4.4.8SET SUBWINDOW command

The following table shows the normal sequence of the SET SUBWINDOW 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 SET

Æ

Sets subwindow

 

 

SUBWINDOW

 

 

 

 

(CDB)

 

 

 

 

 

 

 

6

DATA OUT

Specifies

Æ

 

 

 

subwindow data

 

 

 

 

 

 

 

7

STATUS

 

¨

Reports GOOD status

 

 

 

 

 

8

MESSAGE IN

 

¨

Reports message

 

 

 

 

(Command Complete)

 

 

 

 

 

 

 

 

 

Releases BSY signal

 

 

 

 

 

9

BUS FREE

 

 

 

 

 

 

 

 

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