tkamrath
Member
I am using libnodave to communicate with a 1214 S7-1200 PLC via the builtin ethernet port. It is working fine for a single instance of my .net C# program. And I have it working on a PC and on a CE panel device. But what is not working is multiple connections. So when I run one instance the connection is successfull. When I start the second instance I cannot get a connection. Then when I kill the first instance the second instance gets connected. I think the problem has something to do with the ISO packet. My question is how do I change the code in libnodave to allow for multiple connections?
There is parameter in the ISO packet that tells the 1200 what connection mode to use. In the libnodave _daveConnectPLCTCP function the packet data is somewhat documented for the CP243 communications and this parameter is there. But I don't know where this parameter is in the regular TCP ISO packet. I think the default for this parameter is 1 (PG) and I need to change it to 2 (OP) so that the 1200 will support up to 3 connections. Can anyone tell me where this parameter is in the TCP ISO packet data block so I can change it?
There is parameter in the ISO packet that tells the 1200 what connection mode to use. In the libnodave _daveConnectPLCTCP function the packet data is somewhat documented for the CP243 communications and this parameter is there. But I don't know where this parameter is in the regular TCP ISO packet. I think the default for this parameter is 1 (PG) and I need to change it to 2 (OP) so that the 1200 will support up to 3 connections. Can anyone tell me where this parameter is in the TCP ISO packet data block so I can change it?