| 摘要 |
<p>PURPOSE:To prevent a pinch roller from being deformed by detecting power-off immediately after a power switch in turned off, executing a power-off reset before a power source of a microcomputer and a power source of a plunger driving device, etc. drop and holding other state than a stop. CONSTITUTION:When a power switch 1 turns off, a voltage of an anode 20 of a diode 16 is varied quickly to a positive voltage in accordance with a relation of a time constant because the time constant of input part of a power-off detecting device 25 is smaller enough than the time constant of a constant-voltage power source device 5. Therefore, sufficiently before the voltage of a power source terminal 19 of a microcomputer 6 drops, the input port 22 of the microcomputer 6 is varied to a H level and the microcomputer 6 detects the power-off and executes the power-off reset processing, by which a cassette tape recorder can be brought to power-off reset before the power source is turned off. In such a way, a state other than a stop state is held and such a problem as a pinch roller is deformed or a cassette half cannot be taken out can be solved.</p> |
