Message formats – Rockwell Automation 1395 ControlNet Communication Board User Manual

Page 25

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3–11

Configuration & PLC Interfacing

Publication 1395–5.37– March, 1999

PLC Typed Read (N30:0-999) - This request translates into a read
parameter full message in the Drive. Each parameter specified results in
13 words of data (actual value, minimum value, maximum value,
descriptor, and parameter text). You can read a maximum of 5 parameters
with this service.

PLC Typed Read (N40:0-39) - This message emulates the RIO block
transfer functions available on the CNA board with the exception of the
multiple parameter read. Refer to the message structure section of this
chapter for details on the available messages and their use.

NOTE: With this command there are no BT flags to synchronize the
Write/Read operation as on the RIO.

PLC Typed Write (N40:0-39) - This message emulates the RIO block
transfer functions available on the MCA board with the exception of the
multiple parameter write. Refer to the message structure section of this
chapter for details on the available messages and their use.

NOTE: With this command there are no BT flags to synchronize the
Write/Read operation as on the RIO.

PLC Typed Read
(N70:0-119)
for Trend 1
(N71:0-119) for Trend 2
(N72:0-119) for Trend 3
(N73:0-119) for Trend 4 - This message reads the trend sampled data,
which is the data retained when a trigger condition occurs. A file of 70
corresponds to Trend 1, 71 to Trend 2, 72 to Trend 3, and 73 to Trend 4.

Message Formats

This section of the manual provides a detailed explanation of the
messages that the Drive supports. These messages are used by
ControlNet to program Drive parameters, read parameter data, and control
other Drive functions.

The following table summarizes the valid function code that is displayed
in word 3 of the PLC message write header message. A complete
description of the messaging write header is provided on the specified
page.

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