| 摘要 |
PURPOSE:To enlarge preserved data by performing compression and restoration of data by using a method of difference value expression or continuous expression. CONSTITUTION:The value of the preceding time is stored in a previous time value register 1 at timing in which input data of the value of this time is read freshly. A subtracter 2 determines the difference between the value of the register 1 and data of the value of this time and inputs to a controlling circuit 3. A reference value mode and a difference value mode are discriminated according to whether the data input is the first time or continuous mode, and a group of output PACK data are determined and outputted successively. In the case of the reference value mode, two PACK data are read, and set respectively to upper and lower byte of register 14 of the value of this time through a switching device 13, and outputted as output data of the value of this time. In the case of the difference value mode, said data are set to the register of the value of this time, and outputted as output data of the value of this time. |
