| 摘要 |
PURPOSE:To reduce the load of an operator and at the same time to prevent the erasion of data on a recording medium by writing the using quantity information of the recording medium to a specific part of the medium and reading out said information in an active mode to display the used quantity of the recording medium. CONSTITUTION:The using quantity information of a recording medium 6, i.e., the using frequency (passing frequency) of the medium 6 and the data when the oldest data is written are written at a specific part of the medium 6. In case the medium 6 of an external storage device 7 is exchanged by a program of an operator, the using quantity information of the medium 6 is read out of the specific part of the medium 6 for each exchange or each application of electric power supply. Based on this information, the using frequency and the time elapsed are displayed at a display part 8a of a display device 8. The using frequency is added every time the medium 6 is used in accordance with use of the device 7. This addition is repeated for each application of power supply and every replacement of the medium 6. Thus the using frequency is accumulated with replacement at the specific part of the medium 6. |
