Rockwell Automation 1734-8CFGDLX, Руководство пользователя

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Publication 1734-UM015A-EN-E - November 2009
58 Configuring POINT I/O and ArmorPOINT I/O DeviceLogix modules using RSNetworx for DeviceNet
If the POINT I/O DeviceLogix module is consuming data from a peer that
has double precision analog data (32-bit), like the 1734-VHSC24, the data can
be used in logic by addressing the high-word and low-word separately. By
using math functions (multiply and add), the two words can be combined into
one value.
See Very High Speed Counter Input Modules in Appendix A .
Produce Data Without
Using a Master
With the POINT I/O DeviceLogix module (and other DeviceLogix modules
that support "ZIP"), you can send data to another listener without a network
master to set up the connection.
The following parameters are used to configure this feature:
Soon after power-up and getting online, when Auto Produce is enabled, the
POINT I/O DeviceLogix module begins producing change-of-state (COS)
type I/O data on the connected network or backplane. It produces the
selected "Auto Produce Assembly" at the selected "Auto Produce EPR"
(Expected Packet Rate).
The Auto Produce Assembly data can be:
•
20 bytes of produced data (it sends all possible data)
•
8 bytes of produced data (this does not require the fragmentation
protocol, so it will reduce network bandwidth)
•
1 byte of produced data (only the state of the 8 I/O)
A description of these assemblies can be found in Chapter 4.
The Auto Produce EPR sets the cyclic rate at which data is produced if there is
no change of I/O state. If there is a change of state, new data is produced
immediately. If data changes often, to reduce change-of-state traffic on the
network, you can increase the Auto Produce Production Inhibit Time (PIT).
For example, if the PIT is set to 10 ms, the quickest the module can produce
data is once every 10 ms even if there is a change of state.
Auto Produce is only recommended on a DeviceNet network in situations
where a master is not required.
Parameter
number Parameter name Parameter
description Default value
74 Auto Produce See page 50 . Disabled
75 Auto Produce EPR See page 51 . 1000 ms
76 Auto Produce PIT See page 51 . 1 ms
99 Auto Produce
Assembly See page 51 . 20-byte produced
(default)