JP2615880B2 - Chord detector - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chord detecting device that detects a chord based on a combination state of a plurality of pieces of pitch name information that respectively represent pitch names forming a scale.

[Prior Art] Conventionally, this type of device has a 12-bit shift register corresponding to a 12-tone scale as shown in, for example, JP-A-53-26115, and is designated by a simultaneous key depression operation on a keyboard. Data representing "1" is input to each bit position of the shift register corresponding to a plurality of pitch names, and the combination state of the parallel output of the shift register is changed to various chord types (measure, minor, seventh, etc.). A series of data in the shift register is cyclically shifted until one of the corresponding various combination states is matched.
Then, at the time when the combination states match, the chord type is determined according to the matched combination state, and the root of the chord is determined according to the number of cyclic shifts until the combination state. A chord corresponding to a key combination operation is detected.

[Problems to be Solved by the Invention] However, in the above-described conventional apparatus, a chord is determined by the coincidence detection of the first combination state after the start of the cyclic shift. If there is a chord to be detected, the other chords will be ignored. In such a case, there is no problem as long as the chord intended by the player is first detected as a match, but if the other chord is the one intended by the player, it is determined that an erroneous chord is detected. Become. In particular, when the number of types of chord types to be detected increases, or when the player performs a chord designation operation including a tension sound, the combination of a plurality of note names becomes complicated, and the frequency of the erroneous detection increases. Become. Furthermore, when the player makes a mistouch on the keyboard, the frequency becomes even greater.

When such a chord is erroneously detected, an automatic accompaniment sound such as an arpeggio sound or a bass sound formed according to the detected chord is not accurate, and the musicality of the automatic accompaniment sound deteriorates.

The present invention has been devised in view of such a problem, and an object of the present invention is to provide a chord detection device that accurately detects a chord according to a combination state of a plurality of designated note names.

[Means for Solving the Problems] In order to solve the above problems and achieve the object of the present invention,
The first invention (the invention according to claim 1) is characterized in that a chord detecting device for detecting a chord based on a combination state of a plurality of note name information respectively representing note names constituting a scale. Chord extracting means for extracting a plurality of detected chords by inputting pitch name information and detecting a chord in accordance with a combination state of a plurality of pitch names specified by the inputted respective note name information; and From the plurality of detected chords extracted by the extraction means, a detected chord that is a tension tone related to each detected chord and has a low degree of tension related to the tension sound included in the specified plurality of tone names is determined. And a chord determining means for determining the chord.

The second invention (the invention according to claim 2) is characterized in that the chord extracting means in the first invention is:
Root sound setting means for setting each of the plurality of specified sound names as root sounds; and for each root sound set by the root sound setting means, a sound name having a predetermined frequency relationship from the set root sound. And a judging means for judging whether or not it exists in a plurality of designated tone names.

The third invention (the invention according to claim 3) is characterized in that a basic constituent sound of a chord is previously defined for each of various chords as a note name having a predetermined frequency relationship in the second invention. I have to remember.

The fourth invention (the invention according to claim 4) is characterized in that the chord determining means in the first invention is characterized in that:
Means for determining, from among the plurality of detected chords extracted by the chord extracting means, a chord having a small number of tension sounds included in the designated plurality of tone names as a chord having a low degree of tension related to the tension sound; It consists in that.

Also, a structural feature of the fifth invention (the invention according to claim 5) is that the tension sound in the first or fourth invention is stored in advance for each of various chords.

The sixth aspect of the present invention (the invention according to the sixth aspect) is characterized in that the chord determining means in the first aspect comprises:
The plurality of detected chords extracted by the chord extracting means are configured to detect a chord including a tension tone having the lowest tension with respect to the detected chord as a chord having a low tension regarding the tension sound. .

Further, the seventh aspect of the invention (the invention according to the seventh aspect) is characterized in that the tension sound in the sixth aspect is stored in advance for each of various chords, and the degree of tension of each tension sound is represented by a numerical value. The advantage is that each chord is stored in advance.

[Operation of the Invention] In the first invention configured as described above, the chord extracting means once extracts a plurality of possible detected chords from a combination of a plurality of designated tone names, and determines a chord. The means finally decides one chord from the extracted plurality of detected chords in consideration of the tension sound included in each detected chord.

In such a case, the chord extracting device is configured, for example, as in the second and third inventions, and includes, among the plurality of designated tone names, note names having a predetermined frequency relationship from each of the root notes (stored in advance) The extraction operation is performed by determining whether or not the selected pitch name exists.

The chord determining means is configured, for example, as in the fourth to seventh aspects, and among the plurality of detected chords extracted by the chord extracting means, the chord having the least number of tension sounds (pre-stored). Is determined as a chord with a low tension related to a tension sound, or a chord including a tension sound with the lowest tension (pre-recorded) for the extracted chord among a plurality of detected chords extracted by the chord extracting means. The tension is determined as the chord with the lowest tension.

[Effects of the Invention] As can be understood from the above description of the operation, the first to seventh embodiments are described.
According to the invention, a plurality of possible detected chords are extracted, and finally a chord is determined in consideration of a tension sound belonging to each detected chord, so that the number of chord types that can be detected is increased. Even if the player performs a chord including a tension sound, the chord intended by the player is not ignored, and a musically accurate chord is detected. Then, based on such accurate chords, it is possible to generate an arpeggio sound, a bass sound, and the like of the automatic accompaniment appropriate for the musical piece.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing the entire electronic musical instrument according to the present invention.

This electronic musical instrument includes a keyboard 10, a key setting operation panel 20, a rhythm control operation panel 30, and an other operation panel 40. The keyboard 10 is composed of a plurality of keys for designating chords, and the depressed and released keys of each key are detected by opening and closing a plurality of key switches provided corresponding to each key in the key switch circuit 10a. Has become. Also, the key switch circuit 10a
Has a built-in chattering prevention circuit, a waiting time circuit, etc., which eliminates erroneous touches on the keyboard 10, detects multiple key presses with a slight time lag as simultaneous key presses, and It is detected as a key event. The key setting operation panel section 20 has a keyboard 10
Key setting selection operator that selectively switches between the auto mode in which the key is automatically set according to the chord performance of the keyboard and the manual mode in which the key is specified by a special key press operation on the keyboard 10.
21, a major operator 22 for designating a major key in the manual mode, and a minor operator 23 for designating a minor key in the manual mode. The operation in the key setting operation panel section 20 is detected by a key setting switch circuit 20a, and the circuit 20a includes a key setting selection switch 21a, a long key switch 22a and a key setting switch 22a corresponding to the operators 21 to 23, respectively. Built-in minor switch 23a. A rhythm control operation panel unit 30 includes a rhythm selection operator group 31 for selecting rhythm types such as blues, march, waltz, etc.,
A start / stop operator 32 for designating the start / stop of the rhythm, and operators 33 and 34 for designating the rhythm tempo, volume and the like are provided. These operators 31 to 34 are provided.
Are detected by a switch, a volume, and the like provided in the rhythm control switch circuit 30a. Other operation panel section 40 is provided with a large number of operation groups 41 and 42 for selectively controlling the tone color of the accompaniment sound, volume, and the like.Each operation of these operation group 41 and 42 is provided in the other switch circuit 40a. Detected by a switch, a volume, and the like provided.

These various switch circuits 10a to 40a are connected to a bus 50, and a percussion instrument sound signal generation circuit 61, an accompaniment sound signal generation circuit 62, a tempo oscillator 70, and a microcomputer 80 are connected to the bus 50.

