Well I officially feel like I am in over my head. I spent some time in October trying to get my communications to and from the humidity sensor to work to no avail. I was tied up with other priorities for a while so I let it go for a while. Just today I thought I would tackle the other part of the issue which is the communications of the PLC too the node. So far I feel like unless I figure out how to create the protocol myself I am going to fail.
The design of this was to allow comms with both micrologix 1400 series and compact logix l32/l35 series plc/pac.
The problems I am having are that the standard the PLC I am using is called ethernet/IP (ip stands for Industrial Protocol not Internet protocol) and it used for CIP (common industrial protocol). From what I have looked into it is a UDP message but it is encapsulated in a different packet. I am attempting to use explicit messaging on port 44818 not the implicit messaging which takes place on port 2222.
I do not know if anyone here knows or is interested in what I want to do but there is more to it than just a stupid ethernet node. There are numerous ways this could become a useful tool. This could be an extremely low cost remote IO interface, an HMI, or an inexpensive serial/usb to ethernet/ip monitoring tool. I know a lot of these things are possible with arduino to arduino comms however, they can really shine in an industrial environment. I colleague of mine just set up an ethernet enabled compact logix plc we got from a scrapped unit in his home for HVAC, pool-hot tub temp control and security control. I plan on doing the same but also want to add an ethernet node to my generator to monitor and control functionality via my plc and the touchscreen in the living room.
Regardless I am going to move forward but if anyone has any ideas that my help me to create a new library for this protocol I would appreciate the help.
art