Using Dde/Opc And Unscheduled Messages; Dde/Opc; Sending Unscheduled Messages - ProSoft Technology AN-X4-AB-DHRIO User Manual

Using DDE/OPC and Unscheduled Messages

DDE/OPC

You can use a DDE or OPC server, such as RSLinx, to access data using the AN-X4-AB-DHRIO
(DH+).
From the Ethernet side, the AN-X4-AB-DHRIO (DH+) looks like a 4-slot ControlLogix rack
with a 1756-ENET module in slot 0 and a 1756-DHRIO in slot 1.
Configure the AN-X module as you would a ControlLogix rack with a 1756-ENET Ethernet
module and 1756-DHRIO Data Highway Plus module.
Example: RSLinx
To configure a topic in RSLinx to access data using the AN-X4-AB-DHRIO (DH+):
1. Create a new topic. From the main menu select DDE/OPC/Topic Configuration. Click New
and give the topic a name.
2. For the Data source, browse the path to the destination device and click Apply.
3. On the Data Collection tab, check that the Processor Type is set to the correct type. 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 DDE or OPC client capable of communicating
with RSLinx.

Sending Unscheduled Messages

You can send messages from devices such as a ControlLogix to destinations on Data Highway
Plus using MSG instructions. For example, you can send messages to read or write data on a
PLC-5 or SLC 5/04.
To initiate messages from the Data Highway Plus side, refer to page 30.
Example: Sending Messages to a PLC-5
In this example, a ControlLogix is using the AN-X to send PLC-5 Typed Read commands that
read 100 integers from file N7:0 in a PLC-5 at address 77 octal on Data Highway Plus.
1. Add an AN-X to the Ethernet associated with the local 1756-ENBT or equivalent module, as
a 1756-ENET/A. Give it a Name and set the IP address to the address of the AN-X.
AN-X4-AB-DHRIO (DH+)
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