The percussion instrument sound signal generation circuit 61 has a plurality of percussion instrument sound signal forming channels for forming instrument sound signals corresponding to percussion instruments such as cymbals and bass drums, and percussion instrument sound data PITD ₁ supplied from the microcomputer 80 via the bus 50. ~ PITD _m
A percussion instrument sound signal is formed and output according to. The accompaniment sound signal generating circuit 62 includes a plurality of (n-sequence) tone signal forming channels for forming musical instrument sound signals corresponding to musical instruments such as a piano and a violin.
In accordance with the tone data, tone data, key-on signal KON and key-off signal KOF, which are supplied via the bus 50, a tone signal having a tone corresponding to the tone data and a pitch corresponding to the tone data is formed and output. I do. These percussion instrument sound signal generation circuit 61 and accompaniment sound signal generation circuit 62 are an amplifier,
It is connected to a sound system 63 composed of a speaker or the like, and the system 63 emits a musical tone corresponding to the musical tone signal from both signal generating circuits 61 and 62.

The tempo oscillator 70 outputs a rhythm interrupt signal RINT having a predetermined frequency to the microcomputer 80,
The frequency of the signal RINT is determined according to tempo data supplied from the microcomputer 80 via the bus 50 in response to the operation of the tempo operator 33.

The microcomputer 80 includes a program memory 81, a CUP 82 and a working memory 83 connected to the bus 50, respectively. The program memory 81 is constituted by a ROM, and stores a main program corresponding to the flowcharts shown in FIGS. 5 to 12, a subprogram thereof, and a rhythm interruption program. The CPU 82 starts the execution of the main program when the power switch (not shown) is closed, and repeatedly executes the program until the power switch is opened, and outputs a rhythm interrupt signal RINT from the tempo oscillator 70.
, The execution of the main program is interrupted and the rhythm interrupt program is interrupted and executed. The working memory 83 is composed of a RAM, and has various registers and tables necessary for executing the program, as shown in FIGS. 2A to 2I. These registers and tables are as follows.

Key press buffer register 83a (FIG. 2A) has a storage area for the number of keys that are likely to be pressed at the same time, and stores all key codes KC representing keys pressed simultaneously to specify a chord. I do.

Key-depressed key flag buffer register 83b (FIG. 2B) Each recording area has a bit number corresponding to the 12th scale, and has a storage area for the number of keys that can be simultaneously depressed. "1" is the only note name that is the note name that corresponds to the key that was selected and that excludes clearly unnecessary note names (misnotes) from the chords (chords considered from key presses) that may have been specified by the player. A key depression flag is stored for each chord that may be specified.

Chord detection buffer register 83c (FIG. 2C) has storage areas for the number of keys that can be depressed, and for each storage area, the root of the chord considered from the key depression ROOT,
Same chord type TYPE, number of tension notes TENSU pressed for the same chord, lowest tension note number LTNO with lowest tension note number TNO among the pressed tension notes
And the chord tension level CTENL. Note that tension means tension, and tension sound is a basic constituent sound of a chord (for example, 1 ゜, 3 in the case of a minor 7 chord).
° ^♭, 5 °, the sound added to 7 ° ^♭ sound) (eg 9 °, is that the 11 ° sound). And in this case, the number of tension sounds
TENSU is the number of the additional sounds, and the tension sound number TNO represents the degree of tension of each additional sound, and the same number TNO is set so that the degree of dissonance of the chord increases as the number increases. (See FIGS. 3A and 3B). Further, the chord tension level CTENL represents the degree of tension of the chord itself, and the same level CTENL is set so that the chord that feels presence is a large value and the chord that can be heard with confidence is a small value. (See Figure 3C).

Rotation register 82d (Fig. 2D) This is a 12-bit register corresponding to the 12-note scale that stores a key-press flag in which only the note name corresponding to the key pressed simultaneously is "1". Each bit data is rotated.

Root counter 83e (FIG. 2D) Counts up in synchronization with the rotation of the rotation register 83d, and represents the key code KC of the root ROOT when a chord is detected.

Key-depressed key flag table 83f (FIG. 2E) The key-depressed flags stored in the key-depressed key flag buffer register 83b and relating to the chords used as detected chords for the past eight are stored.

Chord table 83g (Fig. 2F) Root ROOT and type of chords for the past eight chords corresponding to the key depression flags stored in key depression key flag table 83f
TYPE and chord tension level CTENL are stored.

Bruce table 83h (the 2G view) 12 scale by configured root note ROOT × 6 types of chords _{(I 7, IV 7, V} 7, I m7, IV m7, V m7) matrix storage area corresponding to the In each storage area, a flag indicating the presence of the corresponding chord by "1" is stored.

Tone flag table 83i (Fig. 2H) A chord ROOT composed of 12 scales, having a matrix-like storage area corresponding to four types of tones (blue major, minor and major and minor other than blues), and each memory "0" in the area
The number of determinations of each key that changes over the range from “3” to “3” is stored.

The other register 83j (FIG. 2I) temporarily stores the following variable data required for executing the program.

Performance start flag PSTF In order to detect the start of the performance, "0" indicates before the performance starts (before rhythm start) and "1" indicates after the performance starts.

Performance start minor flag PSTMF To be used for minor key detection, "1" indicates a chord minor chord or minor seventh chord at the start of performance,
And "0" indicates that the same chord is not the same.

Buffer Address BAAD This is address data for designating each storage area of the key press key flag buffer address 83b and the chord detection buffer register 83c.

Current table address CTAD This indicates a storage area for the latest chord in the key press key flag table 83f and the chord table 83g.
The AD value repeatedly specifies eight storage areas in a predetermined order.

Priority chord flag PCDF A flag indicating whether or not a chord has been preferentially determined according to a predetermined condition when one chord is determined from a plurality of chords stored in the chord detection buffer register 83c. Indicates that it has already been determined, and “0” indicates that it has not yet been determined.

Primary cadence chord flag PCCF A flag for allowing the primary chord or cadence chord to be selected as alternately as possible from a plurality of chords stored in the chord detection buffer register 83c,
“1” indicates that the cadence chord was previously selected,
“0” indicates that the primary chord was previously selected.

Key pressed chord data DPCHD This is a chord currently specified by the keyboard 10, and usually includes a root ROOT and a type TYPE.

First tension level sum SUMTENL1 Chord table for one key to determine key
Represents the total value of the past eight chord tension levels CTENL in 83g.

Second Tension Level Sum Value SUMTENL2 To determine the key, it represents the total value of the past eight chord tension levels CTENL in the chord table 83g for another key.

Temporary key data KMKD Before finalizing the key, it indicates the temporary key determined according to predetermined conditions.The most significant bit MSB indicates the length and the lower bit indicates the musical key key KC. Represents a key (C tone, G tone, etc.).

Key data MKD Represents the finally determined key, the most significant bit MSB
Represents the length, and the lower bits represent a musical key (C tone, G tone, etc.) by the key code KC.

Key setting flag MKSF This flag indicates whether the key has been set or not. “0” indicates before the key setting and “1” indicates after the key setting.

Modal data SCALE Represents the determined musical modality of the ionian, durian, etc.

Rhythm type data RHY Represents rhythm types such as march, waltz, etc. starting with blues.

Rhythm run flag RUN This flag indicates the operation state / stop state of the auto rhythm performance. “1” indicates the operation state, and “0” indicates the stop state.

Tempo count data TCNT This is count data indicating the progress of the auto rhythm, and repeatedly changes from "0" to "31" in correspondence with one or two measures.

Further, the bus 50 is connected to various detection tables 91, a rhythm pattern memory 92, and an accompaniment pattern memory 93. The various detection tables 91 are configured by a ROM,
Chord component sound table 91a, chord tension table 91b,
It has a primary / cadence chord table 91c, a first whirl table 91d and a second whirl table 91e.

