JayFree

Hello Ken,   Thank you for the thorough reply. I have been working on this along with many other things (Im actually the process engineer on my tool, not anything to do with hardware or networking but this seemed like a fun challenge haha) but have recently gotten back to it. I kind of came to the conclusion that you did though, that this will be exceedingly difficult and maybe not worth it. We really didnt want to involve the OEM because were running kind of a skunk-works operation, so the less they know the better. But eventually we may inform them and ask them for the upgrade. Although I also realized that the upgrade may be difficult/expensive as well, since our Beckhoff PLC doesnt have a serial output, and one cannot be added in the field easily. That said I did come up with a work around that cost very little money and gives us half of the functionality we need: We have a spare ethernet connection on our Beckhoff PLC and I uploaded an application to run in parallel that just sniffs out the signal of interest going out to the D-net slaves, using the device ID. Anytime the pressure setpoint of that device is changed, this program receives the new value, scales it, puts it into the necessary syntax for our serial devices then outputs it via the spare ethernet cable. I then have an ethernet to serial gateway that just runs the message straight through to the pressure controller. I tested it yesterday and it worked great. So now I am able to set the pressure using the HMI to our new pressure controllers. I just leave our old pressure controller connected to the D-Net so the tool is none-the-wiser. The only problem is that I dont get the feedback that the pressure has reached the setpoint, since I cant figure out how to send the signal from our new controller back into the D-net data stream, especially since its polling and it would get overwritten by the value from our old pressure controller immediately. But for now I got what I needed. I may still work on the D-net to serial gateway in my spare time, or just let the OEM work on it.   Anyway, I appreciate the insight. I had barely heard of device net before taking this on and I learned a lot. If youre willing to speak directly (free of charge obviously haha) I would be interested in hearing your thoughts.

Hello, I have a tool that communicates to several slave devices over D-net. The PLC is a Beckhoff, and any configuration of the PLC is inaccessible by anyone except the OEM of the tool. We want to swap out 2 slaves (pressure controllers) for another pressure controller but there is not a drop-in replacement that can do what we need it to do. The only controller capable of what we need communicates through RS232. We want to adjust and monitor the pressure setpoint and measurement with our standard HMI, through the D-net network. Therefore I need to convert the D-net signal into a usable command and send it via RS232 to the controller. The controllers manual lays out how the messages needs to be formatted when coming in from the RS232. I purchased this unit: https://www.mksinst.com/f/rs232-to-devicenet-gateways That can take in D-net and out put RS232, and can be configured to do reformatting of the signal but I need to know what the signals looks like coming through our D-net so I can then take the relevant pieces and then add/remove the rest and send it along through the RS232 to our new controller. I am in the semiconductor world and was told that the communication between master and slave is "standard Group 2 only" protocol, and I have searched to find out what this means for our specific devices but have come up empty. Is there a way read the data stream with some software or secondary device or is there an example of the sequence of data that is standard to "Group 2 only" I have found some guides online but I am not int he networking world and I dont quite understand them (see attached).   Thanks! v1Ch4.PDF