l.Sense>key specific bytes: Bytes F to 11 This field is reserved on this scanner. (X©00000000￿ must not be expected.)

4.4.5SEND DIAGNOSTIC command

The following table shows the normal sequence of the SEND DIAGNOSTIC 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 SEND

Æ

Performs self>test

 

 

DIAGNOSTIC

 

 

 

 

(CDB)

 

 

 

 

 

 

 

6

STATUS

 

¨

Reports GOOD status

 

 

 

 

 

7

MESSAGE IN

 

¨

Reports message (Command

 

 

 

 

Complete)

 

 

 

 

 

 

 

 

 

Releases BSY signal

 

 

 

 

 

8

BUS FREE

 

 

 

 

 

 

 

 

(1)SEND DIAGNOSTIC command: COMMAND phase (initiator Æ target)

The SEND DIAGNOSTIC command is used by an initiator to request a target or logical unit for self>test. Two types of self>diagnostic are: (a) the self>test performed by the unit itself, and (b) the test conducted according to the instruction data from the initiator.

This scanner supports the self>test only.

The results of self>test are reported using the status and sense data. The CDB of this command is shown in the following illustration.

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