The chord component sound table 91a has m7
_th , m7 _th ( ^♭ 5), 7 _th , Maj, SUS4 and other chords detected by the electronic musical instrument are compared with basic chord constituent tones shown in FIGS. 3A and 3B (for example, 1 ゜ for m7 _th ,
3 ^♭ , 5 ゜, 7 ゜^♭ sounds and tension sounds (for example, 9 ゜, 11 ゜ sounds for m7 _th ) are stored, and a tension sound number TNO (third sound) for the tension sound is stored.
A in the table in Figure A). Here, the notation of chords used in the present embodiment will be described briefly. However, the contents in parentheses [] indicate the case where the root ROOT is the C sound.

Major: Maj [C _Maj ] Minor: Min [C _Min ] 7th: 7th [C7th] Minor _7th : m7th [ _Cm7th ] Minor: 7th flat 5: m7th ( ^♭ 5) [ C _m7th
( ^♭ 5)] Suspendit 4 ··· SUS4 [C _SUS4 ] Seventh suspendpend 4 ··· 7th (SUS4) [C _7th
(SUS4)] Augment ... Aug [C _AUG ] Diminish ... Dim [C _DIM ] As shown in FIG. 3C, the chord tension table 91b stores chord data (C4) related to the various chords based on the C key. (In parentheses in the figure) are classified and stored in first to seventh groups, and the chord tension level CT is stored for each chord.
Remembers ENL. However, in FIG. 3C, a chord name (for example, I _Maj , III _m7th, etc.) in which each chord is represented in degrees and a chord group name (for example, primary chord, relayed II of secondary _dominite, etc.) of each group are shown. It is written.

As shown in FIG. 3D, the primary / cadence chord table 91c stores a primary chord group and a cadence chord group of frequency display for each group. Note that this frequency display corresponds to a chord name based on the C key, for example, _Im7th is _Cm7th
Corresponding to

As shown in FIG. 3E, the first melody table 91d is a table for examining a melody such as an ionian or a durian (see FIG. 3G) after the key is determined. It stores data representing the name of the modality. The second turning table 91e, as shown in FIG. 3F,
This is a table for determining a melody such as Ionian or Dorian before the key is determined, and stores data representing various melody names for each chord type TYPE such as Maj and Min.

The rhythm pattern memory 92 is divided into a plurality of putter memories for each rhythm type as shown in FIG. 4A, and each pattern memory stores tempo count data TCNT (0 to 31).
, And each address stores percussion instrument sound data PITD representing the number of percussion instruments to be pronounced, such as cymbals and bass drums. Further, data NOP indicating no processing is stored at an address which is not the sounding timing of the percussion instrument sound.

As shown in FIG. 4B, the accompaniment pattern memory 93 includes a plurality of series of accompaniment pattern memories 93-1, 93-2,... 93 corresponding to a plurality of accompaniment sounds such as arpeggio sounds and bass sounds.
-N. Each accompaniment pattern memory 93-1 and 93-2
.. 93-n are divided into a plurality of pattern memories for each rhythm type and each trajectory, and each pattern memory has 32 addresses specified by tempo count data TCNT (0 to 31). At each address, key-on data KON indicating the start of each accompaniment tone, pitch data PINT for determining the pitch of each accompaniment tone, and key-off data KOF indicating the end of each accompaniment tone (key-off) are stored. I have. In such a case, the pitch data PINT represents the notes on the scale related to each mode other than the avoidance sound as a semitone interval difference from the fundamental tone (root ROOT) of each mode. Data NOP indicating no processing is stored at an address that is not the sounding timing of each accompaniment sound.

Next, the operation of the electronic musical instrument configured as described above will be described with reference to FIGS. 5 to 12. Before describing the operation in detail, the overall operation of the electronic musical instrument will be schematically described. .

This electronic musical instrument ultimately determines the melody from the chord specified for key-depression, the determined key and rhythm type, and the accompaniment as appropriate as possible according to the harm-determination melody and the key-depression chord. The sound is determined and automatically generated according to the accompaniment sound rhythm.

Therefore, the key pressed chord needs to be determined as accurately and quickly as possible, and the chord is detected in different ways before and after the key is determined. That is, before the key is determined, the chord is determined to be the most likely without using information on the key, and after the key is determined, the chord is determined according to the determined key. The key is specified manually by the player or automatically determined to be the most likely according to the flow of the detected chord.
Then, in principle, the melody is determined according to the chord and key, and at the same time, accompaniment pattern data corresponding to the melody and rhythm are output, and an accompaniment tone corresponding to the pattern data and chord is obtained. Prior to key determination, accompaniment pattern data corresponding to the detected chord and rhythm type is output, and an accompaniment tone corresponding to the pattern data and chord is obtained.

Hereinafter, the detailed operation of the embodiment will be described in detail for each program and each routine.

Main Program The main program is as shown in the flowchart of FIG. 5. The execution of the main program is started in step 100 by turning on a power switch (not shown). In step 101, various variable data in the working memory 83 are initialized. Is set. After the initial setting, the CPU 82 continues to execute the circulation process including steps 102 to 129.

In step 102, it is determined whether or not there is a key pressing event associated with a key pressing operation on the keyboard 10. If there is no key pressing operation, “NO” is determined in step 102 and the program proceeds to step 118. If the key-pressing operation has been performed, “YES” is determined in step 102, all data in the key-depressing buffer register 83a is cleared in step 103, and the keys are simultaneously pressed in step 104. All the key codes KC relating to the keys are taken into the key press buffer register 83a from the key switch circuit 10a via the bus 50.

After the processing in step 104, it is determined in step 105 whether the key setting selection switch 21a is on the auto side. Now, if the key setting selection switch 21a is on the auto side in accordance with the operation of the key setting selection operation element 21, in step 105, "YE
Is determined to be "S", and a chord determination routine is executed in step 106. Although the details of this chord judgment routine will be described later, in this routine, a chord designated to be pressed on the keyboard 10 is detected. Next, at step 107, it is determined whether or not the performance start flag PSTF is "0". If the performance start flag PSTF is “0” and immediately after the start of the performance, based on the determination of “YES” in step 107, the chord determination routine is determined in step 108 by the processing of the chord determination routine and the key depression chord data DPCHD. Is determined, and if the current chord is the Min chord or the m7th chord, the performance start minor flag PSTMF is determined in step 109 based on the determination of “YES”.
Is set to “1”. Also, the current chord is Min chord or m7th
If it is not a chord, the performance start minor flag PSTMF remains "0" based on the determination of "NO" in the above determination. After the processing of these steps 108 and 109, the performance start flag PSTF is set to "1" indicating that the performance is not started at step 110, and the program proceeds to step 111. On the other hand, if the performance start flag PSTF at the time of the determination in step 107 is set to “1” indicating that the performance has started, the program proceeds directly to step 111 based on the determination of “NO” in step 107. Although the details of the key determination routine in step 111 will be described later, in this routine, the key is automatically determined based on the detected chord. Note that the processing of steps 107 to 110 is used to determine that the chord at the start of the music is a Min chord or an m7th chord, which is one of the conditions for detecting a minor key.

