JPS59201251A - Music selecting circuit device in tape deck - Google Patents

Abstract

PURPOSE:To select all pieces of music anywhere music selecting operation is started, and perform effectively the music selecting operation by providing a music end detecting function, music starting function, and automatic blank skipping function. CONSTITUTION:When a mode signal is changed into program search mode in the middle of some piece of music, a pulse signal which is outputted from a differentiation circuit 41 and means the end of music is outputted from an output terminal 55 through an AND circuit 44. When a play mode is entered by this signal, pulse signals outputted from differentiation circuits 42 and 41 are inhibited to pass through AND circuits 45 and 44, so that the start and end of music are ignored. When, however, a blank state continues for a specific time after the end of music, a pulse signal outputted from a differentiation circuit 43 is outputted as a blank skip signal from an output terminal 57 through an AND circuit 46, and the mode signal is inverted into program search mode.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a music selection circuit device in a tape deck, particularly a tape deck that detects the end or start of a music piece recorded on a cassette tape or the like and outputs a signal necessary for music selection operation. The song selection circuit device has a function to detect the end of a song based on the audio signal, a function to detect the start of one song, and an automatic blank skip function (when an unrecorded section continues for a predetermined period of time, it automatically starts the next song). The present invention relates to a music selection circuit device in a tape deck having a function of outputting a signal for shifting to a skip operation to find a song.

Conventionally, a semiconductor integrated circuit as shown in FIG. 1 has been known which detects the unrecorded portion of a cassette tape or the like between tracks and outputs a track interval detection signal for performing a music selection operation on a tape deck. . In the semiconductor integrated circuit ICI shown in FIG. 1, 1 is an input terminal into which an audio signal is input, 2 is a limiter amplifier, 3 is an IJ limiter amplifier output terminal, 4 is a switch circuit, 5 is a CR terminal, 6 is a power supply terminal, 7 is a control input terminal, 8 is a control circuit that controls the power supply reset and music selection start operation, 9 is a ground terminal, 10 is a noise filter terminal, and 11 is an output terminal for detecting between songs. What the signal is output from.

12 and 13 are comparators, 14 and 15 are flip
Flops, 16 and 17 are OR circuits, 18 to 22
represents a transistor. Also.

2 connected to each terminal of the above semiconductor integrated circuit ■C1
3 to 26 are capacitors, 27 to 29 are resistors, 3
0 represents a music selection operation switch.

The operation of the conventional example shown in FIG. 1 will be explained with reference to the timing chart shown in FIG. In addition, (α) in Figure 2
1 indicates the audio signal input to the input terminal 1 above.
Arrow A in the figure indicates a recording section, and arrow B indicates a non-recording section. Also, (b) shows the voltage waveform at the CR terminal 5, (C) shows the voltage waveform at the noise filter terminal 10, and (d) shows the inter-song detection signal output from the output terminal 11. The start of the 9-music detection operation is performed by synchronizing the power on or by turning off the music selection operation switch 30 externally connected to the control input terminal 7 during one energization state. When the track interval detection operation is started and the tape is running through the recording section, the transistor 18 is turned on by the operation of the switch circuit 4, and the voltage at the CR terminal 5 is maintained at rLJ. Also, when it comes to the non-recording part, the transistor 1
8 is turned off, and the capacitor 24 is charged up by the time constant of the capacitor 24 and the resistor 28 externally connected to the CR terminal 5. That is, the voltage at the CR terminal 5 changes as shown in FIG. 2(b) corresponding to the recording section and the non-recording section. and.

When the voltage at the CR terminal 5 reaches a predetermined threshold Vc, the output of the comparator 12 becomes rHJ and the shift flip-flop 15 is set. When the flip-flop 15 is set, its output becomes rLJ and the transistor 20 is turned off, so the output of the output terminal 11 becomes "H" as shown in FIG. 2(d). Become.

Next, the voltage at the noise filter terminal 10 (Fig. 2(c)
) (shown) will be explained. When the tape reaches the recording section by running, the signal of the recording section (Fig. 2 (a) A
) is input to the limiter amplifier 2, and the limiter amplifier 2
If the output of the switch circuit exceeds the judgment voltage of the switch circuit, noise and
A capacitor 26 externally connected to the filter terminal 10 is charged up.

The charged-up voltage has a predetermined threshold value V,
When it becomes higher than n, the output of comparator 13 becomes rHJ, flip-flop 14 is set, and flip-flop 15 is set. By setting the flip-flop 14, its output becomes rL
J, the transistor 21 is turned on. As a result, the capacitor 26 externally connected to the noise filter terminal 10 is discharged, and the voltage at the noise filter terminal 10 becomes rLJ. Also, by resetting the flip-flop 15, its output Q
is rHJ, and the transistor 20 is turned on. As a result, the output from the output terminal 11 becomes rLJ as shown in FIG. 2(ti). In this way, the inter-song detection signal as shown in FIG. 2(d) corresponding to the unrecorded portion is obtained from the output terminal 11, and based on the inter-song detection signal.

