Memory control mode null of katoritsujiraiburari

摘要

PURPOSE:To guarantee memory contents by once saving the address and old operation information of an area, to which writing is executed, in a specified area and afterwards, executing the writing. CONSTITUTION:When the new operation information are written to a memory 5 (in the case of rewriting), the address and old operation information of the area, to which the information are written, are once saved in specified areas 11 and 12 (the old operation information are read from the area, to which the information are written, of the memory and moved to the specified areas 11 and 12 of the memory). Thus, not only when the unexpected interruption of power supply or rapid voltage fall caused by the service interruption occurs, but also when a defect such as the interruption of DC power supply in a control logic step, etc., is generated, the contents of this memory 5 are guaranteed.