topic Success in NI Labs

Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Mon, 15 Sep 2008 17:19:26 GMT

Welcome to the NI Labs EtherNet/IP Industrial Protocol Support project. This thread is intended to foster discussion about the project, so please post your questions, comments, suggestions and bug reports and I'll be happy to respond.

This library allows direct communication between NI systems running LabVIEW and various PLCs using the EtherNet/IP industrial communications protocol. The current version supports explicit messaging communication to read or write data stored in named tags on the PLC. PLCs that support this mechanism include Allen-Bradley's ControlLogix and CompactLogix series. There are a number of native data types supported including boolean, numeric and string types.

The library can be used in LabVIEW 8.2 and up on both Windows systems as well as systems running LabVIEW RT. To use the library on an RT target you must first install the library onto the target under the Add/Remove Software tree item in MAX.

One of the goals of this release on NI Labs is to get a better idea of what features are in most demand to add support for. We'd love to get feedback regarding need for additional data types, additional PLC addressing support, Implicit I/O communication, etc.

Eric G

National Instruments

Message Edited by Support on 09-15-2008 12:19 PM

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

dwisti — Thu, 25 Sep 2008 17:57:08 GMT

I really appreciate NI for working on industrial protocols. It is very helpful for us in the control industry. That said, lets get into the suggestions and comments.

- It would be nice to see a native Labview version of EthernetIP, unlocked of course. Like this over on LAVA. Or maybe release the source code for ethernetIPInterface.dll. NI need to eat its own dog food here.

- Add support for IO connections or Unconnected PCCC read and write messages.

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Fri, 26 Sep 2008 14:43:40 GMT

Hi dwisti,

Thanks for the feedback. I can tell you we are looking at future support of I/O connections (implicit messaging) capability as well as the PCCC support, but we'd like to hear back from customers regarding the need for such features. Aside from the PCCC support to allow compatibility to older PLCs, what types of use cases would the I/O connections make easier?

While I can't explain here all the reasons for why our implementation is not 100% in LabVIEW code, I will say there are some advantages to the current approach including future usage by our CVI customers as well.

Please keep the comments and suggestions flowing,

Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

dwisti — Mon, 29 Sep 2008 03:53:39 GMT

Eric,

PCCC is not only older PLCs. Some of the new Micrologix PLCs only support PCCC. I have a need for I/O connections with a 3rd party device (i.e. not Rockwell) that only has support for I/O connections. It does not support Explicit Messages. Whats CVI? Just kidding... but your telling me text based code has advantages over G? We don't use CVI but I can see why your implementation is not Labview. Its a shame not to code this in 100% Labview. Those CVI programmers don't need EIP anyway. Just code it in Labview and compile a DLL for CVI.

David

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

simroc76 — Mon, 13 Oct 2008 15:07:59 GMT

How can I open a new session?

I seen that the dll used has others "Functions" (like LV_OpenSession) but only the reading and writing ones are shown.

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Mon, 13 Oct 2008 15:28:52 GMT

Hi Simroc,

The sessions are opened on demand by LabVIEW (and closed by it as well when they are deemed to no longer be needed). You should not need to open/close the sessions manually, just leave it unwired. Explicit open/close VIs may be added to the palette eventually but their only usefulness for explicit messaging would be for allowing you to cancel a blocking operation programatically.

Hope this helps,

Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

simroc76 — Fri, 07 Nov 2008 10:43:42 GMT

Hi Eric,

many thanks for the reply!

Now I'm able to read and write some tags in my Allen-Bradley PLC LOGIX 5343 but only using a code developed in LabVIEW 8.6...

If I use the same instructions in a code developed in LabVIEW 8.2, I receive the following error:

Error -251723770 occurred at EthernetIP Tag Read INT.vi;
Details: The session is invalid

Possible reason(s):
Ethernet/IP Industrial Protocol: (Hex 0xF0FF0006) The session is invalid

Do you have any idea about this behaviour?

We have to integrate this functionality in our code developed in LV 8.2 without move all the software to LV 8.6...

Thanks in advance,

Simone

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Fri, 07 Nov 2008 13:46:35 GMT

Hi Simone,

That is odd. Is it possible to try upgrading your 8.2 to 8.2.1? The two should have compatible behavior but I've only used 8.2.1. Another thing to confirm is checking whether there is a default string filled in on the session refnum wire. It should be there by default but you could try putting some name in manually.

Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

simroc76 — Fri, 07 Nov 2008 14:01:46 GMT

Hi Eric,

I have reinstalled the EtherNet/IP driver addon and now it works fine also with LV 8.2!

I don't know what happened before...

Thanks,

Simone

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

alberto-spalab — Wed, 12 Nov 2008 10:39:50 GMT

Hi, i'm not able to run correctly the "EthernetIp Read Tag.vi" and "EthernetIp WriteTag.vi"

I have always the error:

Error -251723760 occurred at EthernetIP Tag Read DINT.vi;
Details: CIP Error - Extended status may be available
CIP Extended Status: 0x311

If i use the llb that i downloaded from LAVA always run correctly....

