-DS1
-Drive Select 1. Drive select bit for device 1, active low. D S 1 = 0 when device 1
(slave) is selected and active.
-DS0
-Drive Select 0. Drive select bit for device 0, active low. D S 0 = 0 when device 0
(master) is selected and active.
9.8 Device/Head Register
7
1
Figure 41. 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.
(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
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 com-
pletion, these bits are updated to reflect the current LBA bits 24-27.
9.9 Error Register
7
C R C
Figure 42. Error Register
This register contains status from the last command executed by the device, or a diagnostic code.
At the completion of any command except Execute Device Diagnostic, the contents of this register are valid
always even if E R R = 0 in the Status Register.
Following a power on, a reset, or completion of an Execute Device Diagnostic command, this register con-
tains a diagnostic code. See Figure 46 on page 69 for the definition.
64
O E M Specifications of DYLA-2xxxx 2.5 inch H D D
D e v i c e / H e a d R e g i s t e r
6
5
4
L
1
D R V
H S 3
When D R V = 0 , device 0 (master) is selected. When D R V = 1 , device 1
E r r o r R e g i s t e r
6
5
4
U N C
0
I D N F
3
2
1
0
H S 2
H S 1
H S 0
3
2
1
0
0
A B R T T K 0 N F
A M N F