Abstract: A procedure for operating an external data storage unit comprising at least one stationary computer unit and one external data storage unit connectable to the computer unit via a port and a data connection. In the stationary computer unit, an operating program substantially continuously monitors possible ports for a data connection with an external data storage unit and, simultaneously, in case of a data connection via a port with an external data storage unit, monitors whether a pulse generator on the external data storage unit connected to the data connection has generated a voltage pulse. The abstract of the disclosure is submitted herewith as required by 37 C.F.R. §1.72(b). As stated in 37 C.F.R. §1.72(b): A brief abstract of the technical disclosure in the specification must commence on a separate sheet, preferably following the claims, under the heading “Abstract of the Disclosure.