Printer with a memory management unit and memory management unit

摘要

PURPOSE:To obtain a printer having a function of properly managing a large amount of printing data or the like registered and stored. CONSTITUTION:When an occupying ratio of printing data or the like in a memory exceeds a predetermined amount alpha (1), data having the oldest history of use is compressed and stored in an unused area (2). When the data stored in a compressed state is to be used, the compressed data is expanded to be made available (4). On the other hand, when the overflow of the memory storing the data occurs, an empty area is ensured in the memory by erasing a part of data having the oldest history of use other than attribute information, and the content of the attribute information of the erased data is indicated.