Message tags – Echelon Neuron C User Manual
Page 134
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How Devices Communicate Using Application Messages
the message does not need to be authenticated. The default is FALSE
(that is, not authenticated).
service
Specifies one of the following:
ACKD
(the default) - acknowledged service with retries
REQUEST – request/response protocol
UNACKD - unacknowledged service
UNACKD_RPT - repeated service (message sent multiple times)
Note: Do
not
use unackd or unackd_rpt in combination with
authenticated messages. Use only the ACKD or REQUEST service
type.
dest_addr An optional field in msg_out that explicitly specifies a destination
address. If dest_addr is not set, then the message is sent to the
implicit address associated with the tag, if the tag is bound. See
on page 130 for more information.
Note: To use this field, you must include the
Message Tags
A
message tag
is a connection point for application messages. Incoming
application messages are always received on a common message tag called
msg_in, but you must declare one or more message tags if
outgoing
explicit
messages are used. The incoming tag and each outgoing tag or tags can be
assigned a unique network address by a network tool.
A message tag declaration can optionally include connection information. The
syntax for declaring a message tag is as follows:
msg_tag [
connection
-
info
]
tag
-
identifier
[,
tag
-
identifier
...];
The
connection-info
field is an optional specification for connection options, in the
following form:
bind_info
(
options
)
The following connection options apply to message tags:
nonbind
Denotes a message tag that carries no implicit addressing
information and does not consume an address table entry. It is used
as a destination tag when creating explicitly addressed messages.
rate_est (
const-expr
) The estimated sustained message rate, in tenths of
messages per second, that the associated message tag is expected to
transmit. The allowable value range is from 0 to 18780 (0 to 1878.0
messages/second).
max_rate_est (
const-expr
) The estimated maximum message rate, in tenths of
messages per second, that the associated message tag is expected to
transmit. The allowable value range is from 0 to 18780 (0 to 1878.0
messages/second).
tag-identifier
A Neuron C identifier for the message tag.