This scenario is perhaps the simplest one. Here, the PC controls (or monitors) a machine, much like a PLC might.
Example of simple hardware configuration: PC with inserted relay I/O card, switching on lights and taking photos of some process everytime something interesting happens (e.g. lab mouse comes to take food).
Usually, it would consist of a single logic module (for instance the IL language) and a single I/O module.
Alternately, one might use the python scripting language instead of a logic module, thus getting roughly the equivalent of a VB+OPC environment.
Optional additions are some sort of communication, for instance Modbus or one of the CIF cards, and the DSP module for PID and general floating-point operations.
$Date: 2004/12/28 05:32:13 $