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1 reserve unit command – FUJITSU SCANPARTNER 600C User Manual

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4-19

(d) A bit and field described as "Reserved" are 0.

If this scanner receives a value other than 0, it returns an error as follows:
Status key: B'00001 '(CHECK CONDITON)
Sense key: X~5'(ILLEGAL REQUES~I)

The commands supported by this scanner are listed below.

Table 4-7

Commands

Command

Operation

code (hex)

Description

RESERVE UNIT

16

Declares the exclusive use of a logical unit

RELEASE UNIT

17

Cancels the declaration of the exclusive use of a logical unit

INQUIRY

12

Examines the information regarding the target and logical unit

REQUEST SENSE

03

Requests a target for sense data

SEND DIAGNOSTIC

ID

Requests a target for self-check

TEST UNIT READY

00

Checks whether or not a logical unit is ready

SET WINDOW

24

Sets a window

OBJECT POSITION

31

Controls the automatic document feeder

READ

28

Requests transfer of image data

SCAN

1B

Requests the target to begin a scan operation

4.4.1 RESERVE UNIT command

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

Table 4-8

RESERVE UNIT command

Step

Bus phase

Initiator operation

←→

Target operation

1

BUS FREE

Verifies bus free

2

ARBITRATION

Obtains bus-usage right

3

SELECTION

Selects target

Drives BSY signal

4

MESSAGE OUT

Selects logical unit

5

COMMAND

Specifies RESERVE UNIT (CDB)

6

STATUS

Reports GOOD status

7

MESSAGE IN

Reports message

(Command complete)

Releases ESY signal

8

BUS FREE