Storage system and method for controlling a memory device in order to achieve various characteristics in the same memory device

Method for controlling a PMC memory device, comprising the steps of: - emitting a signal to select each one of several possible modes of operation for the memory device; and - operating the memory device in accordance with the respective selected by the signal mode, wherein, depending on the operation mode, the memory device is set by selection of the current intensity and / or duration of a programming pulse and / or the number of programming pulses in different time long permanently stored states.