Abstract: A memory device for lighting control purposes, including, for example a battery. The charge of which is controlled by at least one photodetector, which receives light from a lighting means when the latter is in operation. Charging the battery takes place during an operating period of the lighting means. When the latter is not operating, the battery discharges into a light emitting diode. Thus, the information concerning the satisfactory operation of the lighting means is stored for a certain time and after said operation it is possible to check that the latter has taken place. The device has applicability to the control of a public lighting system.