YOKOGAWA wt1600, Руководство пользователя

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Before Programming
4-1
IM 760101-11E
4
4.1 Messages
Blocks of message data are transferred between the
controller and this instrument during communications.
Messages sent from the controller to this instrument
are called program messages, and messages sent
back from this instrument to the controller are called
response messages.
If a program message contains a message unit, i.e. a
command which requests a response, this instrument
returns a response message. A single response
message is always returned in reply to a program
message.
Program Messages
The format of a program message 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. This instrument executes commands one
by one according to the order in which they are
received.
Program message units are delimited by a “
;
”.
For a description of the format of the program
message unit, refer to the explanation given further
below.
Example
Unit Unit
:HARMonics:STATe ON;OBJect SIGMA<PMT>
<PMT>
PMT is a terminator used to terminate each program
message. The following three types of terminator are
available.
NL
(New Line) : Same as LF (Line Feed). ASCII code
“0AH” is used.
^END
: END message defined in IEEE488.1.
(EOI signal)
(The data byte sent with an END
message will be the final item of the
program message unit.)
NL^END : NL with an END message attached
(NL is not included in the program
message unit.)
Program message unit format
The format of a program message unit is shown below.
,
<Program header> <Program data> Space
<Program header>
A program header is used to indicate the command
type. For details, refer to page 4-3.
<Program data>
If certain conditions are required for the execution of a
command, program data must be added. Program
data must be separated from the header by a space
(ASCII code “20H”). If multiple items of program data
are included, they must be separated by a “ , ”
(comma). For details, refer to page 4-5.
Example
:HARMonics:STATe ON<PMT>
Header Data
Response Messages
The format of a response message is shown below.
<RMT>
;
<Response message unit>
<Response message units>
A response message consists of one or more
response message units: each response message unit
corresponds to one response.
Response message units are delimited by a “
;
”.
For the response message format, refer to the next
page.
Example
Unit Unit
:HARMONICS:STATE 1;OBJECT SIGMA<RMT>
<RMT>
RMT is the terminator used for every response
message. Only one type of response message is
available;
NL^END
.
Chapter 4 Before Programming