Any suggest?

Alberto Sgarbi

Studio Progetti Automation s.r.l.

Italy

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Wed, 12 Nov 2008 17:32:21 GMT

Alberto,

My guess is your syntax of the PLC address is incorrect. The syntax is generally <PLC IP address>,<backplane port number>,<Logix slot number>. I looked up the CIP extended status code in RSLogix5000 and it maps to "Port not available" (note that these extended codes are device-specific, but most likely common across most Rockwell devices). If I change the address I am using from x.x.x.x,1,0 to x.x.x.x,8,0 I see the same 0x311 extended status code.

Can you describe your PLC configuration (type, slot layout) and what the address string you are using to address it is?

Thanks,
Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

mjo — Tue, 13 Jan 2009 22:28:29 GMT

Hi I have a similar issues to Alberto,...

Error -251723760 occurred at EthernetIP Tag Read DINT.vi;
Details: CIP Error - Extended status may be available
CIP Generic Status: 0x4
....

My Backplane is a 1756-A13

Slot zero: 1756-L64

Slot one: 1756-ENBT/A

Slot two Thru five: 1756-DNB

slot six: 1756-CNB/E

slot seven: 1756-DHRIO

remaining slots unpopulated as yet.

Also can you elaborate on the tag structure, maybe its just me but the description in the help file leaves it a little too unclear as to how to build it up.ie, referencing a controller tag, compared to a task (program) tag etc. perhaps an example of an actual tag that you are referencing.

cheers

Martin.

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Tue, 13 Jan 2009 23:09:56 GMT

Martin,

The error 0x04 you are getting seems to mean an IOI syntax error on your tag name. This is different from an error addressing the PLC because it is the tag name that is incorrect rather than the address.

In general, the tag name is exactally what you see in RSLogix5000. Any controller tags you create show up in the "Controller Tags" spreadsheet. My understanding is that the only difference between program tags and controller tags is scope. Only controller tags can be accessed externally from the PLC though. If the datatype can be expanded then RSLogix shows you the sytax for accessing the sub-elements.

If I add a controller tag called "TestArray" that is a DINT[3] array type in RSLogix, I can access it the following ways:

-By "TestArray" - Gets/Set the array of 1-3 elements, depending on the count parameter

-By "TestArray[N]" (where N is an index) - Gets/Sets the array starting at offset N

-By "TestArray[N].0" - Gets/Sets an individual BOOL bit of the DINT at offset N

Hope this helps,

Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

mjo — Tue, 13 Jan 2009 23:52:24 GMT

Thanks Eric, Nail on the head stuff there.

It seems i can read and write at the controller level with no problems but i cant access program tags...

Cheers

Martin

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

Swobodatech — Mon, 19 Jan 2009 14:44:31 GMT

Hello,

I am having a problem writing information from my Vision Builder 3.6 application to my RSLogix5000. I have loaded the E/IP add-on to the Vision builder to write to tags but when I try to write to the tag it gives me an "invalid tag name". Even though loaded the tag names from an export file .l5k. These tags are also controller tags not program tags.

Adam

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Mon, 19 Jan 2009 16:29:19 GMT

Adam,

It would be helpful if you could attach screenshots showing your tags list in RSLogix as well as the EN/IP configuration screen in VBAI. It sounds like a configuration issue.

-Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

Swobodatech — Mon, 19 Jan 2009 17:07:15 GMT

Eric,

Here are the images that you wanted to see.

Adam

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Mon, 19 Jan 2009 17:15:59 GMT

Can you add a screenshot showing the tags in RSLogix?

-Eric

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

Swobodatech — Mon, 19 Jan 2009 18:07:48 GMT

Screen Shot of JPEG

Re: Welcome to EtherNet/IP Driver for Communication to Allen Bradley ControlLogix PLCs

BlueCheese — Mon, 19 Jan 2009 19:18:47 GMT

Adam,

It looks like you're using a different version of RSlogix than me (15.01), so I'm not sure what some of the checkboxes in the leftmost column are for. However, it does look like those tags should be accessible and their configuration appears to match how you have them configured in Vision Builder AI.

One thing I noticed that is likely an issue is that the network address is probably not correct. It should be more than just an IP address as the addressing needs to point to the CPU module hosting the tag. If you click the help button while in the step you should get a description of how that field should be populated:

In the Network Path control, enter the path to the target. The syntax for a simple system is <PLC address>,<backplane port number>,<Logix slot number>. For example, 10.0.0.1,1,0 is the routing path for a ControlLogix 5561 with IP address 10.0.0.1 and with the processor in slot 0 of an AB-1756 4-slot backplane.

In the next version of Vision Builder this step's inputs should be a little more clear.

Eric