Device/Head Register; Error Register; Figure 70. Device/Head Register; Figure 71. Error Register - IBM DTLA-305040 - Deskstar 41.1 GB Hard Drive Specifications

-
-H3,-H2,-H1,-H0
-Head Select. These four bits are the 1's complement of the binary coded address of the
currently selected head. -H0 is the least significant.
-DS1 -Drive Select 1. Drive select bit for device 1, active low. DS1=0 when device 1 (slave) is
selected and active.
-DS0 -Drive Select 0. Drive select bit for device 0, active low. DS0=0 when device 0 (master) is
selected and active.

9.8 Device/Head Register

Figure 70. Device/Head Register

This register contains the device and head numbers.
Bit Definitions
L Binary encoded address mode select. When L=0, addressing is by CHS mode. When
L=1, addressing is by LBA mode.
DRV Device. When DRV=0, device 0 (master) is selected. When DRV=1, device 1 (slave) is
selected.
HS3,HS2,HS1,HS0
Head Select. These four bits indicate binary encoded address of the head. HS0 is the
least significant bit. At command completion these bits are updated to reflect the cur-
rently 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.

9.9 Error Register

Figure 71. Error Register

This register contains status from the last command executed by the device or a diagnostic code.
Device/Head Register
7 6 5
1 L 1
Error Register
7 6 5
ICRCE UNC 0
Deskstar 40GV & 75GXP hard disk drive specifications
4 3 2
DRV HS3 HS2
4 3 2
IDNF 0 ABRT TK0NF
72
1 0
HS1 HS0
1 0
AMNF