Scanner Interface

A.4.5 SEND DIAGNOSTIC command

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

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 SEND

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 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.

Appendix A-46