I am running a process on a S7-1200 plc and I need it to send a start signal to my python script, after the script is done running it needs to send something back to the plc to initiate the next phase. Oh, and it has to be done in ladder.
Is there a quick and dirty way to send things over profibus or am I better off using just a RS232 thing?
After failing with libnodave and OPC, I created a TCON,TSEND and TRECV communication thing. It transmits a byte over TCP and it works.