Abstract: A method and a circuit arrangement are disclosed for transmitting binary signals between peripheral units which are connected to one another via a central bus line system. The signal transmission is to take place without the necessity of including a central processor, which is likewise connected to the central bus system. For this purpose, it is provided that signal transmission requests from the individual peripheral units are transmitted to a memory access device which is also connected to the central bus line system and which, in response to the receipt of such transmission request, de-activates the central processor in respect of the transmission of signals to the central bus line system.

Abstract: In a teleprinter private branch exchange having a communications unit, to which teleprinter terminals are connected, a central unit and a storage unit, the load due to connections between the individual units on a bus connecting the individual units together is kept as low as possible. For this purpose, the individual units are connected to the bus through the processing systems such that the processing unit of the central unit controls the connection of the processing units of the other two units using the bus for just one signal transmission. It is also provided that the processing unit of the central unit also triggers the execution of the procedures to be executed in the communications unit and supplies the addresses of those storage areas in the storage unit in which associated signals are to be stored or are stored.