A system is presented that facilitates masking data in write data bound for a memory device. The system contains a memory controller and a memory array communicatively coupled to the memory controller. The memory controller sends a write command and write data to the memory array and the memory array updates data contained therein based upon the write command and write data. If the write operation requires a byte mask, the controller sends a byte mask command via a command bus linking the controller and the memory array. Accordingly, separate and dedicated byte mask pins or bus is not necessary to convey byte mask information.