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AB ControlLogix MSG Instruction/Gateway Question...

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ponycar17

Electrical
Jun 15, 2004
22
Ok, so I've been through Rockwell Technical Support [yinyang] with only minor injuries, and still don't have the answer to this burning question...

I am attempting to send a message over several networks, through two gateways, and on to an RSSQL server, but I still haven't received a satisfactory response as to whether any method will work, and if so, how to do it...

I am starting the message on a FlexLogix processor via ControlNet, and then crossing one ControlLogix gateway, which houses a ControlNet module, a DHRIO module, and an Ethernet module. Communications over this gateway have been performed successfully to DH+ and to ENet with CNET as a starting point. My MSG instruction needs to go over this gateway to another DH+ gateway, and then over that gateway's backplane, and on to an Ethernet card, which will address a RSSQL server that is looking for 10 type Int words from my FlexLogix processor... We have successfully written to the FlexLogix processor from RSSQL, but not from the processor to the server.

The major issue...

I'm hopping from ControlNet to DH+, then from DH+ in another gateway, over to Ethernet, and onto an RSSQL server. Is this even possible? Can DH+ handle the routing if I use a complete message MSG instruction path from the CNET all the way to the ENET destination PC? Do I need to use routing tables in the gateways? Which instruction type (CIP, DH+, or CIP with source ID), should I use?

As you can see, I have a lot of questions. I've tried variants of all the different message types, and I've even tried using a routing table in both gateways. Right now, I'm just looking for advice...

Thanks in advance!

I'm all [bigears]!
 
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Let me make sure I understand the routing

Flexlogix Processor --> Controlnet --> 1756-CNB --> backplane --> 1756-DHRIO--> DH+ -->1756-DHRIO --> backplane -->1756-ENBT --> RsSQL Server

Is this correct?

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TW Controls -
 
My advise is to break it down into 3 messages

1st CIP from flex processor to processor that controls DHRIO card, copy this to a buffer file
Flexlogix Processor --> Controlnet --> 1756-CNB --> backplane -->

2nd CIP PLC-5 write to Processor that controls 1756-ENBT card in this rack, copy this to a buffer file
1756-DHRIO--> DH+ -->1756-DHRIO --> backplane -->1756-ENBT --> RsSQL Server

3rd CIP message to RSQL Server

backplane -->1756-ENBT --> RsSQL Server

I think your asking CIP to jump through too many hoops on the command line for the message "communications path" format. If you cannot drill down through your config then its probably a problem going accross these many gateways.
 
controlsdude, that's a good suggestion, however we have only ControlLogix "gateways," with no processor installed. The rack has no intelligence except as a data path. Really, it would be easy if each gateway had a ControlLogix processor installed. One alternative I've considered, although I don't like it, is to send the data to a SLC-5/04 processor on the DH+ network, and have the SLC processor manage the data, which would subsequently be relayed over DH+ to the second gateway, and on to the Ethernet destination RSSQL server. I don't like this idea because it puts an unrelated task on the SLC-5/04 so if that PLC ever gets replaced/upgraded, we could overlook its data handling duties and disrupt communications between the FlexLogix controller and the RSSQL sever. Thanks! Keep the ideas flowing!
 
I would refer you to the 1756-UM514B-EN-P
DH+/Remote I/O Interface Module User Manual

Go to chapter 2 and read about DH+ messaging over remote dh+. I believe the answer is here.

Again, I do not know if you will be able to have one message trigger to your server. I do not think you can bridge through the ethernet by generating an original dh+ message over a remote dh+ network.

communications path is the issue. Try this build a config on your io configuration to the ethernet network and see if you can select it as a path. This is the only lame suggestion I can come up with now. Of course the rsql server would be the an additional path next to the point and click path of the dh+ to ethernet.
 
The other obvious alternative is to install an ethernet card in the flexlogics rack and get an ethernet drop to this panel. Then all this eng time goes away and your done.

just a crude thought.
 
I've looked over some AB tech notes concerning remote DH+ messaging, but have had no luck. The two I'm referencing are tech note ids 16778 and 23887. The second note (I believe) is closest to what I'm trying to do, but the message isn't successful.

Yes, the other alternative is to install another network drop and an additional ethernet card in the first gateway, but I'm attempting to salvage the original plan before abandoning ship since the ethernet addition impacts our installation cost significantly due to multiple gateways that have to be modified...

Thanks for the suggestions!
 
Now I don't have any experience with routing through the DHRIO module but from my understanding this shouldn't be a problem. My only personal experience is routing through Ethernet and Devicenet bridges but I have found that the path is usually the problem.