A music selection operation is performed on the tape deck. In addition.

In the part shown by arrow C in FIG. 2(b), the detection time between nine songs is not performed because the detection time of the unrecorded portion is short. Also.

The part shown by the arrow 07 in FIG. 2(c) is charged up by the noise shown by the arrow C' in FIG.
7, the one-track detection signal has not been inverted to rLJ.

The conventional example shown in FIG. 1 described above is reasonably effective as a tape cue program for selecting songs.

This has the advantage of preventing song selection errors due to noise, but if you start the song selection function (hereinafter referred to as blank skip) from an unrecorded section, the 9-track interval detection will detect the blank between songs after passing through the first recorded section. Since it is performed from the beginning, there is a drawback that the first song is often poorly selected. Also, CR terminal 5. Control input terminal 7. A drawback is that many external components such as capacitors and resistors are required for the noise filter terminal 10 and the like.

The present invention aims to solve the above-mentioned drawbacks.
Song End Detection Function Equipped with two song start detection functions and an automatic blank/skip function, the start detection function described above allows all song selections, including the song immediately after the song selection operation starts, to be performed no matter where the song selection operation starts. The automatic blank/skip function mentioned above automatically starts blank/skip when a predetermined period of time has elapsed from the detection of the end of a song even if there is an unrecorded section for a long time, allowing for effective song selection. It is an object of the present invention to provide a music selection circuit device for a tape deck, which can reduce costs by minimizing the number of external components. This will be explained below with reference to the drawings.

FIG. 3 shows the configuration of an embodiment of the present invention, and FIG. 4 shows a timing chart for explaining the operation of the embodiment shown in FIG. The symbol IC2 in the figure is the circuit device 31 of the present invention.
is an input terminal, 32 is an inverting operational amplifier, 33 is a comparator, 3
4 is a clock oscillator.

35 to 37 are timers, 38 to 40 are flip
Flops 41 to 43 are differentiating circuits.

44 to 46 are AND circuits, and 47 is an inverter.

Reference numeral 48 denotes an MSF terminal to which mode signals (cue detection mode and play mode) are input.

49 is an analog switch which connects the MSF terminal 48
50 is a changeover switch that switches the gain of the inverting operational amplifier 32 based on a mode signal input to the inverting operational amplifier 32;
51 and 52 are resistors, 53 is a power supply terminal, 5-4 is a ground terminal, 55 to 57 are output terminals, 58 and 59 are capacitors, and 60 is a resistor.

The operation of the embodiment shown in FIG. 3 will be described with reference to the timing chart shown in FIG. In addition, (,) in Figure 4
or s5 represents the signal waveform at arrow (α) or s5 shown in FIG. 3, respectively.

In FIG. 3, capacitor 59. The reproduced audio signal inputted through the resistor 60° input terminal 31 is amplified by the 1-inverting operational amplifier 32 and sent to the comparator 33 (the output signal of the inverting operational amplifier 32 is shown in FIG. 4 (α)). ing). and.

Comparison processing is performed in the comparator 33, and the comparator 33
From this, a signal as shown in FIG. 4(b) is output.

The output of comparator 33 resets timer 35 and flip-flop 38. Also.

A clock signal as shown in FIG. 4(c) is supplied from the clock oscillator 34 to the timer 35 and timers 36 and 37 described later. Therefore, when the output of the comparator 33 becomes "0" (corresponding to the unrecorded part, that is, between songs), the timer 35 and the flip-flop 38 are set, and the timer 35 performs a predetermined clock signal division cycle. As a result, a branch signal as shown in FIG. 4(d) is output. A flip-flop 38 latches the output of the timer 35 (unlatching is performed by the output of the comparator 33) and outputs a latch signal as shown in FIG. The output signal of flip-flop 38 resets timer 36 and flip-flop 39. That is, the timer 36.

When the output Q of the flip-flop 39 reaches rHJ, it is reset, and from the "L" state, a predetermined branch signal of the clock signal as shown in FIG. 4 is output. do. The flip-flop 39 latches the output of the timer 36, and from the output Q, the signal shown in FIG.
An output signal such as σ) is output from the output Q as shown in Fig. 4 (
An output signal like A) is output. That is, while the output Q of the flip-flop 39 is rHJ, it corresponds to the song being played.

In rLJ, the pauses correspond to the gaps between songs, and the output d is the opposite. The output Q of the slip flop 39 is converted by a differentiating circuit 41 into a one-shot signal as shown in FIG.
(1) It is converted into a one-shot signal as shown. Therefore, the differentiating circuit 41. The output signal of the differential circuit 42 corresponds to the end of the song, and the output signal of the differentiating circuit 42 corresponds to the start of the song.