On the other hand, if the key setting selection switch 21a is on the manual side in accordance with the operation of the key setting selection operation element 21, the determination is "NO" in step 105, and the key switch 2 is determined in steps 112 and 113.
It is determined whether 2a or the minor switch 23a is on. The determination of the ON state of the major switch 22a or the minor switch 23a determines whether the key depression on the keyboard 10 is for key setting or for chord designation. Operation key switch 22a
In the ON state, the most significant bit of the key data MKD is determined in step 114 based on the determination of "YES" in step 112.
When the MSB is set to “1” indicating major,
The lower bit of KD is the key pressed on the keyboard 10 and is set to the key code KC for the highest tone key in the key press buffer register 83a. In addition, when the minor switch 23a is in the ON state in accordance with the operation of the minor operator 23, based on the determination of “NO” in Step 112 and the determination of “YES” in Step 113, the maximum of the key data MKD is determined in Step 115. The upper bit MSB is set to “0” representing a minor key, and at the same time, the lower bit of the same data MKD is the key pressed on the keyboard 10 and the key code for the highest key in the key pressing buffer register 83a. Set to KC. After the processing in steps 114 and 115, the key setting flag MKSF is set to "1" in step 116, and the program proceeds to step 118. As described above, if the key setting selection operation element 21 is set to the manual side, the processing of steps 112 to 116 causes the key data MK
D is set in accordance with the operation of the key operator 22 (or minor operator 23) of the key press and key setting operation panel unit 20 on the keyboard 10.

On the other hand, if neither the major switch 22a nor the minor switch 23a is in the ON state, the process of the chord determination routine similar to the above-described step 106 is performed in step 117 based on the determination of “NO” in both of the steps 112 and 113. Upon execution, the program proceeds to the key determination routine of step 111 described above.

In step 118, it is determined whether there is an ON event of the rhythm selection switch. In this case, if none of the operators in the rhythm selection operator group 31 is operated, it is determined in step 118 that “NO”, that is, there is no ON event related to the rhythm selection switch, and the program proceeds to step 124. If any of the operators in the rhythm selection operator group 32 is operated, step 118 is executed.
Is "YES", that is, it is determined that there is an ON event relating to the rhythm selection switch, and the program proceeds to steps 119 and 12.
The process proceeds to the determination process of 0. In step 119, it is determined whether the previously selected rhythm type represented by the rhythm type data RHY is blues and the newly selected rhythm type is other than blues, and in step 120, It is determined whether or not the previously selected rhythm type represented by the rhythm type data RHY is other than blues, and whether the rhythm type newly selected this time is blues. Now, if the selected rhythm type has been changed from blues to something other than blues, step 11
Based on the determination of “YES” in 9, after all the data in the key press key flag table 83f and the chord table 83g are cleared in step 121, the rhythm type data RHY is other than the blues in step 123. Is set to new data representing. If the selected rhythm type has been changed from something other than blues to blues, step 119
Determination of “NO” in step
Based on the determination of "S"
After all the data in 83h is cleared, in step 123 the rhythm type data RHY is set to new data representing the blues. On the other hand, if the two conditions are not met,
Based on the determination of “NO” in both steps 119 and 120, the program proceeds directly to step 123,
The rhythm type data RHY is set to new data representing the selected rhythm type.

In step 124, it is determined whether there is an ON event of the start / stop switch. In this case, if the start / stop operator 32 is not operated, it is determined in step 124 that “NO”, that is, there is no ON event related to the start / stop switch, and the program proceeds to step 128. If the start / stop operator 32 is operated, “YES” is determined in step 124.
That is, it is determined that there is an ON event related to the start / stop switch, and the rhythm run flag RUN is inverted in step 125 (from “0” to “1” or from “1” to “0”).
At the same time, the tempo count data TCNT is initialized to “0”. Next, in step 126, it is determined whether or not the new rhythm run flag RUN inverted by the above processing is "1". In this case, assuming that the rhythm has stopped before and a new operation is to be started this time, the rhythm run flag RUN is “1” and “YES” in step 126
Based on the determination, the performance start flag PSTF is
And the performance start minor flag PSTMF are both initialized to "0". Also, if the rhythm is running before and is stopped this time, the rhythm run flag RUN is “0”, and the program proceeds directly to step 128 based on the determination of “NO” in step 126.

Step 128 shows a routine for determining a melody, which will be described in detail later. In the routine, the melody being played is determined in accordance with chords, keys, etc., and the data representing the determined melody is the melody data SCALE. Is set as After the process of step 128, in step 129, operation event processing relating to other operators such as operators 33, 34, 41, and 42 in the rhythm control operation panel unit 30 and the other operation panel unit 40 is executed, and the tempo of the auto rhythm is executed. The tone color and volume of the generated tone signal are set and controlled.

Next, a chord determination routine, a key determination routine, and a trajectory determination routine executed by the main program will be described in detail.

Chord Judgment Routine The details of the chord judgment routine are as shown in the flowchart of FIG.
It is read out at 7 and its execution is started from step 200.

After the start, in step 201, all data in the key press key flag buffer register 83b and the chord detection buffer register 83c are cleared, and the buffer address is cleared.
BAAD and root count data RCNT are reset. As a result, the buffer address BAAD indicates the start address of the key depression key flag buffer register 83b and the chord detection buffer register 83c, and at the same time, the root count data RCNT (see FIG. 2D) is the key of the C sound as the reference sound. The code KC is shown. Next, at step 202, the key code K stored in the keypress buffer register 83a
Rotation register 83d based on C (see Figure 2D)
"1" is set only in the position of each bit corresponding to the key press sound in the above. For example, if the key press sounds are the C sound, the E sound, the G sound, and the B sound, “1” is set only in the positions 1, 3, 5, and 7 of the register 83d, and “0” is set in the remaining positions. "Is set. After the processing of step 202, a processing of a chord detection buffer data forming routine is executed in step 203.

This chord detection buffer data formation routine is shown in detail in FIG. 7, and the routine is started in step 300, and in step 301, the rotation register 83d
Are sequentially rotated from the right to the left in FIG. 2D until the most significant bit MSB becomes "1", and at the same time, the root count data RCTNT is incremented by "1" for each rotation. . Only the first bit is the most significant bit
If the MSB is "1", the program proceeds to step 302 without performing the rotation, and from then on, even if the most significant bit MSB is "1", the program proceeds to step 302 after the rotation is performed. Can proceed. After the processing of step 301, the root count data is obtained in step 302.
It is determined whether RCNT is greater than “11”. In this determination, if the number of rotations is small and the root count data RCNT is “11” or less, the program proceeds to steps 310 to 3 based on the determination of “NO” in step 302.
Proceed to the chord search routine consisting of 15.

In this chord search routine, the most significant bit MSB of the rotation register 83d is set to 1 ゜, 3 ゜,
A plurality of chords that may have been specified are detected based on whether or not a 5 ゜ sound, a 7 ゜ sound, and the like exist. In the following, nine types of chords that can be detected in the present embodiment and their detection methods will be described.

There are m7th chord 7 ° tones and 3 ° ^♭ sound, and in which is 5 ° ^♭ tone is detected on condition that there is no, step 310-312
The program is detected by the
Proceed to 1.

m7th ^(♭ 5) chord 7 ° sound, 3 intended ° ^♭ sounds and 5 ° ^♭ sound is detected on condition that there, are detected by the determination process of step 310-312, the program advances to step 322 Can be

The 7th chord is detected on the condition that the 7th and 3rd tones are present. The program is advanced to step 323 after being detected by the determination processing in steps 310 and 311.

7th (sus4) those chord 7 ° tones and 3 ° ^# sound is detected on condition that there, are detected by the determination process of step 310 and 311, the program proceeds to step 324.

Aug chord is detected on the condition that the 7th note does not exist and the 3rd note and the 5th ^# sound exist. The program is detected by the determination processing of steps 310 and 313, and the program proceeds to step 325.
Proceed to

Dim chord 7 ゜ tone does not exist, 3 ゜ note or 5 ゜^# note does not exist,
The program is detected on the condition that the 3 ゜^♭ sound and the 5 ゜^♭ sound are present. The program is advanced to step 326 after being detected by the determination processing of steps 310, 313 and 314.

