MSG between CLX and SLC via Backplane of second CLX

Anyone know if I can msg between a ControlLogix L71 (A) and an SLC5/05 (C) via backplane of second ControlLogix L71 (B)? ControlLogix (A) and SLC (C) are on different networks and the the second ControlLogix (B) has two ENBT's that links the 2 networks. See picture attached. I can write logic in ControlLogix (B) to exchange data between (A) and (C) but preferred to go direct.

Yes, you can.

The CIP Path is the key. You can read up on it in the user manuals, the Knowledgebase, or this site, but the basic idea is that the CIP Path consists of pairs of values: "Port, Address", separated by commas.

In this case, the CIP Path will be:

1, 2, 2, 192.168.1.2, 1, 3, 2, 192.168.10.3

Ken Roach said:

Yes, you can.

The CIP Path is the key

Click to expand...

I cannot understand why this very simple addressing concept is so misunderstood. Yet it causes so much problems.

Put simply, a "Path" is specified as ....

Port, Destination, [Port, Destination] ....


... repeat until you land at the target.

A "path" will always need at least two, and an even number, of parameters, otherwise the "port, destination" specification falls short.

However, when specifying paths the programming software will always replace path specifications it "knows about", if that path (or part of) is included in the I/O configuration of the project.

This will occur if you have had to add remote controllers to the I/O configuration for produced/consumed tag exchange.

It doesn't stop you entering the path explicitly, but what you will see (after entering the path) will be different.

daba said:

I cannot understand why this very simple addressing concept is so misunderstood. Yet it causes so much problems. ...

Click to expand...

Port,Destination[,Port,Destination]? Yeah, it seems simple, but when I look at the #2 here, I see


While I agree it is simple, it is only so "once you know the secret" - actually many many many secrets e.g. how does someone know that Ethernet is Port 2? Or how slots are numbered? Or when the Port is actually a Backplane? Or how do I learn that Backplane is 1?


So yeah, to the cognoscenti it is simple, but they have the decoder ring.

You can also go online with processors through deep CIP paths.