The NI Industrial Automation Servers CD has an Allen Bradley (RSLinx) driver that can communicate with RSLinx through a dynamic link library (DLL). With the release of Industrial Automation Server CD 1.1, this server became an OPC server. Any OPC client, such as Lookout, BridgeVIEW, or other packages on the market, can connect to this server. Rockwell Automation developed their own OPC Server in version 2.0 of RSLinx. This version has been upgraded to version 2.20.
Rockwell Automation RSLinx 2.10 is an OPC server, meaning that any OPC Client should be able to exchange data with this server. The OPC server is available only with the OEM version or the full version, so the lite version of RSLinx does not have the OPC Server included. RSLinx OPC server is an in-process type of server, which means that you have to load a DLL to communicate with it. RSLinx 2.0 to 2.20 OPC servers only support the browsing capability on Control Logix 5000 series PLCs. Other Allen Bradley PLCs can be used on the OPC server by manually adding the addresses to be seen.
Another mechanism of communication between applications and RSLinx is through the DDE server that comes with RSLinx. The DDE server is only available for Rockwell Automation DDE clients in the OEM version. The drawback of DDE connection is that it is slower than OPC. If you decide to use the LabVIEW DDE VIs, then you need to have the full version of RSLinx.
This document was created using RSLinx 2.20.01.107.01, Allen Bradley MicroLogix 1500 PLC, ServerExplorer 2.4.1, Lookout 4.5 and the LabVIEW DSC module 6.0.2.. The cable model number used was 1761-CBL-PM02.