JPS6029118B2 - automatic accompaniment device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic accompaniment device that generates an autochord accompaniment pitch name designation signal corresponding to a chord name designated by an accompaniment keyboard, and forms an automatic chord accompaniment tone using this signal. It is something.

In an automatic accompaniment device, it is necessary to detect the root note and chord type of the chord formed by the pressed keys, and generate a note name designation signal (ACC signal) for performing automatic chord accompaniment based on this information. be. However, since there are a large number of combinations of root notes and chord types, the degree of complexity of the circuit configuration varies greatly depending on the ACC signal generation method used. The object of the present invention is to provide a frequency signal generation circuit and an R for storing frequency names corresponding to chord types.
The object of the present invention is to provide an automatic accompaniment device that can obtain an ACC signal with a simplified circuit configuration by exploring a completely different configuration from the conventional one by combining an OM (read-only memory, hereinafter the same).

The present invention will be explained in detail below based on the drawings.

FIG. 1 is a block diagram of an embodiment of an automatic accompaniment device according to the present invention, and the device is constructed by connecting an automatic accompaniment circuit 1 to external circuits. The details of the automatic accompaniment circuit 1 are as shown in FIG. The outline of the device will be explained first. First, the automatic accompaniment circuit 1 is supplied with a clock pulse CLK (see FIG. 4) from the clock pulse generation circuit 2. Then, timing signals T, , T2, . . . , T, 3 are generated at terminals t2, . They are respectively supplied to the accompaniment key circuit 4. The foot key circuit 3 has 13 foot keyboard on/off switches for specifying bass note names, and the foot key note names are assigned to the timing signals as shown in Table 1. Table 1 Also, the accompaniment key circuit 4 has an on/off switch on the accompaniment keyboard that specifies a chord (chord) for automatic accompaniment, and the note names of the accompaniment keys are assigned to the timing signals in Table 2. ing.

Table 2 The timing signals T, , L, . . . specified by the foot key circuit 3 and accompaniment key circuit 4 are OR circuit 5,
6 are combined into one control line and led to the ik terminal and ip terminal of the automatic accompaniment circuit 1, respectively.

The code detection result of the accompaniment key designation signal lx to the ik terminal is
A binary signal (code type designation signal) as shown in Table 3-1 is taken out from each terminal of ch-1, ch-2, and ch-3. Accompaniment key designation signal IK for C chord
Table 3-2 shows an example of the percentage of code types. Third
Table 3-1 Here, the symbol 1 indicates the key-pressed state, and the blank indicates the key-released state.

Further, in the case of an accompaniment key designation signal IK other than Table 3-2, it becomes a deliberate key ER. These chord type designation signals are supplied to the bass pattern designation circuit 7 and rhythm selection circuit 8'.
Along with the rhythm specification signal generated from the rhythm name (waltz, rumba, etc.) and chord type (major, minor, etc.)
Select the information to be stored. Then, in accordance with the timing signal generated by the rhythm pulse generation circuit 8, the stored information, that is, the 4-bit binary frequency signal specifying the bass pattern for automatic bass accompaniment is read out. An example of this is shown in the fourth
Shown in the table. Table 4 In addition, the bass pattern specifying circuit 7 also generates an attack signal ATK for switching to automatic bass accompaniment that automatically generates a bass tone corresponding to the chord.

4-bit frequency signals B, , B2 specifying the secondary tone of the auto bass sound sent from the bass pattern specifying circuit 7;
, B4, & and various control signals from the one-finger control circuit 9 used when playing the electronic organ in one-finger mode, and the octave control circuit 10.
control signals for octave control of the bass sound output from the multiplexers 11 are applied to the multiplexers 11, and the timing signals T,, L, . . .
. . , T, o, the signal is converted into a time-division signal, and applied to the ib terminal of the automatic accompaniment circuit 1 via one control line. Here, the frequency signals B, B2, &, B8 are 4-bit binary serial timing signals and are assigned as shown in Table 5. In addition, ib in Table 5 includes a signal for switching the auto bass tone from major to minor or major to seventh, which will be described later, and a signal for switching from major to minor or major to seventh for the auto chord note name designation signal ACC, which will also be described later. , and an octave signal is added.

