Abstract: An input/output interface for converting between data patterns in bit-parallel and word-serial format and data patterns in word-parallel and bit-serial format. In combination with a parallel processor, the inputting and outputting rates of the data are to be increased. To this end, a three dimensionally organized memory with a three-dimensional addressing is connected to the input and/or to the output of the parallel processor. Each address is composed of three components, of which a first component represents the significance of a bit, the second component represents the running number of the word in a limited sequence of words, and the third component represents the running number of the sequence, to which the word belongs. A switching network for the control of the memory is associated with the memory. The memory is arranged to buffer an incoming data stream of bit-parallel and word-serial format.