An area detection unit detects a main rectangular area to which an access start address indicated by one-dimensional access information is included among main rectangular areas corresponding to two-dimensional access information. An address conversion unit divides the detected main rectangular area into sub rectangular areas, detects a sub rectangular area to which the access start address indicated by the one-dimensional access information is included, and converts the one-dimensional access information into first two-dimensional access information based on a relative position of the sub rectangular area being detected. A memory controller receives the first and second two-dimensional access information, and converts the two-dimensional access information into an access address. Accordingly, a modification of a memory controller accessing a semiconductor memory by receiving the two-dimensional access information becomes unnecessary. As a result, existing design properties can be effectively utilized, and a development period of a system can be reduced.