Control block with point-to-point communication between a control master module which is activated on a data bus and expansion slave modules

The block has an input/output expansion slave module (200) comprising a processing logic unit and two signal ports (113-1, 113-2). A control master module possesses a set of signal ports (113-3 to 113-4), and a control logic unit for data exchange with the data bus. The module is connected to the expansion slave module such that each additional signal port of the latter set of signal ports is connected to a respective signal port of one of the signal ports of the subsequent module.