The condition with Min chord 7 ° sound does not exist without satisfied, and in which 3 ° ^♭ sound is detected on condition that there, are detected by the determination process of step 310,313～315, the program steps Proceed to 327.

The Maj chord is detected on the condition that the 7th tone does not exist, the above condition is not satisfied, and the 3rd tone exists. The program is detected by the determination processing in steps 310, 313 to 315, and the program proceeds to step 328. Proceed to

The SUS4 chord is detected on the condition that the above-mentioned condition is not satisfied and the presence of the 3 ## sound while the 7 ^# sound does not exist, and is detected by the determination processing of steps 310, 313 to 315, and the program Proceed to 329.

By such a chord detection, the program is executed at steps 321-2-3.
In step 321 to step 329, the root count data RCNT and the type data TYPE such as m7th, m7th ( ^♭ 5), 7th are set as the root ROOT and type TYPE of the chord. The data is written to the address specified by the buffer address BAAD value of the register 83c (see FIG. 2C). After the processing of each of these steps 321-329,
In steps 331 to 339, the chord component sound table 91a (FIG. 3A) is referred to based on the written type TYPE, and the key depression key flag in the rotation register 83d is configured similarly to the register 83d12. The basic constituent sound and the tension sound stored in the chord constituent sound table 91a from the key-pressed key flag (“1”) transferred to another register (not shown) of the bit as it is and transferred to the other register. Are deleted as misnotes and rotated rightward by the root ROOT (the number of rotations), and then the key press key flag data in the other register is stored in the key press key flag buffer register 83b. (See FIG. 2B) The buffer address is written to the address specified by the BAAD value. This allows
The key-depressed key flag from which the miss note has been removed and which has been returned to the key-depressed state is written to the address of the key-depressed key flag buffer register 83b. Next, step 341
At 349 to 349, the chord component sound table 91a is referred to again based on the type TYPE, and the number of tension sounds TENSU and the minimum tension sound number LTNO are detected by the key depression key flag in the rotation register 83d, and the number of tension sounds TE
The NSU and the minimum tension tone number LTNO are respectively written to addresses specified by the buffer address BAAD value of the chord detection buffer register 83c. Note that such steps
In the processing of 341 to 349, naturally, the miss note is not considered, but the key depression key flag ("1") corresponding to the miss note is also left in the rotation register 83d for the next chord detection processing. .

After the processing in steps 341 to 349, the buffer address BAAD is increased by "1" in step 351 and the program returns to step 301. And, again, the above steps 301, 302, 310-315, 321-329, 331-339, 341-349
Is performed. Further, in the chord search routine, when a chord having the most significant bit MSB as a root is not detected, that is, when it is determined as “none” in steps 311 and 315, the buffer address BAAD is not advanced. , The program returns to step 301 to execute a new chord search again at steps 301, 302, 310 to 315, 3
The processing of 21 to 329,331 to 339,341 to 349 is executed. As a result, chords each of which is likely to be the root note of each depressed tone are sequentially written to the chord detection buffer register 83c, and the depressed key flags excluding misnotes are depressed in correspondence with the chord detection buffer register 83c. The data is written to the key key flag buffer register 83b. In this state, when the number of rotations increases and the root count data RCNT becomes 12 or more, step 302
Is determined to be "YES", the processing of the chord detection buffer data forming routine is terminated in step 303, and the program proceeds to step 204 of the chord determination routine in FIG.

In step 204, it is determined whether or not the key setting flag MKSF is "1". As described above, this key setting flag MKSF indicates “before key setting” with “0” and indicates after key setting with “1”.
Based on the determination of “NO” in 204, the processing of the first chord detection routine is performed in step 205. After the key setting, the process of the second chord detection routine is performed in step 206 based on the determination of “YES” in step 204. After the processing of steps 205 and 206, step 2
At 07, the execution of the chord determination routine ends.

Next, the first chord detection routine will be described. Execution of the routine is started in step 400 of FIG.
In step 401, it is determined whether chord data such as root ROOT and type TYPE exists in the chord detection buffer register 83c. In such a case, the chord detection buffer register 83
If there is chord data in c, “YE
In step 402, the chord data in the chord detection buffer register 83c with the smallest number of tension notes TENSU is searched. After such a search, step 40
At 3, it is determined whether or not there are a plurality of pieces having the minimum number of tension sounds TENSU. If there is a plurality of chord data searched, the number of tension sounds TENSU is determined in step 404 based on the determination of “YES” in step 403.
Is the lowest tension note number from the smallest chord data
After the chord data corresponding to is searched, step 405
The root ROOT and the type TYPE related to the searched chord data are set and stored as key pressed chord data DPCHD. If there is only one chord data searched in step 402, the program proceeds directly to step 405 based on the determination of “NO” in step 403, and the tension sound is detected in step 405. The root ROOT and the type TYPE related to the chord data having the smallest number TENSU are set and stored as the key pressed chord data DPCHD. These steps 402
By the processes of 405 to 405, the safest chord without using the key data MKD, that is, the chord with the lowest tension, is determined.

After the processing in step 405, the key depression chord data DPCHD representing the chord determined in step 406 is replaced with the Aug chord or Di chord.
It is determined whether or not the chord data indicates a chord, and the chord data D is determined.
If PCHD indicates an Aug chord or a Dim chord, step 40
Based on the determination of “YES” in 6, the execution of the first chord detection routine is ended in step 411. If the chord data DPCHD does not indicate an Aug chord or a Dim chord, a key press key used to determine the key by the processing of steps 407 to 409 based on the determination of “NO” in step 406. A process of storing data in the flag table 83f and the chord table 83g is executed. That is, at step 407, "1" is added to the current table address CTAD (modulo 8), and at step 408, the root of the key pressed chord data DPCHD is added to the address of the chord table 83g specified by the same address CTAD. The sound ROOT and the type TYPE are written, and at step 409 the key press key flag in the key press key flag buffer register 83b corresponding to the key press chord data DPCHD at the address of the key press key flag table 83f specified by the same address CTAD. Is stored, and step 411 is stored.
The execution of the first chord detection routine ends. As a result, when a chord is detected, chord data other than the Aug chord or the Dim chord is written into the chord table 83g, and the key-pressed key flag from which the misnote has been deleted is written into the key-pressed key flag table 83f. If so, use the Aug
The reason for excluding chords and Dim chords is that these chords change the chord progression of the music, and if the chords are used for key determination, key determination will not be made accurately. Further, the addition operation in the step 407 is performed by the key press key flag table 83f.
And the address of the chord table 83g are repeatedly specified. At the same time, when the first and second tables 83f and 83g are specified in the initial state, the first (0) address is specified. The current table address CTAD is set to the last address value of both tables 83f and 83g.

On the other hand, if it is determined in step 401 that “NO”, that is, that there is no chord data in the chord detection buffer register 83c, the key depression chord data DPCHD is set to data indicating that chord is not established in step 410, and The execution of the first chord detection routine ends. Thus, even when the chord is not established, the address CTAD is not updated and the previous address CTAD is maintained as in the case where the detected chord is the Aug chord or the Dim chord.

By executing the first chord detection routine consisting of steps 400 to 411, the first chord detection routine is performed for each key press on the keyboard 10 before the key is determined. Therefore, except for the initial state, the key press key flag table 83f and the chord table 83g store the last eight chord data used for key setting.

