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Chris Elston

Can't go ONLINE (PLC Programming) to 1756-ENBT/A

18 posts in this topic

This is one of those days where I think I need "two heads are better than one" deals. I've got an 1756-ENBT/A module that has firmware 4, installed I am running version 17.01 RS5000. I can't seem to get a connection through it to PLC program. I have the firmware 4 EDS file installed in RS Lite. I also can ping the module just fine on it's IP address. What did I miss? I would like to PLC program through the 1756-ENBT/A by setting up either an Ethernet driver or Ethernet I/P driver in RS LINX. Linx sees it ok, but it won't drill down into the rack and expose the CPU to go ONLINE. I am only seeing the module at the top level...and I have a head ache today..

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What does the Port Configuration tab look like? Is your computer IP address on the same subnet?

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Here is a screen shot. Yup IP looks good. I can ping the card ok.

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I can also browse the ENBT through HTTP.

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Here is an RS Linx Screen Shot too. No drill down to CPU and back plane.

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Your Robot NIC Subnet Mask needs to be 255.255.255.0 rather than 255.0.0.0?

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I agree, it ought to work. If PING and HTTP work then you've got basic TCP connectivity working. You can specify the LAN in the EtherNet/IP driver but since it's browsing correctly to the top level, the browsing past the module is the problem. Double-triple-quadruple-check the registration of the EDS file. RSLinx Classic uses the EDS to tell it that there's a backplane channel and to display a [+] to allow browsing through it. Version 4 firmware should allow the right-click in RSWho to download and register the EDS directly from the module. I'd also start by shutting down RSLinx Classic and deleting the Harmony.RSH and Harmony.HRC files in the /RSCOMMON directory. These contain the browsing schema and it's possible for them to get corrupted and lead to browsing malfunctions.

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I did an RS Who, then right clicked on the ENBT. All I got was an Upload EDS option, so I did that just to check what the EDS was. It was in fact version 4.0. That was a good sign. I tried blowing away harmony, but still no browse. It acts like it's "trying". I get the "+" then alittle wait, then a "-" with no drill down into the back plane. Any other bags of tricks? Maybe I'll try another firmware version just for kicks and giggles.

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I suppose the backplane connection, or the chassis itself, could be damaged. Do you have time to do a Wireshark capture of the traffic between RSLinx Classic and the 1756-ENBT ?

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I have some time on my hands these days.... can we make this into a teaching / investigation case ? Attached is a screenshot of a simple browse of a small private network with a 1756-ENBT (version 3.9 firmware), 1756-L61, and 1756-DNB attached. This is very similar to your network. I started Wireshark and then manually created the driver, then browsed each layer of the network by hitting the Refresh button. In the Wireshark capture (a *.pcap file zipped for attachment) you'll see Keep-Alive/ACK packets and a few seconds of time separating each layer of the network browse. Step 1 is browsing the node(s) in the Ethernet Devices driver, is shown in Frames 1-28. This includes the initial determination of whether the device is a CSPv4 or a CIP device; you'll see RSLinx attempt to connect to TCP Port 2222 three times. Step 2 is browsing to the backplane to see if there is a backplane connected, shown in Frames 31-40. It seems like this is where your browse fails. Step 3 is browsing the backplane to see what devices are present, in frames 43-64. The controller, DeviceNet bridge, and EtherNet/IP bridge module all show up. Do the same with Wireshark on your machine, and we'll compare. To keep the browse capture simple, use a display filter "ip.addr == 192.168.2.102" (of course substitute your address) and then save the Displayed frames. RSLC_EthernetDevices_Browse2.zip

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Its hard to see on this phone but looks like your computers subset is 255.0.0.0 and the modules is 255.255.255.0. I think you will have to change either one. I would try changing the modules to 255.0.0.0. Then and or swap chassis slot.

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I tried to clamp down on my mask. That didn't seem to help. Also I tried with two PC's one desktop and one laptop and they both do the same. I'll try the slot swap in a second.

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Here is my Wireshark capture. Not sure what I am looking at but it doesn't look the same as yours after the initial first level. ENBT_dump.zip

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I dunno. I may have a Chassis Problem because I believe, I should also be able to drill into the rack through DF1 driver, and I get the same. I can see the Processor, but nothing in the rack.

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Tried flashing down to version 15.0 on the L61 and 3.0 on the ENBT module like Ken Roach, but same results. I didn't flash down the DeviceNET card even though the firmware matrix calls for 6.002 for the DNB card. It doesn't matter anyway. Neither DF1 or ENBT will drill into the chassis. I am confirming that I am using RS Linx Classic 2.54 and RS Logix 17.0 as well. Tried moving the CPU around too, as you can see in this latest setup here.

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How old is the ENBT? I'm a little rusty but wasn't this a symptom of the Amtel processor problem?

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Have you tried pulling the cards and repeating them? This seems to work for me sometimes. I have even changed "faulty"cards and placed them in my test chassis and still have not had problems passing comms..Don't have the answer as to why it stopped working and would not reset in one chassis but works fine in another.

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Figure this out on Friday. So I thought I would post the solution. Basically, I ended up going to my local AB distributor to figure this out and get to the bottom of this. Kudos to Bob Winters at Kendal Electric for helping me out and having some hardware on hand just in case it was the chassis. However the problem was not hardware. I had version 2.54 RS Linx Classic installed on my laptop. When I arrived, Bob tried his laptop, which has 2.55 RS Linx and it connected no problems and drilled into the rack just fine. At this point I assumed all the hardware was ok and it was a software or PC problem. So naturally, I uninstalled 2.54 RS Linx and installed 2.55 version. It worked like a champ. Now according to the Firmware Matrix on AB’s website, for version 17.0, you need a minimum of RS Linx 2.54. I'd say you better bump up to the highest version possible. I did have TWO COMPUTERS if you remember; I had a laptop and a desktop I was trying to connect with. Both had version 2.54 RS Linx. After uninstalling and reinstalling 2.55 on both laptop and desktop I was able to browse the rack. I also was using a crossover cable to eliminate and switch/hub problems. So the lesson learned here is make sure you have the latest version of RS Linx Classic installed on your machine. Why this happened, I dunno. Maybe someone can explain it. Bob thought 2.54 might have been a corrupt install. I would agree with that except, it happened on two machines. I also tried 2.54 on a version 17.0 CPU / 4.008 ENBT. I also downgraded to version 15.0 CPU / 3.9 ENBT neither firmware versions seemed to affect it, until I upgraded to 2.55 RS Linx. I was able to browse the rack with version 2.55 after upgrading back to 17 and 4.008 ENBT as well, so not problems after that. I did also have the latest EDS files installed with RS Linx 2.54 for both CPU and ENBT card. I used the EDS hardware install wizard. I also did try and blow away my harmony as well. None of these suggestions worked until I upgraded to 2.55 RS Linx Classic. Both DF1 driver and Ethernet driver configured in RS Linx Classic was able to drill into the rack after the 2.55 upgrade. So not only did the ENBT not work with 2.54, the DF1 driver would not either. That might be clues to if you experience something similar. Good news is, I am up and working now!

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