EXFO IQS-600 Integrated Qualification System - Manual (Page 185)

Using IQS Products in an Automated Test Environment
Integrated Qualification System 177
Message Management

Except for the string and binary
block contents, the following
transformations are made on the
incoming data:
character conversion from lower
case to upper case.
conversion of “<wsp>”
characters to spaces.
conversion of multiple blanks to a
single blank.

Parser begins to process messages
when the <PROGRAM MESSAGE
TERMINATOR> is received or if
the input buffer is full.
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