Initialize Device Parameters (91H); Figure 91. Initialize Device Parameters Command (91H) - IBM IC25N020ATDA04 - Travelstar 20 GB Hard Drive Specifications

13.12 Initialize Device Parameters (91h)

Command Block Output Registers
Register
Data
Feature
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Command
Error Register
7 6 5
CRC UNC 0
0 0 0

Figure 91. 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 reflects these
parameters.
The parameters remain in effect until the following events occur:
! Another Initialize Device Parameters command is received.
! The device is powered off.
! A hard reset occurs.
! A soft reset occurs and the Set Feature option of CCh is set instead of 66h.
Output Parameters To The Device
Sector Count
H
7 6 5 4 3 2 1 0
- - - - - - - -
- - - - - - - -
V V V V V V V V
- - - - - - - -
- - - - - - - -
- - - - - - - -
1 - 1 D H H H H
1 0 0 1 0 0 0 1
4 3 2 1
IDN 0 ABT T0N AMN
0 0 V 0
This indicates the number of sectors per track. Zero (0) indicates that there are
no sectors per track.
This indicates the number of heads minus 1 per cylinder. The minimum is 0 and
the maximum is 15.
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
Command Block Input Registers
Register
Data
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status
Status Register
0 7 6 5
BSY RDY DF
0 0 0 0
137
7 6 5 4 3 2 1 0
- - - - - - - -
See Below
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
See below
4 3 2 1 0
DSC DRQ COR IDX ERR
- - 0 - V