[Logix] AOI, UDT, and how to manage inputs/outputs

[defcon.klaxon]

Oh man, have I painted myself into a corner here. I'll try to keep this as succinct as possible.

As many of you likely remember, I have a system of remote CompactLogix PLCs sending MSGs to "master" ControlLogix PLCs. I'll focus on one link: the remote Lake Pump Station (LPS) and the Filter Control Panel (FCP).

LPS has two pumps; I've created AOIs for Number of Starts (NOS) and Elapsed Time Meters (ETM).

FCP has multiple pumps; it uses the same AOIs for NOS and ETM.

I have UDTs set up for the pumps; they include the NOS and ETM AOIs.

Here's the problem: I pack the LPS data for NOS and ETM into DINT and REAL arrays and use the MSG to send it to FCP. Then I unpack the info into the pump tags at FCP. But the NOS and ETM tags are outputs, so copying the value into the LPS pump tag at FCP doesn't work.

I'm not sure what the work-around for this would be. I could create additional tags in the UDTs, and copy the NOS and ETM values into them, and then send those. That's a fair bit of tedious additional work though, and I'd hate to do all of that if there's an easier way to go about this.

Let me know if my description of the problem makes any sense. If there's any efficient way to tackle this, I'd love to hear what you guys think.

Thanks!

 

[defcon.klaxon]

Update: even the FCP AOI tags aren't working as expected; when I link to them in Wonderware, I don't see the value. This may be a bigger problem than I originally anticipated.

EDIT: this was because the AOI tags were set to no external access (didn't notice the scroll bar in the parameters area that lets you get over to where that is set up). So I got that figured out at least.