IBM IC25N020ATDA04 - Travelstar 20 GB Hard Drive - Device;Head Register; Figure 56. Device;Head Register

10.7 Device/Head Register
HS0HS1HS2HS3DRV1L1
01234567
Device/Head Register
Figure 56. Device/Head Register
This register contains the device and head numbers.
Bit Definitions
Head Select. These four bits indicate the binary encoded address of the head. Bi
t
HS0 is the least significant bit. At command completion, these bits are updated to
reflect the currently selected head. The head number may be from zero to the
number of heads minus one. In LBA mode, HS3 through HS0 contain bits 24–27
of the LBA. At command completion, these bits are updated to reflect the current
LBA bits 24–27.
HS3,HS2,HS1,HS0
Device. When DRV = 0, device 0 (master) is selected. When DRV = 1, device 1
(Slave) is selected.
DRV
Binary encoded address mode select. When L = 0 , addressing is by CHS mode.
W
hen L = 1, addressing is by LBA mode.
L
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
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