JP3187466B2 - Electronic musical instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic musical instrument, and more particularly to an electronic musical instrument capable of generating musical tones only with a single tone.

[0002]

2. Description of the Related Art Conventionally, various electronic musical instrument devices have been proposed. The signal (key press signal) indicating that the operation switch) has been pressed
This is performed by the CPU of the microcomputer scanning each key switch.

When a microcomputer is provided in this manner, the electronic musical instrument can be provided with various additional functions.

When a plurality of musical tones are output simultaneously (in the case of a chord output), for example, a volume switch for volume control is operated too much, and a signal to be input to an amplifier connected to a speaker becomes excessive. Then, the amplifier saturates and cross-modulation occurs in the output signal of the amplifier,
The tone generated from the speaker is muddy or broken.

On the other hand, in the case of a single tone output, even if the signal to be input to the amplifier becomes excessive and the amplifier is saturated, the output signal of the amplifier only distorts its waveform, so that the tone changes. Although sound may occur, the sound does not become muddy or broken. In the case of single-tone output, complicated performance cannot be performed, but it is suitable as an electronic musical instrument handled by children and beginners.

[0006]

When an electronic musical instrument device capable of outputting only a single sound is to be constructed, as described above, the user of the electronic musical instrument device is mainly a child or a beginner in many cases. Therefore, in such a case, the electronic musical instrument device only needs to have a function of playing the musical instrument purely, and often does not require much additional function.
Therefore, a relatively simple configuration should be sufficient.

However, when a microcomputer is used to generate a key press signal, the configuration of the electronic musical instrument becomes complicated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an electronic musical instrument device capable of outputting only a single sound without using a microcomputer, and with a simple configuration without using a microcomputer. To provide an electronic musical instrument device capable of generating the following.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an electronic musical instrument apparatus for generating a musical tone by a single tone, comprising: an on / off determining means to which a plurality of key switches are connected; A pulse generator that generates a pulse in synchronization with the on / off information of each key switch serially output from the on / off determining means after the on / off determining means captures the on / off information of each key switch. And an OR gate for calculating the logical sum of the on / off determining means and the pulse generator.

In addition, the present invention further comprises a first integration circuit that receives the pressed state information, which is the output signal of the OR gate, as an input signal, and sets the time constant of the first integration circuit so that when a wide key pressing signal is input, Another feature is that the output of the first integration circuit is set to exceed the first predetermined level Vset.

[0011]

According to the present invention, a pulse is generated from the on / off determining means at a timing corresponding to a pressed key, and this pulse is added to an output pulse of the pulse generator. Therefore,
The width of the key press signal is wider than that of the non-key press signal.

Further, when the first integration circuit is provided, the output of the first integration circuit exceeds the first predetermined level Vset when the key depression signal is inputted. A determination can be made.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings. 2 and 3 are circuit diagrams showing the configuration of an embodiment of the present invention. FIG. 2 shows a keyboard 1 having key switches 1-1 to 1-N and depression of key switches 1-1 to 1-N. FIG. 3 is a circuit diagram of the operation unit 101 including a key press signal (pitch signal) generator that generates a state as an electric signal. FIG. 3 shows a frequency signal generator that generates a signal having a frequency corresponding to the key press signal, and the frequency signal. (Amplifier) 44 and speaker 45 for amplifying
FIG. 3 is a circuit diagram of a musical tone generating unit 102 including a battery and a battery 56.

In each of the drawings, terminals L1 and L2 and terminals M1 and M2 are provided in an operation section 101 and a tone generation section 102, respectively, and are connected to each other through a pair of connection lines (not shown). L1 is connected to terminal M1, and terminal L2 is connected to terminal M2. Then, a key press signal is transmitted from the operation unit 101 to the musical sound generation unit 102, and the power from the battery 56 is transmitted from the musical sound generation unit 102 to the operation unit 101.
Supplied to

The operation of this embodiment will be described in detail with reference to the time chart of FIG. First, in FIG. 3, the battery 56 provided in the musical sound generator 102 is connected to the terminal M1 via the power supply circuit 20 having the resistor 23.

Next, in FIG. 2, a predetermined potential Vcc is generated at a connection point of the diode 12 and the capacitor (capacitor means) 13 as will be described later, and this Vcc is applied to the operation unit 101.
It is used as the power supply voltage.

The pulse generator 5 generates a pulse with the same cycle as the clock pulse generated by the clock generator 3 and outputs the pulse to one terminal of the OR gate 6 (FIG. 4).
A).

