
Before Programming
1
2
3
4
5
6
7
App
Index
5-1
IM WT3001E-17EN
5.1 Messages
Messages and Queries
Messages are used to exchange information between
the controller and the instrument. Messages sent from
the controller to this instrument are called program
messages. Program messages that request a response
to be sent from this instrument to the controller are
called queries. Messages that the controller receives
from this instrument are called response messages.
If a query is included in a program message, this
instrument sends a response message after receiving
the program message. A single response message
is always returned in response to a single program
message.
Program Messages
The program message format is shown below.
<PMT>
;
<Program message unit>
<Program Message Unit>
A program message consists of one or more program
message units; each unit corresponds to one
command. The instrument executes the received
commands in order.
Each program message unit is separated by a
semicolon (
;
).
For details regarding the format of the program
message unit, see the next section.
Example
Unit
Unit
:INPut:CFACtor 3;INDependent OFF<PMT>
<PMT>
PMT is a program message terminator. The following
three types are available.
• NL (New Line)
Same as LF (Line Feed). ASCII code “0AH.”
• ^END
The END message (EOI signal) as defined in the
IEEE488.1. (The data byte that is sent with the END
message is the last data of the program message.)
• NL^END
NL with an END message attached. (NL is not
included in the program message.)
Program Message Unit Format
The program message unit format is shown below.
,
<Program header>
<Program data>
Space
<Program Header>
The program header indicates the command type. For
details, see page 5-3.
<Program Data>
If certain conditions are required in executing a
command, program data is added. A space (ASCII
code “20H”) separates the program data from the
header. If there are multiple sets of program data, they
are separated by commas (
,
).
For details, see page 5-6.
Example
:INPut:CFACtor 3<PMT>
Header
Data
Response Message
The response message format is shown below.
<RMT>
;
<Response message unit>
<Response Message Unit>
A response message consists of one or more
response message units; each response message unit
corresponds to one response.
Response message units are separated by a
semicolon (
;
).
For details regarding the format of the response
message unit, see the next section.
Example
Unit
Unit
:INPUT:CFACTOR 3;INDEPENDENT 0<RMT>
<RMT>
A response message terminator. It is NL^END.
Chapter 5
Before Programming