Echelon LNS DDE Server - Manual (Page 96)

Msg_code Optional. Specifies monitoring of responses with the given
message code, in decimal. If a message code is specified,
then the data returned by the LNS DDE Server does not
contain the code. If a message code is not specified, then the
first byte of the data returned by the LNS DDE Server
contains the received response code.
Parameters Optional.
The parameter options are:
-n bool
Specifies whether the client will receive message response
items from the LNS DDE Server even if the data has not
changed from the last time this response was received from
the network. May be set to True or False. If False, data is
reported to the client only if it has changed. If True, a byte
containing an incrementing counter will be appended to each
incoming response. If not specified, the default value
specified in the Messaging Options configuration dialog is
used.
This option may not work as expected for a series of
messages when some messages use ―nTrue and some use
―nFalse. It is recommended that you standardize on either
using this option or not then set it globally using the
Include Sequence Number option in the Network
Configuration Settings dialog.
-t type_name Specifies a format name to use for formatting the response.
For response messages, the LNS DDE Server does not
automatically determine the format. The format name can be
one of the five built-in formats (INTEGER, DISCRETE, REAL,
STRING, or RAW), a format name from the standard resource
file, or a format name from any user resource file. If the
format name is RAW, data will be returned in raw format.
When changing the data format using this parameter, the
change is applied to the entire data value. This may cause
unexpected results. For example, when reading a network
variable which is a floating point value, and changing the
format to an integer (-t INTEGER), the formatted value will
be an integer interpretation of the entire floating point
number, not just the integer part. The same thing applies
when changing the data type to floating point (-t REAL) for
an integer value. Make sure formats are compatible with the
network variable value.
Note:
Floating point values must be between –3.4E38 and
+3.4E38.
See Example 2 in Requesting a One-Time Update later in this chapter for an example
of a request using this specification.
7-4 Receiving and Sending Application Messages