Table 24 Drive Address Register - Hitachi HDS723020BLA642 Specifications

8.6 Drive Address Register
7
HIZ

Table 24 Drive Address Register

This register contains the inverted drive select and head select addresses of the currently selected drive.
Bit Definitions
HIZ
-WTG
-H3,-H2,-H1,-H0
-DS1
-DS0
Drive Address Register
6 5 4
-WTG -H3 -H2
High Impedance. This bit is not driven and will always be in a high impedance state.
-Write Gate. This bit is 0 when writing to the disk device is in progress.
-Head Select. These four bits are the one's complement of the binary coded address
of the currently selected head. -H0 is the least significant.
-Drive Select 1. Drive select bit for device 1, active low. DS1=0 when device 1 (slave)
is selected and active.
-Drive Select 0. Drive Select bit for device 0, active low. DS0=0 when device 0
(master) is selected and active.
Hitachi hard disk drive specifications
3 2
-H1 -H0
51
1 0
-DS1 -DS0