Next, a description will be given of a second chord detection routine executed after the key is set, that is, when it is determined to be “YES” in step 204 (FIG. 6). Execution of this routine is 9A
The process starts in step 500 in the figure, and in step 501, the root ROOT and the type TYP in the chord detection buffer register 83c.
The presence or absence of chord data such as E is determined. In such a case, the aforementioned chord detection buffer data formation routine (FIG. 7)
If the chord data is not stored in the chord detection buffer register 83c by the above processing, it is determined as "NO" in the step 501, and the first chord detection routine (the eighth chord detection routine) is executed.
In the same manner as in FIG. 9, the chord failure data is designed as the key pressed chord data DPCHD in step 502, and the execution of the second chord detection routine is terminated in step 503.

If there is chord data in the chord detection buffer register 83c at the time of the determination in step 501, "YES" is determined in step 501, and the priority chord flag PCDF is initialized to "0" in step 504. At the same time, it is determined in step 505 whether or not a chord satisfying the following priority condition 1 exists in the chord detection buffer register 83c with respect to the chord represented by the immediately preceding chord, that is, the key depression chord data DPCHD.

Priority condition 1 The chord type TYPE changes from 7th or 7th (SUS4) to Maj, and the chord root ROOT drops by one or seven notes in semitone intervals, that is, the transition of the chord matches the final type. thing.

If a chord that matches the priority condition 1 exists in the chord detection buffer register 83c, the “YE
In step 506, the root ROOT and the type TYPE of the chord data in the chord detection buffer register 83c that match the priority condition 1 are keyed chord data DPCH.
D is set and stored, and the above steps 407 to 40
Step 507 in the same manner as 9 (first chord detection routine)
In step 508, a "1" is added to the current table address CTAD (modulo 8), and in step 508, the root ROOT and type of the depressed chord data DPCHD are stored in the address of the chord table 83g specified by the same address CTAD. The TYPE and the chord tension level CTENL are written, and in step 509 the key press key flag table 83 specified by the same address CTAD
At the address f, a key depression key flag in the key depression key flag buffer register 83bb corresponding to the key depression chord data DPCHD is stored. In addition, in the processing of step 508,
Since the key has already been set, the key data MKD is subtracted (modulo 12) from the root ROOT of the key pressed chord data DPCHD, and the chord data in the frequency display, that is, the C key, together with the type TYPE of the key pressed chord data DPCHD is obtained. Chord data based on the chord is derived, and the chord tension level CTENL stored in the chord tension table 91b is read out by referring to the chord tension table 91b (FIG. 3C) according to the chord data. CTENL is written to the chord table 83g. As a result, a chord based on the musical end theory is preferentially determined. After the processing in step 509, the priority chord flag PCDF is changed to "1" in step 510, and the program proceeds to step 511.

On the other hand, if the determination in step 505 is "NO", that is, if it is determined that there is no chord meeting the priority condition 1 in the chord detection buffer register 83c, the program proceeds directly from step 505 to step 511. In this case, the priority chord flag PCDF remains set to “0”.

In step 511, for the chord represented by the immediately preceding chord, that is, the chord data DPCHD, a chord meeting the following priority condition 2 or 3 is extracted from the chord detection buffer register 83c.

Priority condition 2 The chord has shifted from the second chord group shown in the chord tension table 91b (FIG. 3C) to the third or fourth chord group.

Priority condition 3 The chord has shifted from the fifth chord group shown in the chord tension table 91b (FIG. 3C) to the sixth or seventh chord group.

In the extraction, as in the case described above, the chord tension table 91b is referred to based on the chord data DPCHD, the chord data and the key data MKD in the chord detection buffer register 83c, and the extracted data is temporarily stored. Is memorized.

Next, at step 512, the presence or absence of the extracted data is determined. In such a case, if the extracted data exists, the step
Based on the determination of "YES" in 512, steps 513-520
After the processing of, the program proceeds to step 521 (FIG. 9B). If there is no extracted data, step 51
Based on the determination of “NO” in 2, the program proceeds directly to step 521.

In step 513, it is determined whether or not the extracted chord data includes any of the extracted chord data and the chord indicated by the immediately preceding chord, that is, the chord indicated by the key depression chord data DPCHD, which satisfies the following priority condition 4. You.

Priority condition 4 The chord has shifted from the immediately preceding chord to a perfect fourth higher chord.

In such a case, the root ROOT of the extracted chord data is subtracted (modulo 12) from the root ROOT of the key pressed chord data DPCHD, and it is determined whether or not the subtraction result is “5”. If there is any extracted chord data that satisfies the priority condition 4, "YES" is determined in the step 513.
At 514, the root ROO of the chord data that matches the priority condition 4
T and type TYPE are set as the key press chord data DPCHD. If none of the extracted chord data matches the priority condition 4, "NO" is determined in step 513, and in step 515, any one of the extracted chord data is determined according to a predetermined condition (for example, First, the root note ROOT and the type TYPE of the selected chord data are set as the key pressed chord data DPCHD.

After the processing in steps 514 and 515, it is determined in step 516 whether or not the priority chord flag PCDF is “1”. In this determination, if “YES” is determined, that is, if the priority chord flag PCDF has already been set to “1” by the processing in step 510, the current table address CTAD is set in step 517 in the same manner as in steps 508 and 509. The root note ROOT, the type TYPE, and the chord tension level CTENL of the set depressed chord data DPCHD are written to the address of the chord table 83g specified by, and the depressed key flag specified by the same address CTAD in Step 518. The key depression key flag in the key depression key flag buffer register 83b corresponding to the key depression chord data DPCHD is stored in the address of the table 83f. In this case, since the current table address CTAD is not advanced, the chord table 83g and the key press key flag table 8
Each data written in 3f will be rewritten. In step 516, the determination is "NO", that is, if the processing in steps 506 to 510 is not performed, the priority chord flag PCDF is set to "1" in step 519.
And at step 520 the above step 5
After the current table address CTAD is advanced in the same manner as in the process of 07, the processes of steps 517 and 518 are performed. As a result, in such a case, in the chord table 83g and the key depression key flag table 83f, which have been advanced by the storage address of the previous various data having a good “1”, the root ROOT and the type corresponding to the key depression chord data DPCHD are stored. TYPE, chord tension level CT
The ENL and the key press key flag are written. By the processing of steps 511 to 518, an appropriate chord is preferentially determined with respect to the progression of musical chords.

After the processing in step 518, the program proceeds to step 521 in FIG. 9B, where it is determined whether or not the final key is minor. In this case, if the definitive key is the minor key, the program proceeds to step 522 to determine whether or not the key data MKD indicates the minor key. Proceed to step 535. Further, if the definitive key is a major key, based on the determination of “NO” in step 521,
The program proceeds directly to step 535.

The minor priority routine will be described. After the determination in step 521, it is determined in step 522 whether or not the primary cadence chord flag PCCF is “0”. In such a case, if the cadence chord has been previously selected and the flag PCCF is “1”, “YE
Is determined to be "S", and in steps 523 and 524, it is determined whether there is a primary chord or a cadence chord in the chord detection buffer register 83c. This determination is made based on the frequency-displayed chord data obtained by subtracting (modulo 12) the key data MKD from the root ROOT of each chord data in the chord detection buffer register 83c and the type TYPE of each chord data. This is performed by referring to the / cadence chord table 91c. If there is a primary chord in the chord detection buffer register 83c, "YES" is determined in step 523, and the primary cadence chord flag PCCF is changed to "0" representing the primary chord in step 525. In step 526, the root ROOT and the type TYPE of the chord data meeting the above conditions are the key pressed chord data DPCHD.
Is set as Also, the chord detection buffer register 83
If there is no primary chord and there is a cadence chord in c, “NO” is determined in step 523 and “YES” is determined in step 524. In step 527, the primary cadence chord flag PCCF is set to the cadence chord. Is set again to “1” indicating the above, and the process of step 526 is executed. Further, if there is no primary chord or cadence chord in the chord detection buffer register 83c, the step
At 523 and 524, each is determined as “NO”, and the program proceeds to step 535.

