11 read command, Read command – FUJITSU M3097G User Manual

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4.4.11 READ command

The following table shows the normal sequence of the READ command when used
with this scanner.

Step

Bus phase

Initiator operation

¨ Æ

Target operation

1

BUS FREE

Verifies bus free

2

ARBITRATION

Obtains bus>usage
right

3

SELECTION

Selects target

Æ

Drives BSY signal

4

MESSAGE OUT

Selects logical unit

Æ

5

COMMAND

Specifies READ
(CDB)

Æ

Reads document

6

DATA IN

¨

Transfers image data

7

STATUS

¨

Reports GOOD status

8

MESSAGE IN

¨

Reports message (Command
Complete)

Releases BSY signal

9

BUS FREE

(1)

READ command: COMMAND phase (initiator Æ target)

The READ command is used by an initiator to request a target for transfer of data.
Upon receiving this command, the target returns scan data to the initiator.

The CDB of this command is shown in the following illustration.

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