Memory programmable controller cyclically initiates check for presence of copy protection plug with own serial interface with direct data connection to communications unit serial interface

摘要

The device has a central unit (4) with a processor and a working and program memory, a communications unit (5) with a serial interface (6) and digital and/or analog input/output units (7). A copy protection plug (8) sits on the serial interface with its own serial interface. A direct data connection is connected between the interface for operation. The controller cyclically initiates a check for the presence of the copy protection plug. The data connection is broken at the end of a data exchange.