Samsung spinpoint v40 manual 2 I/O Register Address, Control Block Registers, N N N A a a

DISK DRIVE OPERATION

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 6-3I/O Port Function/Selection Address

Address

Functions

CS1FX- CS3FX- DA2

DA1

DA0

READ(DIOR-)

WRITE(DIOW-)

Control Block Registers

N N N N N

N A A A A

X

0

1

1

1

X X 0 1 1

X X X 0 1

High Impedance

High Impedance

High Impedance

Alternate Status

Device Address

Not Used

Not Used

Not Used

Device Control

Not Used

Command Block Registers

A A A A A A A A A A A A N

N N N N N N N N N N N N N

0

0

0

0

0

1

1

1

1

1

1

1

X

0

0

1

1

1

0

0

0

0

1

1

1

X

0

1

0

1

1

0

0

1

1

0

0

1

X

Data

Error Register

Sector Count

Sector Number

*LBA bits 0-7 Cylinder Low

*LBA bits 8-15 Cylinder High

*LBA bits 16-23 Drive/Head

*LBA bits 24-27 Status

Invalid Address

Data

Features

Sector Count

Sector Number

*LBA bits 0-7 Cylinder Low

*LBA bits 8-15 Cylinder High

*LBA bits 16-23 Drive/Head

*LBA bits 24-27 Command Invalid Address

*Mapping of registers in LBA mode. Logic conventions are:

A = signal asserted N = signal negated X = don't care

48 SpinPoint V40 Product Manual