From the side SS terminal of the automatic accompaniment circuit 1, a bass blue signal or an auto bass blue signal of the note name designated by the foot key designation signal IF is output.

To switch between the foot key bass sound signal and the auto bass sound signal,
This is done using the attack signal ATK. When the foot keys are given priority and there is no FOOT signal, the sound is switched to the auto bass sound as shown in FIG. 10, which is synchronized with the front green of the ATK signal. Furthermore, when a plurality of foot keys are pressed at the same time, the bass note having the note name of the lowest note is output. This auto bass tone is a pitch name output after adding the auto bass pitch name designating signal 18 applied to the ib terminal and the root note of the detection code, and performing hexadecimal correction.

Further, from the acc terminal of the automatic accompaniment circuit 1, an autochord pitch name designation signal ACC for autochord accompaniment is outputted as a serial timing signal. The truth table for the ACC signal is the sixth
As shown in Table-1, Table 6-2, and Table 6-3.
Table 6-1 shows major chords/mishit keys, Table 6-2 shows diminished chords, and Table 6-3 shows minor, seventh, and augmented chords. Code 1 indicates high level and blank indicates low level. be. In the case of the C major chord, FIG. 6 shows the relationship between the autochord pitch name designation signal ACC and the timing signals T, . . . , T, 3. Table 6-1 Table 6-2 Table 6-3 Such an autocode pitch name designation signal is supplied to the demultiplexer 12, where the timing code T, . . .
, T, 2 and are converted into parallel DC signals specifying 12 autocode tones (C, C#, . . . , B).

This parallel DC signal is sent to the chord tone generation circuit 13 to generate an autochord tone specified by the autochord tone name signal, but this autochord tone is generated by the rhythm pulse generation circuit 8.
The timing is determined by the rhythm timing signal sent from the automatic chord accompaniment tone. The rhythm timing of the signal BASS from the gunwale ss terminal is determined by the ATK signal sent from the base pattern designation circuit 7 in the timing gate circuit 14 . The memory switch circuit 15 is a circuit that controls the memory operation, that is, the operation that continues the automatic accompaniment even if the accompaniment key is released, and continues to output the specified bass tone even if the foot key is released. The control gate circuit 16 controls whether the KEY signal sent from the ke terminal is passed or not. This KEY signal is a serial timing signal circle, , T that indicates whether the accompaniment key and the foot key are in the pressed or released state. Reference numeral 17 denotes a demultiplexer, which forms the tones of the chord blue signal and the BASS signal in the tone name synthesis circuit 18, and
It is supplied to the amplifier 20' together with the rhythm signal No. 9, and drives the speaker 21. Next, how output signals corresponding to the input signals are formed and output based on various input signals supplied to the automatic accompaniment circuit 1 will be explained with reference to the circuit diagram shown in FIG.

The clock signal from the clock pulse generation circuit 2 described above is transmitted to various timing signals T3, T5,
T3 14 10 5'75 10...10↑8(
(See Figure 4) is converted by the timing signal generation circuit 3.
0, these timing signals are supplied to various circuits.
The accompaniment key designation signal lk is provided by the timing pulse waveform shaping circuit 3.
1, the waveform is shaped and sent to the code detection circuit 32, and as mentioned above, the 3-bit binary code signals CH1, C
Consider H2 and CH3. This code detection circuit 32 is
For example, it consists of a combination of a shift register and a ROM, in which a serial timing signal corresponding to the note name pressed is input into the shift register, shifted sequentially and compared with the contents of the ROM, and detection is performed when a match is detected. be. However, this is just an example, and code detection is also performed from subordinates, so there is no harm in using it as is. The code signal obtained in this way is sent to the code storage circuit 37 and stored therein, and
The code detection circuit 32 outputs the code Atsushi pulse signal AC.
RD is generated and sent to the chord/root note writing pulse generation circuit 33, and an ALL-OFF signal that detects that none of the accompaniment keys are pressed is sent to the accompaniment key ALL-OFF signal generation circuit 34. Send. A key change detection circuit 35 detects a change in the pressing of an accompaniment key, and its output controls a waiting time generation circuit 36, which generates a chord/root note writing pulse for a certain period of time when the accompaniment key is turned on or off. circuit 3
3 is stopped to prevent malfunction of code detection.
The code signals CHI, CH2, CH3 are directly output from the code terminals, and are decoded by the decoder 38 into code type signals (major (M), minor (m), . . . ) and a keystroke signal ER.