Shift register (on / off determining means) 4
Is a parallel-in / serial-out format, and one end of N key switches 1-1 to 1-N corresponding to the N keys of the keyboard 1 is connected to the input terminal of each stage. The shift register 4 may be, for example, a 4014 type shift register or a plurality of such shift registers connected in series.

The other ends of the key switches 1-1 to 1-N are commonly connected, and are supplied with a power supply voltage Vcc via a resistor 2. These key switches 1-1 to 1-N
Is always off, but is turned on by pressing a key (not shown).

The frequency divider 7 has a cycle T having a half cycle of (N + n) clock pulses (n is a positive integer), and has one input terminal of an AND gate (data superimposing means) 8 and a shift register 4. A square wave is output to the control terminal 4A (FIG. 4D). The shift register 4 simultaneously (parallel) signals indicating the on / off states of the key switches 1-1 to 1-N at the time of the rise of the "H" signal of the square wave. Take in. Thereafter, the shift register 4 sequentially (serially) outputs a signal indicating the on / off state to the other terminal of the OR gate 6 in synchronization with the input clock pulse. FIG. 4B shows an output signal of the shift register 4.

Since the pulse output from the pulse generator 5 when the frequency divider 7 rises to "H" corresponds to the key of the highest tone or the lowest tone of the keyboard 1, the pulse of the shift register 4 The output pulse is output at a position (timing) corresponding to the depressed key from the highest key or the lowest key. In the illustrated example, the position of the depressed key is the third key from the highest key or the lowest key.

As a result, the output of the OR gate 6 is
As shown in (C), the pulse width at the position corresponding to the pressed key is increased. The output of the OR gate 6 is output to the other input terminal of the AND gate 8. Therefore, the output of the AND gate 8 is as shown in FIG.

The output of the AND gate 8 is supplied to the base of a transistor (first switching means) 11 through a resistor 9, so that the transistor 11 also performs on / off operation as in FIG. As described above, since the terminal L1 is connected to the terminal M1 of the tone generator 102, the on / off of the transistor 11 causes the collector voltage of the transistor 11 to change as shown in FIG. An inverted waveform of (E) is obtained.

When the transistor 11 is off and its collector voltage is "H", the capacitor 13 is charged via the diode 12. As described above, when the output of the frequency divider 7 is "L", the collector potential of the transistor 11 continuously becomes "H", and when the output of the frequency divider 7 is "H", The potential is “H”
And "L" are repeated, the charging voltage Vcc of the capacitor 13 can maintain substantially the same value, and can be used as the power supply voltage of the operation unit 101.

Next, in FIG. 3, first, the collector of the transistor (second switching means) 22 is connected to a resistor 24.
Is connected to the battery 56. The terminal M1
Is the same as that in FIG. 4F, and when the potential is “H”, the transistor 22 is turned on. Therefore,
The change in the collector potential of the transistor 22 is shown in FIG.
As shown in FIG. This "H" pulse of the collector potential is input to the counter 25,
The number is counted. Further, the collector potential is input to the first integration circuit 26.

As described above, at the collector of the transistor 22, since the pulse width of the portion corresponding to the pressed key is large, the output voltage of the first integration circuit 26 is determined by the time constant shown in FIG. As shown in (1), it becomes higher in a portion where the pulse width is large.

The output voltage of the first integration circuit 26 is input to a set input terminal S of a flip-flop (hereinafter referred to as "F / F") 27. Here, the threshold value (first scheduled level) Vset (see FIG. 4 (H)) of the set input terminal S is determined by the pulse (non-depressed signal) corresponding to the key not depressed. (1) When a pulse (key press signal) that is larger than the output voltage of the integration circuit 26 and that is wider than the above-mentioned pulse corresponding to the pressed key is input.
Since the output voltage of the integration circuit 26 is set to be smaller than the output voltage, the F / F 27 is set when the wide pulse is input to the first integration circuit 26.

As a result, the output Q of the F / F 27 becomes "H".
(See FIG. 4 (L)), the pulse generator 28 generates a predetermined trigger pulse (see FIG. 4 (N)), and the latch 29 latches the count value of the counter 25. As a result, the latch 29 latches the number of keys from the highest or lowest key to the pressed key (hereinafter, referred to as “key number”).

A plurality of key numbers and frequency division ratio data corresponding to the key numbers are stored in the code converter 30 in association with each other in advance, and according to the key numbers output from the latch 29, The frequency division ratio data is output to the programmable frequency divider 31.

The programmable frequency divider 31 divides the frequency of the clock pulse generated by the clock generator 32 using the input frequency division ratio data, and outputs the input data, that is, the pulse of the frequency corresponding to the pressed key. The signal is output to the tone setting device 33.

