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4 ata c, Ommands, 1 ata command flow – SimpleTech Zeus Ultra User Manual

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ATA Commands

Functional Description

Zeus Ultra DMA Solid State Drives

21

2.4

ATA C

OMMANDS

This section provides information on the ATA commands supported on the Zeus SSD.
The commands are issued to the ATA by loading the required registers in the command
block with the supplied parameter, and then writing the command code to the register.

2.4.1

ATA Command Flow

1 Write the necessary parameter to the related Task File registers and by writing the

command in the Command register, the command is issued.

2 Upon the receipt of the command, the device sets the BSY bit within 400 n/sec.

3 If a data transfer command (e.g., Read command, Write command) was called, the

DRQ bit in the Status register will come up, indication that the transfer can begin.

Table 6.

ATA (IDE) Bus Addressing Modes

#CS0

#CS1

DA2

DA1

DA0

#IORD = “0”

#IOWR - “0”

1

1

X

X

X

Hi-Z

Not Used

1

0

0

X

X

Hi-Z

Not Used

1

0

1

0

X

Hi-Z

Not Used

0

0

X

X

X

Invalid

Invalid

1

0

1

1

0

Alternate status

Device Control

1

0

1

1

1

Device address

Not Used

0

1

0

0

0

Data

Data

0

1

0

0

1

Error

Feature

0

1

0

1

0

Sector Count

Sector Count

0

1

0

1

1

Sector Number

Sector Number

0

1

1

0

0

Cylinder Low

Cylinder Low

0

1

1

0

1

Cylinder High

Cylinder High

0

1

1

1

0

Drive/Head

Drive/Head

0

1

1

1

1

Status

Command