ControlLogix MSG block .ERR and .ERR_SRC help?

Hello,

I'm doing Generic CIP MSG block to a Gefran SCR w/Ethernet/IP from a v20 L61 processor via an 1756-ENBT. My MSG block is throwing ERR = 0x0020 which is undefined in the help and reference manual, and ERR_SRC = 9. I had to dig into the manual to find out what ERR_SRC was again (can't remember everything) and this is what it says: "Used by RSLogix 5000 software to show the error path on the Message Configuration dialog box". So it would appear the dialog box should be showing me which parameter is causing the issue, but if it is I can't see it.

Anybody know how to decipher ERR_SRC? Or have any other suggestions?

Thanks,
-Brad

When troubleshooting CIP messaging, there's really no substitute for capturing the data on the wire.

Do you have a managed switch or another way to connect Wireshark so you can capture the data between the controller and the Gefran device ?

You might also try using another tool like RSNetworx for EtherNet/IP or the Molex messaging tool to send the message. The error code might be shown differently with those tools, and you could easily run Wireshark on the same PC to capture the data on the wire.

About the ERR_SRC element; that's made to tell you how far down the CIP Path the message made it before erroring.

Does this message go directly out of the Ethernet port of the 1756-ENBT, or is there some intermediate ControlNet or multiple Ethernet links involved ?

If it was the Gefran device that was giving a bad response, I would expect ERR_SRC to be 4: Backplane, ENBT Module, Ethernet Network, Gefran IP.

Thanks Ken. I have a huge 19" rack-mount Ethernet hub (yes, hub) I have kept just for Wiresharking. I can dig that out. I may give the Molex util a try first and see if that helps.

As for the path, yes, it's L61-Backplane-ENBT-Network-GFX4 (Gefran). I believe the Gefran does do all it's fieldbus comms by internally converting to Modbus calls, so perhaps there a few more steps internal to the Gefran increasing that count?

I'll update again here when I know more.

Thanks,
-Brad

Wow, I may need a manual for the Molex EIP Tool. I may opt for digging out the hub in the interest of time, this time...

Can you post the details of your MSG instruction ?

The Service, Class, Instance, Attribute and Path will tell us the CIP information, and the source or destination tag datatypes and Length will tell us how the ControlLogix intends to handle the message.

Detailed text or screenshots are welcome.

Ken,

Thanks for all your help. I figured out the Molex EIP Tool and it is very cool for debug with Wireshark.

I did figure out my issue. The Gefran SCRs have a pair of rotary switches for the Modbus slave address (you can run multiple SCRs off one SCR with the Ethernet/IP interface via Modbus). Out of the box these are likely set at 00 (ours was), and the valid address range is 01 to 99. Since I only have one SCR and no Modbus network, I just skimmed that section of the manual and didn't set that up. The serial port used for SCR configuration worked with address '01' so I thought I was good to go with the MSG block as the CIP Instance value is the Modbus slave address. As soon as I changed the rotary switches from 00 to 01 it started working.

Thanks again!