Memory device systems, systems and methods are disclosed, such as those involving a plurality of stacked memory device dice and a logic die connected to each other through a plurality of conductors. The logic die serves, for example, as a memory interface device to a memory access device, such as a processor. The logic die can include a command register that allows selective operation in either of two modes. In a direct mode, conventional command signals as well as row and column address signals are applied to the logic die, and the logic die can essentially couple these signals directly to the memory device dice. In an indirect mode, a packet containing a command and a composite address are applied to the logic die, and the logic die can decode the command and composite address to apply conventional command signals as well as row and column address signals to the memory device dice.