Mike

... from cyclic process image to none That seems to work - I can now write to the process image (e.g. IB0) and it sticks. I now need to devise a flag for the plc so it can detect if it's a real plc (and just copy the peripheral values at the start of OB1) or not (and wait for NetToPLCSim to write to IB0 etc). That way I won't have to remember to change OB1 depending on whether it's the real PLC or PLCSim . I think I need to check if there's a downside to setting "cyclic process" to "none". (Detection...

Great project - thanks for developing and maintaining it. I need to be able to do the same as changing a value in PLCSim (S7-1200) sim table for the actual I/O. We have a working Visual Studio plant simulator which can access an S7-300 PLCSim through S7ProSim but we want to upgrade to an S7-1200 and still use our VS simulator. Is it possible to get the S7-1200 PLCSim to change a peripheral input like %I0.0:P (digital) or %IW64:P (analogue)? Using S7NetPlus (through NetToPLCSim) writing I0.0 or IB0...