be satisfied to avoid invalid number of cylinders beyond FFFFh.
(Total number of user addressable sectors)/((Sector Count)*(H+1)) = < FFFFh
The total number of user addressable sectors is described in Identify Device command.