| 摘要 |
<p>PURPOSE:To reduce the number of pins of the integrated circuit to make the whole of the device small-size and low-cost, by using one of signal pulse lines, which are connected to a keyboard, as a power supply line also in the device where data is inputted from the keyboard. CONSTITUTION:When operation keys 12 of a keyboard 11 are connected to a power supply line VD, a signal ''1'' (power on) is always inputted to gate circuits G1-Gn from key input signal lines I1-In of operation keys 12; and when a pulse line Cm is ''1'', outputs of gate circuits G1-Gn become ''1''. Consequently, the number of pins of wirings and the integrated circuit which generates signal pulses is reduced.</p> |
