beautypg.com

EXFO FLS-2200 Broadband Source User Manual

Page 45

background image

Using Your Broadband Source in an Automated Test Environment

Broadband Source

37

Message Management

Output queue

Consists of a First-In, First-Out

(FIFO) data structure.

When the instrument acts as a

talker, it sends response messages

(from the output queue) to the

controller. Response messages all

end with a <RESPONSE MESSAGE
TERMINATOR>
, see the appendix

on data types.

Total storage capacity: only limited

to the device’s memory.

As soon as there is data in the

output queue, the Message

AVailable bit (bit number 4 –MAV

from the Status Byte register) is set

to 1.

Remains empty if no query is

received or if the query contains

an error.

The Output queue will be

cleared by:

Reading all the items it

contains.

Turning off the power.

Sending a Device Clear

(DCL) message to the

instrument.

Sending a

Selected Device Clear

(SDC) message to the

instrument.

Attempting to send a

command before

reading the responses to

previous queries (an

error will also be

raised).

Data structure

Characteristics

Clearing