Soft-commissioning: hardware-in-the-loop-based verification of controller software

The basic idea of soft-commissioning (SoftCom) is to test industrial control software by connecting a controller, e.g. a PLC (Programmable Logic Controller) to a commercial discrete event simulator (DES), which provides system reactions and sensor signals similar to the behavior of real hardware, e.g. an industrial manufacturing line. In order to establish a connection between simulator and PLC, a modular architecture was developed. The basis of this modular system is a communication protocol common to all members. The two basic modules are the I/O device driver (IODD), which is used to interface between the I/O hardware and the SoftCom protocol, and the simulator to real world interface (SWI). The SWI is used to link the simulator to the SoftCom system.