When using a SLC with Ethernet, it does not use true TCP/IP, but sort of a subset. We have run into problems integerating a metal assembly line with these and other ethernet products. According to our vendors, they don't seem able to
make connections with them and issue commands over standard TCP/IP. Does anyone else out there have this experience?

Scott Barrett
Sr. Controls Engineer

 

First you have to tell us if you are using the RSLinx package to communicate with these devices? I believe that AB sends DF1 packets wrapped inside a TCP/IP packet, which RSLinx decodes for you.

 

> First you have to tell us if you are using the RSLinx package to communicate with these devices? I believe that AB sends DF1 packets wrapped inside a TCP/IP packet, which RSLinx decodes for you.<

I believe you are right. I had a project last year using a 5/05 on a chemical plants ethernet. We used 2 NT workstations and Intellution for the HMI. It required a version of RSLinx, an OEM package setup for Intellution. I didn't get into the details at the time. After I set the IP address I could ping it on a local cable. It took my client's network people awhile to get the correct submask etc. It works well for programming as well as for HMI after the inital startup woes.

 

Hi Scott:

I think I can help you somewhat. I have reverse engineered the AB Ethernet protocol used on the SLC's and the PLC-5's. The source-code results of my work is available at http://freshmeat.net/appindex/1999/11/07/941993013.html

This source code is designed around Linux but I have received several reports that it ports quite cleanly to Win32.

If you have any questions, you may reach me at my office through the 8 line - 8-280-6325 (Powertrain Bay City).

--
Ron Gage - Saginaw, MI
([email protected])


P.S. The code was developed long before I started working for GM so it is
freely available without restrictions.

 

What kind of 'commands' are your vendors trying to send ? I can assure you, the 5/05 does have a true standard TCP/IP stack - though, like most products, does not implement the full suite of application protocols....

Dan Hazel
Rockwell Automation

 

If I understand you, my experience is exact opposite. I've connected with SLC 5/05 using strict Berkley Socket API. Of course you have to
know or reverse engineer the proprietary connection and transaction headers/packets, but it is a simple TCP/IP encapsulation.

Jerry

------------------------------------------------------------
Jerry M Baucum
Bullet Software
3213 Peppertree Pl.
Plano, TX 75074, USA
Tel: (972) 633-9111
Fax: (972) 633-9112
Email: [email protected]
Web: www.bulletsw.com

 

What we were trying to do is connect a marquee with ethernet compatibility with my SLC5/05. It did not connect and work. What I received from the vendor was that they knew about it, and it was with the AB TCP/IP. I was also hoping to
FTP to the processors to do backups of all the line on a periodic basis without lots of cost, confusion, or complication from our floor people (I will end up doing this with a macro program and NTScheduler).

What we normally use is the RSLinx/Networkx500 combo, so it is not a communication problem.

 

Unless the marquee you are using was designed to communicate to the SLC 5/05, I wouldn't expect it to work just because they both support TCP/IP. TCP/IP is only a carrier protocol, it does not specify how the data in the packet should be laid out.

Furthermore, FTP (file transfer protocol) was originally designed for UNIX/VAX systems to exchange files between systems. This protocol has not been built into any TCP/IP based Automation device with the exception of the Pyramid Integrator's MicroVax module and the PLC 5 co-processor module. (please correct me if I'm wrong,.. I'd be extremely interested in a PLC that did support FTP/telnet)

As far as doing remote backup's of you ladder programs, I think Rockwell Automation has a product called RSGuardian that might do the trick. I'm sure there are also third party products as well that will upload and
backup/compare the ladder programs with a backup file.

Christopher Di Biase
[email protected]

 

> At07:58 AM 5/4/2000 -0400, Scott Barrett wrote:
> >What we were trying to do is connect a marquee with ethernet
> compatibility with my SLC5/05. It did not connect and work.

You could add a serial Device Server (DS) - a small serial to ethernet converter on the serial port of the SLC5/05, then set the serial port up to dump raw ASCII messages out for the marquee. The DS can be set to auto connect to the the IP/port of the marquee and forward the ASCII text.

Yes, that seems silly since you have a direct Ethernet port, but it may be the simpliest method.

> What I received from the vendor was
> >that they knew about it, and it was with the AB TCP/IP. I was also hoping to
> >FTP to the processors to do backups of all the line on a periodic basis without
> >lots of cost, confusion, or complication from our floor people (I will end up
> >doing this with a macro program and NTScheduler).

I doubt the SLC5/05 supports FTP - at least not for program dumps.

 

<snip>
-> As far as doing remote backup's of you ladder programs, I
-> think Rockwell Automation has a product called RSGuardian
-> that might do the trick.


Anything that will do the same thing without the ridiculously high price attached?

 

As far as backups, what I am ending up looking at is making a macro with an outside utility to actually do the backing up (including archiving the last few backups, just in case) for 4 processors. This way, I can connect to each in
Logix500 and put the file in the appropriate directory. I also have 7 Fanuc robots on this line that I will connect to via FTP and do the same thing. All this will be under WinNT Scheduler at whatever interval my trades think is
necessary. And all at low cost. I just gotta find a good macro program.

Thanks for all the information. This is my first trip into a networked world. I will not say it was easy, but we are making it through.

Scott

 

where would one find which protocols the SLC does support? I am currently reverse engineering it but, I'm sure the information has to be out there