AnyBus adapter and ControlLogix (data mis-alignment)

We have installed several of these AnyBus X-gateway adapters to allow us to communicate between ELAU and ControlLogix. All but one of them is up and functioning properly. We are reading 10 INTs out of each and on this one particular machine, the values don't match. The AnyBus has a web-server that you can view the data, and the value in the ELAU and AnyBus match (value of 6099), but in the ControlLogix, it shows up as -11497. The remaining words are all zeroes currently, but if they force word 1 to a "1", it shows up as 256. Same with word 2. This tells me that the data is off by 8 bits somehow. We are using the ETHERNET-GENERIC modules, but I also tried explicit messaging and get the same value(s). AnyBus pretty much said "good luck" and it wasn't anything on their end. I'm inclined to agree since the AnyBus web-server shows the correct value. We also swapped adapters with another machine, and the problem stayed with the machine, which I don't understand either.

The issue sounds like a big / little endian problem.
Use a SWPB instruction in the Contrologix to change the order of the bytes coming from / going to the gateway.

Mike_RH said:

The issue sounds like a big / little endian problem.
Use a SWPB instruction in the Contrologix to change the order of the bytes coming from / going to the gateway.

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I posted on here as a last ditch effort, and YOU SOLVED IT!
I have no idea why this one is ordered differently from the rest, but it worked. Thank you so much.

Actually...the Anybus should be able to be configured to take care of this...

NetNathan said:

Actually...the Anybus should be able to be configured to take care of this...

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Your correct. Someone else had this issue and talked to Anybus and had to change something in there setup. I had no luck with the factory years ago and ended up swapping bytes myself.

I have had issues with Anybus TS also at times.
There is a girl that works there that is very good and very helpful.
She actually worked with me over a 2 day period doing programming on an RS232 to Ethernet IP conversion problem.
I told here what I wanted it to do and what it was doing and she sent me configurations to test. We also encountered the byte swap issue.

That's good to know in case I encounter one of these again.
For now, we are just using the SWPB instruction (Thanks, Mike) on this one system. We didn't have the luxury of time to wait for the vendor to figure out where the Elau PLC code was mismatched.