I would start with a simple DeviceWho message instruction. The Message Type will be CIP Generic and the Service Type will be a DeviceWHO. Make your destination a string. Then vary your communications path and test the message with each of the following. Note that you will have substitute your addresses with what I have. Paths are always 2 parts, the outgoing communications route and the destination.

1. To the Controlnet module, assuming it is right beside of the processor. We will go onto the backplane (1) and into the first slot (1). Substitute your slot number
1,1

2. We will exit through the Controlnet port (2) and go to Node 2 which is our 1756-CNB. Substitute your node number.
1,1,2,2

3. Now we will go onto the Controllogix Gateway's backplane (2) and come out on the DHRIO, I'm going to say slot 6.
1,1,2,2,1,6

4. Now we will go out of this DH+ gateway node and to the other DH+ gateway, let's say node 4. If your are going out on channel A it will be 2 and if your are going out on channel B it will be 3. I'm going to use channel b
1,1,2,2,1,6,3,4

5. Now we will go into the second gateway onto the ENBT, which we will say is in slot 3
1,1,2,2,1,6,3,4,1,3

6. Now we are ready to go to our RsSQL server. Let's say it is on 192.168.0.34
1,1,2,2,1,6,3,4,1,3,2,192.168.0.34

Which step above does the DeviceWHO not work on?

I my have missed something in the paths, perhaps someone can double check me. Here is the basic rundown
1 - Onto the FlexLogix backplane
1 - Slot 1 which is our Controlnet module
2 - Out of the Controlnet port
2 - Into node 2, a 1756-CNB, on the Controlnet network
1 - Onto the backplane of the first gateway
6 - To slot 6, the 1756-DHRIO, of our first gateway
3 - Out Channel B of the 1756-DHRIO
4 - To node 4, the second 1756-DHRIO, on our DH+ network
1 - Onto the backplane of the second gateway
3 - To slot 3, our 1756-ENBT
2 - Out the Ethernet port of our 1756-ENBT
192.168.0.34 - The IP Address of our RsSQL server






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TW Controls -
 
TWControls, I tried the MSG that you recommended, consisting of a Generic CIP message type, with a DeviceWHO service type.

I immediately got the error "16#0013 - Configuration data size too short" when I enabled the message... I don't know which configuration data this is referring to, but I have varied the path by shortening it to a point where I know that our communications work. We currently send messages over the path, CNet_1,2,6,1,0 with no problem, but even that path doesn't seem valid for the DeviceWHO service type. The known good path consists of a message from the FlexLogix CNET module to ControlNet node 6 (which is in the gateway rack), then over the backplane to slot 0, which is the DHRIO card.

My destination tag is set up as a 100 element String data type.

Any ideas?
 
I left out a detail in the destination assignment that is probably causing the problem.

When you say a 100 element string I'm guessing your setup a tag with a name, for example, of MyString with a datatype of STRING[100]. If so then the destination should be MyString[0].DATA[0]

Set your path as CNet_1. This will do a DeviceWHO on the Flexlogix Controlnet module. Not what your looking for but let's get the basics of the message correct first then build on it.

BTW - A DeviceWHO is the same thing that RsLinx does when you do a RsWho

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TW Controls -
 
TWControls

I think your numbers for the paths are correct

I thought the paths were too long. Then their is the amount of data going across controlnet, sucking the bandwidth and causing real control problems maybe.

I think pony probably put an ethernet card and drop to the processor.

 
TWControls, when I did the last thing you recommended last week, I got the error, "Configuration Data Size Too Long" I believe. I remember thinking that is was the opposite message that I got before. That was when I tried to use the DeviceWho command. I really don't think it can be done at this point.
 
pony

Is this the tech note that you used? I did not see where you set up a routing table as it suggested in that write up about DH+.

This is a technote off AB website. And points out setting up routing tables through Contrologix 1756-GTWY software using RSLinx to establish the path.

ID
22632

Products
Communications and Network Products

ControlNet (1786)
Data Highway Plus (DH+)
Ethernet
Modems
RSLinx


Category
General


Date Created
08/29/2002

Last Updated
11/13/2006

Access Level
Everyone

Prev. TN#
A19739313

 
"TWControls, when I did the last thing you recommended last week, I got the error, "Configuration Data Size Too Long" I believe. I remember thinking that is was the opposite message that I got before. That was when I tried to use the DeviceWho command. I really don't think it can be done at this point."

A DeviceWho? I do them all the time. Give me some details to your configuration

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TW Controls -
 
I guess my only point on comms path is that if you can not drill to it on RSLinx, then your probably going to have a problem configuring the path.

I think thats my only last point.

What your saying TWControls is under RSLinx under a DH+ driver you should see all the paths that are available by doing the DeviceWho?

 
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