| 摘要 |
PURPOSE:To improve control characteristics by latching a reference signal, a regeneration control signal and an FG signal in a measuring counter, inputting the signals into a microcomputer, comparing the reference signal with the FG signal, and performing D/A conversion. CONSTITUTION:A measuring counter 11 houses a circuit having a latching function. A reference signal (a), a regeneration control signal (b) (e.g., a frequency signal obtained from running magnetic tape) and an FG signal (c) (e.g., a frequency signal obtained from a capastan for driving the magnetic tape) from the outside are latched and measured. The signals are inputted into interrupting signal terminals INT1-INT3 of a microcomputer 12. The data which are latched with the measuring counter 11 are inputted into the microcomputer 12 through a bus line 13. Then, operation for phase control is performed based on the reference signal and the FG signal. D/A conversion is performed in a D/A converter 14. The result is outputted as a phase comparison output. Thus the phase control characteristic is improved effectively. |