Then, in the ACC-m and hole h control circuit 39, the m
(Maina), converted to Earth (Sepunsu). However, A
When the CC-m and ACC-7th control signals are not applied, the output of the decoder 38 is directly supplied to the ACC signal generating circuit 4. Further, a chord/root note write pulse ACD-P signal having the same timing as the root note timing from the chord/root note write pulse generation circuit 33 is also supplied to the ACC signal generation circuit 401. ACC signal generation circuit 40
A specific example of this is shown in FIG. 3, and includes a frequency signal generation circuit 65 and a ROM 66.

The frequency signal generation circuit 65 has four toggle flip-flops 67a, 67b, 67c, and 67d that are continuously maintained.
A counter circuit that performs a forward operation, an OR circuit 68 whose output is connected to the reset terminal R of the counter circuit, an AND circuit 69 whose output is connected to the T terminal of the first stage toggle flip-flop 67a, and a set-reset flip-flop. Flop 7
has 0. The R terminal of the set-reset flip-flop 70 and the AND circuit 69 are supplied with timing pulses 750 to 78, which are the same as those supplied to the pitch name signal generator 51, which will be described later. The inverted timing signal To, 2 is applied to the gate terminal, and the chord/root note writing pulse generation circuit 3 is applied to the OR circuit 68.
The write pulse signal ACD-P from 3 and the output signal of the set/reset flip-flop 70 are supplied. Therefore, the frequency signal generation circuit 65 is reset at the timing of the root note, and the internal state of the counter circuit is sequentially changed at the same timing as the operation timing of the note name signal generator 51, and each toggle flip-flop is reset.

From the Q terminals on the output side of 67a, ..., 67d, frequency signals n, , n2, peaks, and n8 of binary words are obtained (11th
(see figure).

Next, the ROM 66 includes a first ROM part 66a that stores the frequency name corresponding to the chord type, and a second ROM part 66b that is connected to the first ROM part and decodes the frequency signal into a signal with a timing corresponding to the frequency name. has.

The frequency signals n, , n2, peaks, n8 and their inverted signals are stored in the ROM line 71a of the second ROM portion 66b.
, 7 1b, . . . , 7 1h, and the code signals M, m, ground, .
. . . is the R○M line 72a, 7 of the first ROM 66a.
2b,..., 72 days will be added. 1st RO
Table 7 shows the selection of the frequency name ROM line for the designated code type of M66a.

Table 7 Note that the 0 mark indicates selection of a ROM line.

As can be seen from this Table 7, since keys that are accidentally hit are the same as major chords, the frequency name of the major chord is selected even in the case of a key that is hit incorrectly. The truth table for frequency names is shown in Table 8. Table 8 Next, the operation of the ACC signal generation circuit 40 will be explained in more detail using the operation timing chart of FIG.

Now, suppose that an A major chord is specified on the accompaniment keyboard. Then, the chord detection circuit 32 detects medium M as the chord type and pitch name A as the root note of the chord. Therefore, only the major signal M of the chord type designation signals is applied at "1" to the ACC signal generating circuit 401, and each ROM line of 1st, major 3rd, and perfect 5th is selected. Further, a write pulse ACD-P is applied from the chord/root note write pulse generation circuit 33 at the timings To and o corresponding to the note name A. Here, the timing to express pitch name A is T in Table 2, such as h and o.
This is because the timing waveform shaping circuit 31 shapes the waveform by delaying it by 1 bit. By the write pulse ACD-P applied at the timings To and o corresponding to such pitch name A, the four torgue flip relops 67a, ..., 67d
is reset, and the frequency signals n,, n2, ~, n8 become “0”.
”, “0”, “0”, “0”. As can be seen from Table 8, this state corresponds to once, and an ACC signal is generated. This ACC signal is generated at the timings To and o. Since it comes out, it represents the note name A. Next, 750... + D8
・Toggle flip-flop with L, 2 timing signal.
The contents of 67a, . . . , 67d change sequentially.

