Red Lion DSP for protocol conversion

[Fredlaroche]

I'm trying to fix an old custom machine which had been working forever here and which no one actually knows how it works...

We had a compactlogix PLC talking to a old SLC5 that was then talking to Parker GV6K motion controllers... I guess Compact logix Ethernet isn't speaking to TCP/IP GV6K ports...

I have a DSP from Red Lion on hand and I would be tempted to try and use it to minimize modifications to the software and get this thing running again.

From my understanding, the DSP should be able to read from the compactlogix and write to the GV6K

Anyone worked with this before? Any tips I should know about?

Thanks

 

[krakenfan69]

The DSP will read naitive tags from the Compact Logix. Save the CLX file as an *.L5K file and once you choose the driver import the tags and tell it how to find the CLX and you have all your tags available. Make sure you are using the latest build of Crimson (Gold Build 599) as it addresses some comms issues they recently resolved. The nice thing is when you download to it it will preform a flash upgrade too. Not familiar with the Parker so I can't help you there. The webserver in the DSP makes it nice to create some diagnostic pages that can accessed remotely too!

Hope that helps some,

Kraken Fan #69

 

[Fredlaroche]

Thanks a lot, that's already helping a lot!

 

[krakenfan69]

I was told I dint need to create tags in the DSP and that I could just point my RS-232 Modbus registers to the native l5k Giles but never managed to do it. I ended up creating internal tags then pointing them at the l5k tags to be updated. Then on the 232 side chose slave device holding registers that were in turn updated by the internal Red Lipn tags. For what it's worth the Red Alison tech support is really helpful with things like this. That's how I learned how!

Kraken Fan #69

 

[Fredlaroche]

Allright, I managed to get my CompactLogix and my Red Lion module to talk. I can see the tags as they update on the live display in CRIMSON.

As for the parker drive, I can ping them so I know we are on the same network... but I can't get any info to OR from them.

When we had the SLC5, the drive would send a WRITE request or a READ request to the SLC5. The command was structured in that sequence: # of the file, # of starting bit to send, # of bits to send, # or first internal bit to receive.

It's like it was meant to work specifically with AB SLC5... I'm at a loss right now. Should I try to create internal tags that follow the same numbering as AB? Any ideas?

 

[krakenfan69]

I'm not sure. If you want to post your file I can take a look and see if anything pops out. No promises it will help but I'll try...

Kraken Fan #69

 

[Eddie Willers]

The same "Read N7:0" command can use a different "PCCC Command Code" depending on whether you're sending it to a PLC-5 or an SLC-500. Maybe the Parker controller implemented a very specific command code.

I agree; let's have a look at the original SLC-500 program.

 

[Fredlaroche]

The same "Read N7:0" command can use a different "PCCC Command Code" depending on whether you're sending it to a PLC-5 or an SLC-500. Maybe the Parker controller implemented a very specific command code.

I agree; let's have a look at the original SLC-500 program.

The SLC5 program won't tell much. It's just 3 MOVE commands that takes the data received from the CompactLogix message and moves it to the proper files that are interrogated by the Parker drive. The n7:2 word is sent to B3:0 because it has the binary commands and the others are sent to N10:0 and onwards.

In the parker drive, the commande specifically points to file 3 for binaries and file 10 for integers.

Both are actually pretty damn simple. It really DOES look like the parker drive was meant specifically to point to those Allen Bradley program files. Even the HELP file that describes the READ and WRITE command lines mentions Allen-Bradley file numbering...

Was I don't get is that the DSP actually offers a driver for this type of drive, and while you cannot access every parameter from this driver, they list the VARBs and VARI's (Binary variables and Integer Variables) as available. I would have thought that the DSP would have the capabilities of WRITING and READING into those parameters, but since my older application was doing the opposite (i.e. the drive would do the reading and writing), I don't know if it's at all possible.


I'm gonna include my CRIMSON file here. Please don't mind the Tag names as they are in french but as I said, this part works fine. Compact Logix to DSP is OK.

Let me know if you see anything

(damn, that turned into a wall of text... might be the Friday morning coffee...)

 

[Eddie Willers]

Thanks for clarifying that the Parker controller is initiating the communications with the SLC-5/05 controller. I made an incorrect assumption that the SLC-5/05 was using MSG instructions.

Is it doing that over Ethernet ?

If so, they almost certainly implemented a subset of the old "CSPv4" protocol, using TCP port 2222. The ControlLogix made a clean break with that protocol at the beginning (1997 !) and no ControlLogix family controller supports it.

Can you capture some of the traffic between the two devices with Wireshark ?

 

[Fredlaroche]

Hey Eddie, I'm not familiar with Wireshark at all but been checking out a few videos on the website after reading your comment. I may set it up for a capture later today! Let's see what we find out there.

As for the protocols... In order to PING the Parker drives, I had to run an ARP command in my command prompt. does that say anything?

 

[Eddie Willers]

To emulate what the SLC-5/05 was doing, I recommend configuring the "DF1 Slave" protocol as one of the Protocols on the Data Station Plus Ethernet network port.

The name "DF1 Slave" is a bit of a misnomer, since that's really a variation of the DF1 protocol over a serial port. It's really the CSPv4 protocol on TCP Port 2222, acting as a "peer" or "receiver" rather than as the message initiator or "master".

You'll then be able to configure Data Blocks for that driver, with B3 or N7 sort of starting addresses, and a "Device to G3" direction.

 

[Fredlaroche]

To emulate what the SLC-5/05 was doing, I recommend configuring the "DF1 Slave" protocol as one of the Protocols on the Data Station Plus Ethernet network port.

The name "DF1 Slave" is a bit of a misnomer, since that's really a variation of the DF1 protocol over a serial port. It's really the CSPv4 protocol on TCP Port 2222, acting as a "peer" or "receiver" rather than as the message initiator or "master".

You'll then be able to configure Data Blocks for that driver, with B3 or N7 sort of starting addresses, and a "Device to G3" direction.

If I understand correctly, you are suggesting I scrap the protocol with the PARKER driver and that I replace it with the DF1 slave driver and set up tags as I would have done in their respective files had I done it in Logix 500???

...That actually makes a lot of sense!!

I'll just go ahead and try this.

thanks

 

[Fredlaroche]

Another quick follow up:
I have tried what Eddie suggested and it doesn't work for me so far... still trying to figure this out... Have put Red Lion tech sup. in the loop, they haven't been much help so far but I'm hoping they find something

 

[Eddie Willers]

You might have to get Wireshark in between the devices.

Look into getting an Ethernet switch with port mirroring. An inexpensive one will do, for these purposes.

The Netgear GS105E "Unmanaged Plus" switch has some port mirroring and is cheap and simple. See it in action on Youtube.

I also like my tiny USB-powered DualComm switch with permanently-mirrored ports.

 

[Eddie Willers]

Also, try making the data blocks bigger than you expect them to be. The Parker driver might round up to a larger block read (10 or 16 or 32 words) than reading the exact number of words, or individual words.