Heterogeneous interconnection of the QNX systems and PLC in distributed control systems

In the following article the project of solution of distributed control system is described in which the operating system QNX in the connection with industrial bus CAN and industrial controllers PLC is used. Two ways of control system project are discussed there, The first one makes use of industrial computers of the PC type and industrial buses with intelligent sensors and actuators, the second project includes in this network also the industrial controllers PLC. With the interconnection of both possibilities we obtain the third solution which provides the advantages of both previous ones what is the high computing capacity of industrial computer and the capability of programmable controller to work in real time. Copyright (C) 2000 IFAC.