Since it is a major chord, when it is a major third degree name, that is, the frequency signal n,, peak, ~, n8 is "0", "0", "
1" and "0", the next ACC signal is generated, but since this signal is output at the timing of To2, it represents the note name C#. Similarly, when the degree name is a perfect fifth, that is, the degree signal n ,,n2, mountain, n8 is “1”, “1”, “
1'' and ``0'', the next ACC signal is generated, and this signal represents pitch name E since it is output at timing t5. In this way, To, o, L2, To5, To, o,...
A signal is generated at the serial timing of , and becomes an A major autochord note name designation signal. The process of creating an automatic chord accompaniment tone from such an ACC signal is as described above. Now, in FIG. 2, the foot key designation signal IP is shaped by a timing pulse waveform shaping circuit 41, and then is shaped by a foot key sound detection circuit 42.
Pitch name detection pulse PE that is supplied to detect the pitch name of the foot key.
At the same time as generating the D-P signal, a foot key press signal FOOT is generated, and the foot key press FOOT is output together with the ATK-P signal supplied from the ATK pulse generating circuit 44 to the foot key/auto base switching signal generating circuit 43. PEDAL that is supplied and switches between normal foot key performance and auto bass accompaniment.
Generate a signal.

When the ATK-P signal is applied when there is no foot key press signal sent from the foot key note name detection circuit 42, the accompaniment is switched to auto bass accompaniment. These are time-divided by the multiplexer 5011 timing signals To, , To2, and the PEDAL-ON signal indicating that the foot key is pressed and the MANU-ON signal indicating that the accompaniment key is pressed.
Output from the ke power terminal as a Y signal. Next, the pitch name signal generator 51 generates 12 pitch names CL, C#, . . . of the accompaniment keys.
・, 13 note names of B and foot keys CL, C#,...
, CH generate binary word pitch name signals N8, N4, N2, N as shown in Table 9. FIG. 7 shows a waveform diagram of the pitch name signal. Table 9 Pitch name signals representing each of these pitch names are processed by the decoder 52 as timing signals t,, L2, . . . corresponding to each pitch name.
. . , To, 3 (see FIG. 5).

That is, in this embodiment, the pitch name signal generator 51 and decoder 52 are combined to form a pitch name timing signal generation circuit that generates timing signals corresponding to each pitch name on the keyboard. The output of the decoder 51 is a waveform shaping circuit 53, which is a timing signal T, which is narrowed and widened by the timing signals 73, 174, 1, and 5.
T,3 (see FIG. 9) is outputted from the t, 3 terminal, and the external circuit is controlled in a time-division manner. Also, the S-CLK signal (seventh
(see figure) are supplied to the sequence signal generation circuit 54, and the sequence signals S, , S2, S
3, S4 (see FIG. 8) is generated. Furthermore, various control signals inputted from the ib terminal are converted from serial signals to parallel signals by a demultiplexer 55, and become various DC signals. Among these, 4-bit binary signal 18,
L, 12, 1, output is BASS-m, hh control circuit 5
When the BASS-m control signal is applied to BASS-6, the major third signal is converted to a minor third signal, and when the BASS-7th control signal is applied, the perfect fifth signal is converted to a minor seventh signal. These 4-bit binary frequency signals are supplied to an adder circuit 57 and added to the 4-bit binary root tone signal from an accompaniment key pitch name storage circuit 58 to perform scale correction. Here, the accompaniment key pitch name storage circuit 58 latches the 4-bit pitch name from the pitch name signal generator 51 at the timing of the ACD-P signal generated by the accompaniment key press signal IK, and stores the root note. It is something. In addition, the foot key/auto base cutting fusuma circuit 59
Then, the binary signal from the adder circuit 57 or the foot key note name storage circuit 60 is selected by the PEDAL signal and sent to the hexadecimal correction circuit 61.

This foot key pitch name memory circuit 60 also has four parts of the pitch name signal generator 51.
The pitch name of the bit is P created by the key press signal IP of the foot key.
It is latched by the ED-P signal and the root color is stored. In the thirteenth correction circuit 61, when the value added by the addition circuit 57 exceeds the digital value corresponding to the bass note name CH, the value is corrected to the digital value of the corresponding bass note name CH,
It also sends an OCTAVE signal that controls the octave of the bass sound to the octave switching circuit 62.

