| 摘要 |
PURPOSE:To set a specific key input mode and an all key input mode selectively, by giving a set signal to one of two counters by a key scanning stop circuit to scan only partial specific keys. CONSTITUTION:Clock pulses from an oscillating circuit 2 are counted by an X counter 3. A Y counter 4 is reset by a key scanning stop circuit 13 and is stopped in the position. Thus, even if the X counter 3 becomes a full count to issue a carry out output 11 of the carry signal, the output of the Y counte 4 is fixed. When a key switch in the position where the X-direction line started by an X decoder 5 and the connection line of a Y multiplexer 6 intersect each other is depressed, a coincidence signal 10 is outputted. Oscillation of the oscillator 2 is stopped by the coincidence signal 10, and outputs of the X counter 3 and the Y counter 4 at this time are stored in a storage circuit 7 and are converted by a converting circuit 8. |