The timbre setting device 33 is configured to generate four types of timbres in this example, and more specifically includes a frequency divider 51 and four AND gates 52 to 55. The frequency divider 51 has an output terminal 51A that outputs the input frequency signal as it is without dividing the frequency, and output terminals 51B to 51D that divide the input frequency signal by 、, ４ and １ ／ and output the divided signal. It has. The output terminals 51A and 51D are connected to a logic circuit using AND gates 52 to 55 as shown. The output of the tone setting device 33 is connected to a changeover switch 34. FIG. 5 shows the output waveform of each part of the tone color setting device 33.

The changeover switch 34 is used for changing the tone color.
5 is output to the base.

The collector potential of the transistor 22 is also input to the second integration circuit 36. The time constant of the second integration circuit 36 is set to be larger than that of the first integration circuit 26, and as a result, the second integration circuit 36
Is as shown in FIG. 4 (I). The time constant of the second integration circuit 36 is such that the output of the second integration circuit 36 becomes the second predetermined level Vrese after the output of the frequency divider 7 becomes “L”.
It is set to be less than t.

The gate 37 outputs the output of the second integration circuit 36 to its threshold (second predetermined level) Vreset (FIG. 4).
(See (I)) to output an “H” signal when the signal is below the threshold (see FIG. 4J). Accordingly, the output of the capacitor 38 connected to the output line of the gate 37 is as shown in FIG.

The output of the capacitor 38 is
5 is input to the reset terminal 25R.
The counter 25 is reset by the output, and is also input to the reset input terminal R of the F / F 27. Similarly, the F / F 27 is reset by the "H" signal.

When the F / F 27 is reset, its output Q
(FIG. 4L) becomes "L" and the output notQ becomes "H".
(FIG. 4M). With the rise of notQ to “H”, the retrigable multi 39 is energized, and the cycle T of the output pulse of the frequency divider 7 (FIG. 2) (see FIG. 4D, ie, the pulse generator 5 The pulse is output to the third integration circuit 40 for a time slightly longer than (the time for outputting (N + n) pulses) (FIG. 40).

The notQ does not rise to "H" unless the output of the first integration circuit 26 (FIG. 4H) exceeds the threshold value Vset and the F / F 27 is set. Therefore, the retriggerable multi 39 generates a pulse after a key is pressed. Further, since this pulse is generated in a cycle longer than the cycle T of the output pulse of the frequency divider 7 as described above, if the key is kept depressed, the retrigable multi 39 stops outputting the pulse. Will be re-energized. Therefore, when the key is depressed, the output pulse of the retrigable multi 39 also lasts for almost the duration.

The output pulse of the retrigable multi 39 is input to the third integration circuit 40. Since the third integration circuit 40 has a predetermined time constant, its output waveform is as shown in FIG.

The output of the third integrating circuit 40 is applied to the collector of the transistor 35 via the resistor 41. Therefore, the collector potential is as shown in FIG.
The collector potential of the transistor 35 is supplied to the amplifier 4 via a diode 42 and a variable resistor 43 for controlling the volume.
4 to drive the speaker 45.
As shown in FIG. 4 (P), since the third integration circuit 40 has a time constant, a musical tone is generated from the speaker 45 gently, and this musical tone gradually disappears.

In the above embodiment, the operation section 101 and the tone generation section 102 are separated from each other, and they are connected to each other using a pair of connection lines.
They may be integrated. In this case, the transistors 11 and 22, the diode 12, the capacitor 13, and the like may be omitted, and the output of the AND gate 8 may be connected to a position corresponding to the collector of the transistor 22. The power supply voltage Vcc of the operation unit 101 is directly supplied from the battery 56.

FIG. 1 shows a simplified configuration diagram of the above embodiment.
Shown in In FIG. 1, the same reference numerals as those in FIGS.
The same or equivalent parts are shown, and the switching means 35A corresponds to the transistor 35 in FIG.

As is clear from the description of FIGS. 2 and 3,
Parallel-in / serial-out shift register 4
Is ORed with the output of the pulse generator 5 so that the pulse width of the key press signal is wider than that of the non-key press signal. That is, a key press signal is generated.

When the wide key press signal is input to the first integration circuit 26, the output of the first integration circuit 26 exceeds Vset (that is, the key press signal is detected).
As a result, the F / F 27 is set, and the count value of the counter 25, that is, the key number is latched by the latch 29.