The 4-bit binary pitch name signals B, B, B4, & from the 13 base correction circuits 61 that specify the bass note name are converted by the decoder 63 into a DC signal that specifies the bass note name, and then
The bass note generation circuit 64 specifies the bass note name CL,
It generates bass sound signals of C#, . . . , CH, and outputs a bass blue signal BASS from the bass terminal via the octave switching circuit 62. In this way, automatic accompaniment is performed by the automatic accompaniment circuit and the peripheral circuits connected to it.

That is, in the automatic accompaniment device according to the present invention, a timing signal corresponding to each note name on the keyboard is generated, and the timing signal is applied to the chord detection circuit 32 as a key press signal to generate the root note and chord of the specified chord. Detect type and ACC
The signal generation circuit 40 uses the detection signal to generate a pitch name signal for automatic chord accompaniment. The ACC signal generation circuit 40 is reset at the timing of the detected root note, and a frequency signal generation circuit that sequentially generates frequency signals of binary words at the same timing as the timing signal corresponding to the note name; It has a first ROM part that stores a frequency name corresponding to the chord type, and a second ROM part that is connected to the first ROM part and decodes the frequency signal into a signal with a timing corresponding to the frequency name, The first ROM portion is read out using the code signal from the chord detection circuit 32, and a sequentially changing frequency signal is applied to the second ROM portion to obtain a pitch name designation signal ACC for white accompaniment with serial timing. This is how it is. Note that in the above embodiment, one octave (C,
C#, ..., B), so A
Although the counter circuit of the frequency signal generation circuit 65 of the CC signal generation circuit 40 operates in decimal notation, the present invention is not limited thereto.

As described above, in the present invention, the ACC signal generating circuit is constructed by combining the frequency signal generating circuit and the ROM, so that the circuit construction can be significantly simplified.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the automatic accompaniment device according to the present invention, FIG. 2 is a block diagram of the automatic accompaniment circuit of FIG. 1, and FIG. 3 is a circuit diagram of an embodiment of the ACC signal generation circuit. Fig. 4 is a timing chart of input/output signals of the timing signal generation circuit, Fig. 5 is a timing chart of input/output signals of the note name signal generator and decoder, and Fig. 6 is a diagram showing the relationship between the ACC signal and the timing signal. , Fig. 7 is a timing chart of input/output signals of the pitch name signal generator, Fig. 8 is a timing chart of output signals of the sequence signal generation circuit, and Fig. 9 is a timing chart of input/output signals of the pitch name signal generator.
The figure is the input/output timing chart of the waveform shaping circuit.
FIG. 0 is an explanatory diagram of the operation of the foot key/auto base switching signal generation circuit, and FIG. 11 is an operation timing chart of the ACC signal generation circuit. 1... Automatic accompaniment circuit, 32... Chord detection circuit, 4
0...ACC signal generation circuit, 51...
Pitch name signal generator, 52...decoder, 65...
...Frequency signal generation circuit, 66...ROM,
66a...first ROM part, 66b...
...Second ROM part. Figure 1 Figure 3 Figure N Rudder Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure Ship

Claims (1)

[Claims] 1. A pitch name timing signal generation circuit that generates a timing signal corresponding to each pitch name on the keyboard, and uses the timing signal as a key press signal to obtain the root note and chord type of the chord specified by the key press signal. The automatic accompaniment device equipped with a chord detection circuit as described above includes an ACC signal generation circuit that generates a note name signal for performing chord accompaniment in response to a detection signal of the chord detection circuit, the ACC signal generation circuit , a frequency signal generation circuit that is reset at the root note timing and sequentially generates frequency signals in binary words in synchronization with the timing signal, and a first ROM (read-only memory) that stores frequency names corresponding to chords. and a second ROM part that decodes the output signal of the first ROM part and the frequency signal output from the frequency signal generation circuit into a signal with a timing corresponding to the frequency name, and An automatic accompaniment device characterized in that the first ROM section is read out using a code signal, and a frequency signal that changes sequentially is applied to the second ROM section to obtain an ACC signal with serial timing.