Abstract: A synchronization system for two active functional units which are interconnected by means of a synchronization connection. In order to obtain reliable synchronization without using an untoward number of wires in the connection, at least one of the two functional units has a generator which is capable of generating three successive discrete signal levels on a single connection wire of the synchronization connection. This function unit also has a detector for detecting a signal transition which is produced by a generator in the other active functional unit and for generating an activation signal in reaction thereto. In response to this activation signal, the generator of the same functional unit produces a succession of two signal transitions from one prevailing extreme signal level to the other extreme signal level of the three successive signal levels.

Abstract: A data buffer memory of the "first-in, first-out" type, having a fixed input by which data are applied to the buffer, and an output bus by which data are extracted from the buffer. The buffer includes logic means whereby a variable output location can be selected. The logic means determines by means of status signals in cooperation with signals applied from outside the buffer, where data are read from the buffer and, if necessary, when data in the buffer are to be shifted further from the input location.

Abstract: A commutation device for the selective control of data transport. At least two data inputs and data outputs, each of the latter having a buffer for storing a data word. A number of possibilities of data transport can be selectively controlled, four for a single connection and two different ones for pair-wise connection. Seven input control lines are provided, two lines for receiving a signal which indicates whether information is present on the associated input line, two lines for indicating the selected output buffer, two erase lines for making a data buffer freely accessible after output of data from the data buffer, and one priority line for granting priority to one of the two input lines if both lines select the same data buffer. There are four output control lines, two lines which indicate that the data present on the input lines have been taken up in the selected output buffer, and two lines which indicate whether an output buffer contains data.

Abstract: A data buffer memory for the first-in, first-out type, having an input bus by which data are supplied to the buffer, and a fixed output from which data are transferred from the buffer. Each section of the buffer includes logic whereby a variable input location can be selected. Status signals are used to determine, in cooperation with signals supplied from outside the buffer, the location where data are to be written in the buffer and when these data in the buffer must be shifted to the output.

Abstract: A data buffer memory of the "first-in, first-out" type, having an input bus by which data are applied to the buffer and an output bus by which data are taken up from the buffer. The buffer includes logic means whereby a variable input location and a variable output location can be selected. The logic means are provided for each section of the buffer and use status signals in co-operation with signals applied from outside the buffer, to determine where data are to be written in the buffer and where data are to be read from the buffer.