12.2 Execute Device Diagnostic (90h)
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
V
V
V
Figure 87. Execute Device Diagnostic Command (90h)
The Execute Device Diagnostic command performs the internal diagnostic tests implemented by the
device. The results of the test are stored in the Error Register.
The normal Error Register bit definitions do not apply to this command. Instead, the register contains a
diagnostic code. See Figure 71 on page 26 for the definition.
7 6 5 4 3 2 1 0
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
1 - 1 - - - - -
1 0 0 1 0 0 0 0
4
3
2
1
0
IDN
0
ABT
T0N
AMN
V
V
V
V
V
Deskstar 40GV & 75GXP hard disk drive specifications
Command Block Input
Registers
Register
Data
Error
Sector Count
Sector Number
Cylinder Low
Cylinder High
Device/Head
Status
Status Register
7
6
5
4
BSY
RDY
DF
DSC
0
V
0
–
110
7 6 5 4 3 2 1 0
- - - - - - - -
see below
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
see below
3
2
1
0
DRQ
COR
IDX
ERR
–
0
–
0