| 摘要 |
PURPOSE:To use a small-capacity backup RAM and to confirm whether control data recorded in the backup RAM is correct or not by extracting partial bits of control data and setting the value, which is obtained by inverting each bit of extracted data, as inverted data. CONSTITUTION:When a control data storing means M2 stores control data in a backup RAM M1, an inverted data storing means M3 extracts and inverts partial bits of this control data and stores the result in the backup RAM M1. At the time of execution of the control, a judging means M4 extracts partial bits corresponding to inverted data from control data recorded in the backup RAM M1 and discriminates whether this extracted data coincides with the value of inverted data in the backup RAM M1 or not; and if it is judged that they coincide with each other, a controlled variable calculating means M5 uses control data in the backup RAM M1 to calculate a controlled variable. Thus, the abnormality of control data is detected to prevent erroneous control though the small-capacity backup RAM M1 is used. |
