K6610170
Rev.2
Dec 22, 2004
- 31 -
7.0 Logical Interface
7.1. I/O Registers
Communication between the host system and the device is done through I/O registers. The Command
Block Registers are used for sending commands to the device or posting device status. The Control
Block Registers are used for controlling the device or posting device status.
Table 7.1 Register List
Addresses Functions
CS0- CS1- DA2 DA1 DA0 READ(DIOR-) WRITE(DIOW-)
Command Block Registers
0 1 0 0 0
Data
Data
0 1 0 0 1
Error
Features
0 1 0 1 0
Sector
Count Sector
Count
0 1 0 1 1
LBA
Low
(Sector Number)
LBA Low
(Sector Number)
0 1 1 0 0
LBA
Mid
(Cylinder Low)
LBA Mid
(Cylinder Low)
0 1 1 0 1
LBA
High
(Cylinder High)
LBA High
(Cylinder High)
0 1 1 1 0
Device/Head Device/Head
0 1 1 1 1
Status
Command
Control Block Registers
1 0 1 1 0
Alt.
Status
Device
Control
Invalid or Not Used
0 0
×
×
×
Invalid address
0 1
×
×
×
Data bus high impedance (not used)
1 0 0
×
×
Data bus high impedance (not used)
1 0 1 0
×
Data bus high impedance (not used)
'0' is low signal level. '1' is high signal level.
7.1.1. Data register
A 16-bit register to be used for transferring data blocks between the HDD's data buffer and the host.
