Rockwell Automation 56AMXN/B ControlLogix AutoMax Comm Module - Manual (Page 53)

AutoMax DCSNet/RE RIO Module Page 53
Publication number 56AMXN-UM002A-EN-P November 2002
Using DDE/OPC to Access DCS Data on the Module
You can use a DDE or OPC server such as RSLinx, or any other HMI
capable of accessing the ControlLogix backplane, to access the DCS data
directly on the 56AMXN. The module “emulates” PLC-5 integer files
100-155. Each file corresponds to a DCS drop. For example, if you
create tags to access N102, N102:0 to N102:63 represent Drop 2’s DCS
registers.
The 56AMXN supports Word Range Read/Write, Typed Read/Write,
Read/Modify/Write, and PLC-3 Bit Write messages, with either logical
ASCII or logical binary addressing.
To configure a topic in RSLinx to access data on the 56AMXN:
1. Create a new topic. From the main menu select DDE/OPC/Topic
Configuration. Click New and give the topic a name.
2. Select the Data Source tab, browse the path to the 56AMXN module
and click Apply.
3. On the Data Collection tab, set the Processor Type to PLC-5. Check
Polled Messages and select an appropriate update rate. Leave
everything else unchecked. Click Apply
4. You do not need to set anything on the Advanced Communication
tab.
5. Click Done to complete the topic configuration.
You should now be able to access data using any client capable of
communicating with RSLinx.
If you write to a register that is also mapped to ControlLogix scheduled
data, the value you write will be overwritten when the next scheduled
data update occurs.