| 摘要 |
PURPOSE:To obtain plural kinds of input with one key and to improve operativity by detecting how many times the key is hit within a specific time. CONSTITUTION:When the key is hit once, a scanning circuit 2 generates a scanning signal for a key matrix 1 at specific intervals. When a key for next candidate selection on the matrix 1 is hit, an encoding circuit 3 detects the key being hit for longer than a keying detection time so as to prevent chattering, an sends out a corresponding code to a bus 4. Further, when the key is hit >=2 times continuously, the circuit 2 generates the scanning signal at specific intervals and when the key for next candidate selection is operated, the circuit 3 detects the key being hit for longer than the detection time. When the key hit for the 1st time and the key hit for the 2nd time are the same and the detection time is shorter than the continuous keying time, the citcuit 3 outputs a code different from that in single keying.
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