| 摘要 |
An input device in use for electronic calculators with a segment type display section of a plurality of digits comprises a key switch matrix supplied with at least some of the signals applied to the segment of the display section, a latch circuit for detecting the key operation and latching the input signal representative thereof, a control section for detecting the required operation according to the input signal from the latch circuit for performing the required operation in accordance with the input signal and for producing a display signal, and a selector gate circuit which supplies the signal containing key-in detection pulse when the key operation is not detected to the segments and the key switch matrix, and sequentially supplies the key-in judging pulse to the key switches on the column lines of the key switch matrix when the key operation is detected. |
