Samsung 3.5" hard disk drives Benutzerhandbuch
DISK DRIVE OPERATION
SpinPoint V40 Product Manual
48
6.3.2 I/O Register - Address
Communication to or from the drive is through an I/O register that routes the input or output data to or from
registers addressed by a code on signals from the host (CS1FX-, CS3FX-, DA2, DA1, DA0, DIOR- and
DIOW-).
The Command Block registers are used for sending commands to the drive or posting status from the drive.
The Control Block registers are used for drive control and to post-alternate status. Table 6-3 lists these
registers and the addresses that select them.
Table 6-3 I/O Port Function/Selection Address
Address
Functions
CS1FX- CS3FX- DA2 DA1
DA0
READ(DIOR-) WRITE(DIOW-)
Control Block Registers
N
N
X
X
X
High Impedance
Not Used
N
A
0
X
X
High Impedance
Not Used
N
A
1
0
X
High Impedance
Not Used
N
A
1
1
0
Alternate Status
Device Control
N
A
1
1
1
Device Address
Not Used
Command Block Registers
A N 0
0
0
Data
Data
A N 0
0
1
Error
Register
Features
A
N
0
1
0
Sector Count
Sector Count
A
N
0
1
1
Sector Number
Sector Number
A
N
0
1
1
* LBA bits 0-7
* LBA bits 0-7
A
N
1
0
0
Cylinder Low
Cylinder Low
A
N
1
0
0
* LBA bits 8-15
* LBA bits 8-15
A
N
1
0
1
Cylinder High
Cylinder High
A
N
1
0
1
* LBA bits 16-23
* LBA bits 16-23
A N 1
1
0
Drive/Head Drive/Head
A
N
1
1
0
* LBA bits 24-27
* LBA bits 24-27
A N 1
1
1
Status
Command
N
N
X
X
X
Invalid Address
Invalid Address
* Mapping of registers in LBA mode.
Logic conventions are:
Logic conventions are:
A = signal asserted
N = signal negated
X = don't care
N = signal negated
X = don't care