On the other hand, if the primary chord has been previously selected and the flag PCCF is “0”, then “N
In step 528 and step 529, it is determined whether there is a cadence chord or a primary chord in the chord detection buffer register 83c in the reverse order to that described above. Note that such determination is also made in steps 523 and 524 described above.
The method is performed in the same manner as described above. If there is a cadence chord in the chord detection buffer register 83c, "YES" is determined in step 528, and the primary cadence chord flag PCCF is changed to "1" representing the cadence chord in step 527. In step 526, the root ROOT and the type TYPE of the chord data meeting the above condition are set as the key pressed chord data DPCHD. Also, the chord detection buffer register 83c
If there is no cadence chord and there is a primary chord
In step 528, the determination is "NO" and step 5
It is determined to be "YES" in 29, the primary cadence chord flag PCCF is reset to "0" representing the primary chord in step 525, and the processing in step 526 is executed. Further, if there is no primary chord or cadence chord in the chord detection buffer register 83c, steps 528, 52
In step 9, the determination is “NO”, and the program proceeds to step 535.

After the processing in step 526, step 516 in FIG. 9A is performed.
Similarly to the processing of steps 518 to 518, in the processing of steps 530 to 532, if the priority chord flag PFDF has already been set to "1" in the previous processing, the chord table 83g and the key depression key flag table 83f have already been written. The root ROOT, the type TYPE, the chord tension level CTENL, and the key depression key flag corresponding to the latest key depression chord data DPCHD are rewritten. If the priority chord flag PCDF has not yet been set to “1” in the previous processing, the priority chord flag PCDF
Is newly set to "1", and after the current table address CTAD is advanced, each address of the chord table 83g and the keypress key flag table 83f, which is advanced by "1" from the storage address of various data before. Then, a root note ROOT, a tie TYPE, and a key pressed key flag corresponding to the key pressed chord data DPCHD are newly written. Through the processing of steps 522 to 534, the primary chord and the cadence chord are alternately selected as much as possible, and a chord appropriate to the progression of musical chords in minor is preferentially determined.

After the processing of steps 521,524,529,532, step 5
At 35, it is determined whether or not the priority chord flag PCDF is "1". In such a case, the chord is already selected with priority and the flag
If PCDF is "1", "YES" is determined in the step 535, the program proceeds directly to the step 542, and the execution of the second chord detection routine is ended in the step 542. If the priority of the chord has not yet been selected and the priority chord flag PCDF is “0”, “N”
O, and in step 536, the chord tension level CTE is set for each chord in the chord detection buffer register 83c.
NL is written. Such chord tension level CTENL
When writing the note, subtract the pitch indicated by the key data MKD from the root ROOT of each chord data (modulo 12)
The chord tension level CTENL is read from the chord tension table 91b by referring to the chord tension table 91b based on the root ROOT of the chord data represented by the frequency and the type TYPE of the key depression chord data DPCHD represented by the subtraction result. The level CTENL is stored in the chord detection buffer register 83c.
To be added to the chord data inside. However, Aug
For chords and Dim chords, chord tension table 9
Chord tension level CTEN is not stored in 1b,
For the two chords, the same level CTENL is not written in the chord detection buffer register 83c.

After the processing in step 537, it is determined in step 537 whether chord data meeting the following chord tension transition condition exists in the chord detection buffer register 83c.

Chord tension transition condition When the chord tension level CTENL rises, it gradually changes (for example, 0 or more and less than +3), and the same level CTEN
When L falls, it changes abruptly (for example, less than -3) so that the chord tension level CTENL changes like a sawtooth wave.

In this determination process, the root ROOT, the type TYPE, and the key data MKD of the chord represented by the immediately preceding chord, that is, the key depression chord data DPCHD, as in step 536 described above.
By referring to the chord tension table 91b, the chord tension level CTENL * of the immediately preceding chord is derived, and the derivation level CTENL * and the chord tension level CTENL for each chord stored in the chord detection buffer register 83c are derived. And 0 <CTENL−CTENL *
Search for a chord with a chord tension level CTENL that matches <+3 or CTENL−CTENL * <− 3.

In such a case, if a chord that matches the chord tension transition condition is found, as soon as the chord is found, it is determined to be “YES” in Step 537, and the processing in Steps 538 to 541 similar to the processing in Steps 526, 534, 531 and 532 causes the condition to be satisfied. The root chord ROOT and the type TYPE of the matched chord data are set as the depressed chord data DPCHD, and the current table address CTAD is advanced, and the chord table 83g is advanced by "1" from the storage address of the previous various data. And the key depression chord data DPCHD at the address of the key depression key flag table 83f.
, The root ROOT, the type TYPE, the chord tension level CTENL, and the key depression key flag corresponding to. And
After the processing in step 541, the execution of the second chord detection routine is ended in step 542. Step 536 like this
By the processes of 541 to 541, an appropriate chord along the chord tension level line indicating the progress of the chord is determined.

On the other hand, in the chord detection buffer register 83c, if there is no chord data matching the chord tension transition condition, it is determined as `` NO '' in step 537, and the program proceeds to step 543 in FIG. 543-551
The chord is determined by the above processing. These steps 543
The processing of ~ 551 is the chord tension level in step 549.
Except that CTENL is written in the chord table 83g (similar to the process of step 531 in FIG. 9B), the process is the same as the process of the first chord detection routine in FIG. As a result, from the chord data stored in the chord detection buffer register 83c, the chord having the smaller number of chord tension TENSU and the lowest tension tone number LTNO is determined as the designated chord.

Key Determination Routine Next, the key determination routine will be described. The execution of this key determination routine is started from step 600 in FIG. 10A,
In step 601, the current chord, that is, the key depression chord data DPCHD
Indicates a chord failure, an Aug chord or a Dim chord, "YES" is determined in step 601 and the execution of the key determination routine is terminated in step 602. Thus, in such a case, the key determination processing is not substantially performed.

If the current chord does not indicate chord failure, Aug chord or Dim chord, it is determined in step 603 whether or not the selected rhythm is blues based on the rhythm type data RHY. This determination is because the determination condition greatly differs depending on whether the selected rhythm is blues or not in the key determination.

First, the case where the selected rhythm is other than blues will be described. "NO" is determined in step 603, and the program proceeds to steps 604 and 605, the major key determination motive routine. In step 604, if the current chord is a semitone interval from the immediately preceding chord to the root ROOT, then
It is determined whether the sound has dropped. In this judgment, the root RO of the chord data stored at the address immediately before the current table address CTAD in the chord table 83g is determined.
Is compared with the root note ROOT of OT and depressed chord data DPCHD, for example, to change the note C from root ROOT is G sound, if changes to the note C from D ^♭ tone, "YES" at step 604 Is determined, and the program proceeds to step 605. In this step 605, the relationship from the immediately preceding chord to the current chord has shifted from the Maj chord to the Maj chord, from the 7th chord to the Maj chord, or from the 7th (SUS4) chord to the Maj chord for the type TYPE. Is determined. Also in this determination, the current table address C of the chord table 83g is
The type TYPE of the chord data stored at the address immediately before the TAD is compared with the type TYPE of the key pressed chord data DPCHD, for example, the chord shifts from G _Maj to C _Maj , or G
_{When the} process shifts from _7th to C _Maj , “YES” is determined in step 605, and the provisional tone data KMKD is determined in step 606.
The most significant bit MSB is set to "1" indicating a major tone.

