The slave controller boards are intelligent PC boards that link the PC to any position in the INTERBUS system. This makes it possible to set up powerful visualization stations which allow access to data in the INTERBUS system and the controller close to the application. Several cards can be installed simultaneously in one PC so that it is possible to visualize or monitor several INTERBUS lines in one single PC. The number of data words that the slave controller boards occupy in the INTERBUS system can be set between one and eighteen. The interface cards provide a freely configurable fast I/O channel for time-critical data and also support the INTERBUS parameter channel (PCP). The parameter channel provides an optional access to larger data blocks.