Transfer system for data exchange using two active central processing units directly connected together parallel to serial system bus directly connecting CPUs to dispersed devices

A transfer system for data exchange between dispersed devices in stored program controls for process control, comprising:

• devices for configuring, controlling and observing the process, disposed in a remote control area;
• at least two active central processing units;
• at least one active input/output device connected to each central processing unit;
• a serial system bus having a non-persistent access behavior and directly connecting the central processing units to the devices for configuring, controlling and observing, which are disposed in the remote control area;
• at least one lateral bus with priority-persistent access behavior to which the at least two central processing units are connected so that the central processing units are directly connected together parallel to the system bus;
• a plurality of input/output buses, with priority persistent access behavior, at least one of the input/output buses with priority-persistent access behavior being respectively connected to each of the central processing units and to at least one said input/output device, each input/output device having a number of connection units which are connectable with at least one of the input/output buses;
• and sensors and actuators connected to the connection units.