Abstract: A redundancy address in a plurality of memory devices is identified by at least two protocols available in an electric system. The first protocol is a mode register set command (or extended mode register set command). A chip select signal determines one of a plurality of memory modules, where a memory device is identified with at least one data port. Alternatively, a data strobe port or a data mask port may be preferably used for the selection of the memory devices instead of using the data port. The second protocol is a RAM access command which identifies a defective memory cell address (redundancy address) within the selected RAM by way of a plurality of address ports (ADRs). A redundancy address programming method is realized by way of electrically programmable fuses or by dynamically programmable redundancy latches integrated in each memory. The electric system configuration preferably includes a non-volatile storage device for storing a data port organization for the memory devices.