Abstract: A control system includes a nonvolatile memory chip and a controller. The controller transfers a group of data from exterior to the nonvolatile memory chip based on the capacity of the nonvolatile memory, and enables the programming of the transferred data in the nonvolatile memory chip while transferring a new group of data. When transferring the group of data to the memory chip, the controller determines whether all the data are transferred from the exterior to the controller, and, if the all the data are transferred to the controller, transfers the group of data to the memory chip. Also, the controller controls the period of the data programming according to the capacity of the nonvolatile memory. Thus, data transfer and program operations are performed at the same time regardless of the memory capacity.