| 摘要 |
PURPOSE:To read precisely data by providing a special control part and writing data in RAM accurately even if a voltage drops during the writing operation. CONSTITUTION:A comparator 7 decreases in output level from L to H if the output of a boosting circuit drops below the 2nd level temporarily while a CPU sends out H to a line 27a and data is written in the RAM23. This is transmitted to an input D of a DFF25-3 through a line 28. The clock terminal of the DFF25-3 is connected to a line 27e, to which a pulse is inputted every time one step of a program is executed, so even if the signal on the line 28 has transition from L to H during the writing operation, the DFF25-3 does not respond to the signal on the line 28 until the writing step is completed and holds its Q output at L throughout the writing operation. Consequently, data is read precisely even if the power output drops. |
