MICROCOMPUTER

摘要

PURPOSE:To promptly meet the miscellaneous specification demands of a user and miscellaneous uses, and at the same time, to reduce the scale of a constitution in the aspect of a hardware by arranging a ROM and storage device in address positions which are different from each other on the address space of a CPU. CONSTITUTION:In a case that a data is written in a writable ROM 4, the CPU 1 can be made to execute a prescribed write control processing even during the write operation to the writable ROM 4, by making the CPU 1 jump to other storage device 3 and execute a prescribed write control program stored previously in the device 3, only at that time. Accordingly, a user program region and a data region can be placed in one writable ROM 4, and further, the proportion of the sizes of the respective regions can be optionally selected. Thus, the miscellaneous specification demands of the user can be satisfied promptly, and at the same time, the constitution sale in the aspect of the hardware can be reduced.