According to the output Q of the above flip-flop 39,
The timer 37 and the flip-flop 40 are reset. In other words, the timer 37 is reset when the flip-flop 3
When the output Q of 9 becomes rHJ, it is reset and becomes “L”.
From this state, a branch signal as shown in FIG. 4() is outputted by dividing the clock signal by a predetermined frequency. Flip flop 40.

The output of the timer 37 is latched, and an output signal as shown in FIG. 4(j) is outputted from the output Q. That is.

The output Q of the flip-flop 40 is from rLJ to rH
The point in time when it changes to J means that the nine-track blank has continued for a period of π. The output Q of the slip flop 40 is converted by a differentiating circuit 43 into a shot signal as shown in FIG. Therefore, the output signal of the differentiating circuit 43 means that the blank period for one song has continued for a predetermined period of time. Furthermore, the differentiation circuit 41
The output signals of 43 to 43 are output from AND circuits 44 to 4 controlled by the mode signal input to the MSF terminal 48.
6 and output from output terminals 55 to 57, respectively. In addition, the above mode signal is "H" in the single head detection mode.
”, shall be rLJ in play mode. Now, assuming that the mode signal is switched to the cue detection mode at T1 during one song as shown in FIG. 4(n), AND circuits 44 and 45 are in an open state. Since the υ AND circuit 46 is in a closed state, the pulse signal (shown in FIG. 4(k)) indicating the end of the song output from the differentiating circuit 41 at T2 is as follows.

The signal passes through the AND circuit 44 and is output from the output terminal 55 as shown in FIG. 4(o). The output terminal 5
Pulse signal output from 5 (signal indicating the end of the song)
If the mode signal (n) is inverted and becomes rLJ,
The AND circuits 44 and 45 are in a closed state, and the SAND circuit 46 is in an open state. Therefore, at T4, the pulse signal output from the differentiating circuit 42 (Fig. 4 (
g) as shown) nor the pulse signal outputted from the differentiating circuit 41 at T5 (shown in FIG. 4(k)) cannot pass through the AND circuits 45 and 44. That is, the end of a song and the start of a song detected in the play mode are ignored. However, the pulse signal outputted from the differentiating circuit 43 (shown in FIG. 4(B)) at T7, where the blank state continues for a predetermined period of time after the end of the 9th song, is as shown in FIG. 4(S). It is output from the output terminal 57 via the circuit 46. The signal outputted from the output terminal 57 is a blank skip signal according to the present invention. and.

The blank skip signal causes the tape writing mode to be switched to cue detection mode.

The mode signal (J is inverted to rHJ. Therefore, Ts
The pulse signal (shown in FIG. 4(1)) outputted from the differentiating circuit 42 is transmitted from the output terminal 56 as shown in FIG.
The output is as shown in the figure.

Even if the mode signal is switched to the cue detection mode at T3 and T6, which are between one song, as shown in FIG.

The signals output from the output terminals 55 to 57 are as follows.

As shown in FIG.

As explained above, according to the present invention, no matter what timing the cueing detection mode is switched to.

Instead of detecting all song start states that appear after that, a blank skip signal is output when an unrecorded section continues for a predetermined period of time, making it possible to perform effective song selection operations. becomes. Additionally, since external components require fewer parts, it can contribute to cost reduction.

[Brief explanation of drawings]

Figure 1 shows the configuration of a conventional example of a tape cue selection circuit device;
The figures are a timing chart for explaining the operation of the conventional example shown in FIG. 1, FIG. 3 is a timing chart for explaining the configuration of an embodiment of the present invention, and FIG. Show chart. In the figure, 31 is an input terminal, and 32 is an inverting operational amplifier. 33 is a comparator, 34 is a clock oscillator, 35 to 37
is a timer, 38 and 4o are flip-flops, 41
Tanning 43 is a differential circuit, 44 to 46 are AND circuits,
47 represents an inverter, 48 represents an MSF terminal, and 49 represents an analog switch. Patent applicant Alpine Co., Ltd.

Claims (1)

[Claims] A music selection circuit device in a tape deck that detects the beginning of a song recorded on a tape includes an operational amplifier for amplifying an audio signal, and a comparison process for the output of the operational amplifier. Let's go comparator. A clock oscillator that outputs a clock signal, detects the end of the song recorded on the tape based on the clock signal from the clock oscillator and the output of the comparator, and detects when a predetermined time has elapsed from the end of the song. A first timer that outputs a frequency-divided signal, a second timer that detects the start time between songs and outputs a division signal when a predetermined time elapses from the start time of the song, and a non-recording state for a predetermined period of time from the end of the song. A third timer that outputs a frequency division signal at a continuous time point, and first to third flip-flops that independently latch the division signals of the first to third timers, respectively, The 9th song end signal is based on the output of the flip-flop No. 3 and the mode signal corresponding to the cue detection mode and play mode. 1. A song selection circuit device for a tape deck, characterized in that it is configured to output a song start signal and a blank skip signal indicating that a non-recording state has continued for a predetermined period of time from the end of a song.