When a plurality of keys are depressed almost simultaneously, the frequency divider 7
During the "H" output period (FIG. 4D), if a plurality of wide key press signals are output from the AND gate 8, the F / F 27
Is set by the first pulse (the highest or lowest key of the pressed keys) output from the AND gate 8 of the plurality of key pressing signals, and the key number corresponding to the pulse is latched. 29 is latched. Here, F / F2
7 is not reset unless the output of the frequency divider 7 becomes “L” (see FIGS. 4I to 4M), even if there are a plurality of key presses during the “H” output period of the frequency divider 7, During the output period T of the frequency divider 7, only the key tone corresponding to the first wide pulse output from the pressed state detecting means 302 is output from the speaker 4.
5 is not output.

In the above description, on / off determination of each key switch is performed using the shift register 4. However, if the output can be output serially, a ring counter or the like can be used. (On / off determining means) may be used.

Also, the present invention basically performs the logical OR operation of the serial output of the on / off determining means and the output of the pulse generator 5 so that the pulse width of the key press signal is not depressed. The width of the key signal is made wider than that of the key signal, thereby generating a key press signal. Further, the key press signal is detected by using the first integration circuit 26. Therefore,
Other configurations may be arbitrary.

In the above description, the period T of the frequency divider 7 is twice the value obtained by adding a positive integer n to the number N of keys of the keyboard 1, but n is 0. May be.

Further, the retriggerable multi 39 shown in FIG. 3 is started at the rise of the output notQ of the F / F 27.
If the timing at which the frequency signal is output to the base of the fifth and the timing at which the output signal of the third integration circuit 40 is applied to the collector of the transistor 35 match, the retrigable multi 39 outputs the output of the F / F 27. It may be triggered by the rising edge of Q or another signal.

Further, the electronic musical instrument has been described as having a keyboard having a key switch 301.
The key switch 301 is not limited to a key switch of a keyboard, and may be, for example, a valve switch of a wind instrument, various operation switches of a stringed instrument or a percussion instrument.

[0050]

As is clear from the above description, according to the present invention, the following effects are achieved.

(1) According to the electronic musical instrument of the first aspect, the width of the key pressing signal is wider than that of the non-key pressing signal. That is, a key press signal can be generated with a simple circuit configuration without using a CPU.

(2) According to the electronic musical instrument of the second aspect, the wide key press signal generated as described above can be detected only by providing an integrating circuit. That is, C
A key press signal can be detected with a simple circuit configuration without using a PU.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of one embodiment of the present invention.

FIG. 2 shows a key switch 1-1 according to an embodiment of the present invention.
Key 1 having keys 1 to 1-N and key switches 1-1 to 1-N
FIG. 4 is a circuit diagram of an operation unit 101 including a key press signal generator that generates a press state of the key as an electric signal.

FIG. 3 is a diagram showing a tone signal including a frequency signal generator for generating a signal having a frequency corresponding to a key press signal, an amplifier 44 and a speaker 45 for amplifying the frequency signal, and a battery 56; FIG. 3 is a circuit diagram of a generator 102.

FIG. 4 is a time chart showing the operation of FIGS. 2 and 3;

5 is a time chart showing the operation of each part of the tone color setting device 33. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Keyboard, 1-1 to 1-N ... Key switch, 4 ... Shift register, 5 ... Pulse generator, 6 ... OR gate, 7 ... Divider, 8 ... AND gate, 25 ... Counter, 26 ... 1st integration Circuit, 27 F / F, 29 Latch, 30 Code converter, 31 Programmable frequency divider, 35A Switching means, 36 Second integration circuit, 37 Gate, 39
Retriggerable multi, 40 ... third integrating circuit, 43 ... variable resistor, 44 ... amplifier, 45 ... speaker, 101 ... operating unit, 102 ... music generating unit

Claims (2)

(57) [Claims] 1. An electronic musical instrument device for generating a musical tone with a single tone, wherein a plurality of key switches are connected, an on / off state of the key switches is periodically detected, and the on / off information is serially output. An on / off determining means for performing the operation; a pulse generator for generating a pulse in synchronization with the output of the on / off determining means; and a logical sum of the outputs of the on / off determining means and the pulse generator. An electronic musical instrument apparatus comprising: an OR gate that outputs pressed state information including a non-key pressed signal having a pulse width and a key pressed signal wider than the pulse width. 2. A method according to claim 1, wherein said pressing state information is an input signal.
An integration circuit, wherein the time constant of the first integration circuit is such that when a wide key pressing signal included in the input pressing state information is input, the first constant
The output of the integration circuit is set to exceed a first predetermined level Vset, and when the output of the first integration circuit exceeds the first predetermined level Vset, a detection determination of a key press signal is performed. Item 3. The electronic musical instrument device according to Item 1.