On the other hand, the root ROOT and the type TYPE are the same as those in steps 604 and 60.
If the relationship is not specified in step 5, the same steps 604, 6
In any of 05, it is determined to be "NO" and the program proceeds to a minor determination motive routine consisting of steps 607 to 609. In step 607, it is determined whether or not the performance start minor flag PSTMF indicating "one of the chords at the start of the performance was the Min chord or the m7th chord", which is one condition for determining the minor key, is "1". In this case, if the performance start minor flag PSTMF is “0”, it is determined that the minor key determination condition is not met, and “NO” is determined in step 607, and the key determination routine is ended in step 611.
If the performance start minor flag PSTMF is “1”,
Based on the determination of “YES” in the step 607, it is determined in a step 608 whether or not the current chord has dropped by seven semitones with respect to the root ROOT from the immediately preceding chord. Also in this determination, the root ROOT of the chord data stored at the address immediately before the current table address CTAD in the chord table 83g is compared with the root ROOT of the key pressed chord data DPCHD. Is changed from the G sound to the C sound, "YES" is determined in step 608, and the program proceeds to step 609. In this step 609, the relationship from the immediately preceding chord to the current chord is determined by the type TYPE
Regarding, transition from Maj chord to Min chord or 7th chord to M
It is determined whether or not the transition to the in chord is made. In this determination, the type TYPE Type TYPE and depressed chord data DPCHD chord data stored in the previous address from the current table address CTAD in chord table 83g are compared, for example, chords from G _{Maj Move} to C _Min or from G _7th
In the case of shifting to C _Min , “YES” in step 609
In step 610, the most significant bit MSB of the temporary tone data KMKD is set to "0" indicating a minor tone.

On the other hand, the root ROOT and the type TYPE are the same as those in steps 608 and 60.
Step 608,609
Is determined to be "NO", the program proceeds to step 611, where the key determination routine is ended.

When the program proceeds to steps 606 and 610 by the processing of steps 604, 605 and 607 to 609, the key corresponding to the root ROOT of the key pressed chord data DPCHD or a key five degrees higher than the root ROOT (for example, the root ROOT) If is the C tone, the determination of C or G tone is expected, and the determination process consisting of steps 612 to 619 is further continued in order to determine either tone. In step 612, each chord in the chord table 83g is a root note of the key depression chord data DPCHD.
Using ROOT as a reference key, the frequency is converted to a frequency display (root ROOT of chord in chord table 83g-root ROOT of key pressed chord data DPCHD). The chord tension level CTENL is derived, and the eight chord tension levels are obtained.
The sum of CTENL is calculated as the first tension level sum SUMTENL1. Next, at step 613, in the same manner as at step 612, the chord tension for the past eight chords in the chord table 83g is set, using a key (ROOT + 7) that is five times higher than the root ROOT of the key depression chord data DPCHD as a reference key. The sum of the levels CTENL is calculated as the second tension level sum SUMTENL2.

After the processing of steps 612 and 613, in step 614, the first and second tension level sum values SUMTENL1, SUMTE
The magnitude relationship of NL2 is compared. Now, the first tension level sum SUMTENL1 is equal to the second tension level sum SUMTEN
If it is smaller than L2, it is determined that the provisional key is the one represented by the root ROOT of the key depression chord data DPCHD (for example, the C key if the root ROOT is C), and in step 615, the provisional key is determined. The root ROOT is stored in the lower bits of the data KMKD.
Conversely, if the second tension level sum value SUMTENL2 is smaller than the first tension level sum value SUMTENL1, the provisional key is ROOT + 7 (for example, the root tone ROOT is higher than the root tone ROOT of the depressed chord data DPCHD by five degrees). At step 616, the value ROOT + 7 is stored in the lower bits of the provisional tone data KMKD.

Further, if the two sums SUMTENL1 and SUMTENL2 are equal, the program proceeds to steps 617 to 619 by the determination in step 614. In the processing of steps 617 to 619, in the key depression names of the past eight chord depressions, the root ROOT is assigned an IV degree tone (for example, the root ROOT
If the sound is F), there is an IV ^# for the same root ROOT
It is determined whether there is a degree sound (for example, F ^# sound if the root ROOT is C sound). That is, at step 617, a value obtained by adding “5” to the root ROOT of the key pressed chord data DPCHD, ROOT + 5
The key depression key flag table 83f is referred to based on the value ROOT + 6 obtained by adding "6" to the root ROOT of the key depression chord data DPCHD in steps 618 and 619. If the IV degree tone is present in the key depression key flag table 83f and the IV ^# degree tone is not present in the table 83f, “YES” is determined in step 617.
In addition, it is determined as “NO” in step 618 (it is determined that the provisional key is represented by the root ROOT of the key depression chord data DPCHD), and the processing in step 615 is performed. On the other hand, if the IV ^# degree tone exists in the key depression key flag table 83f and the IV degree tone does not exist in the table 83f, "NO" in step 617 and "YES" in step 617.
(Temporary key is root note of keypress chord data DPCHD ROOT
+7), and the process of step 616 is performed. Further, if both the IV and IV ^# degrees are present or absent in the key depression key flag table 83f, “YES” is determined in steps 617 and 618, respectively.
Alternatively, “NO” is determined in steps 617 and 619, respectively, and in step 611, the processing of the key determination routine is ended.

As described above, if the selected rhythm is other than blues, the provisional key is determined by the processing of steps 604 to 619, and the provisional key data KMKD is set by the processing of steps 606, 610, 615, and 616, and the program proceeds to the step of FIG. 10B. 628
Proceed to

On the other hand, if the selected rhythm is blues, “YES” is determined in step 603, and the program proceeds to step 10B.
Proceed to step 620 in the figure. In step 620, all data in the blues table 83h (FIG. 2G) is cleared, and in step 621 the chord table 83g (FIG. 2F)
Out of the last eight chord data, a chord of type 7th is extracted, and the root chord ROOT of each extracted chord is extracted.
Each storage location (ROOT,
The chord flags DFLG of (I _7th ), (ROOT + 7, IV _7th ), and (ROOT + 5, V _7th ) are each set to “1”. This is because the _7th chord that modulates the root ROOT is the ROOT + 7 tone.
V _7th chords to adjust the _7th chords and ROOT + 5 sound to be because it is conceivable. Next, in step 622, a chord of type m7th is extracted from the last eight chord data of the chord table 83g (FIG. 2F), and for each root ROOT of each extracted chord, Each storage location (ROOT, I _m7th ), (ROOT + 7, IV _m7th ), (ROOT + 5,
V _m7th ) is set to “1”. This is because the _Im7th chord that _{modulates the} root ROOT
+7 tones IV _m7th chord and ROOT +5 tones
This is because it is also considered a V _m7th chord.

After the processing in steps 621 and 622, it is determined in step 623 whether or not there is a root ROOT in which the chord flags DFLG for all the chords I _7th , IV _7th and V _7th are “1” in the blues table 83h. Rutotomoni, I _m7th at step 624 in the blues table 83h, IV _m7th, whether the chord flag DFLG for each chord V _M7th is neon ROOT are all "1" exists is determined. This is because the following blues conditions 1 and 2 are used as the conditions for judging the tone in blues.

Blues condition 1 When all the chords I _7th , IV _7th , V _7th appear in the past eight chords, it is determined to be a major.

Determining in the blues condition 2 past eight chords, I _m7th, IV _m7th, a minor when all chord V _M7th appeared.

Assuming that the blues condition 1 is satisfied, "YES" is determined in step 623, and in step 625, the most significant bit MSB of the temporary tone data KMKD is set to "1" representing a major tone. The lower bit of the data KMKD is set in the corresponding root ROOT. If the blues condition 2 is satisfied, “NO” in step 623 and
Is determined as “YES”, and in step 626, the provisional tone data KM
The most significant bit MSB of KD is set to “0” indicating minor, and the lower bit of the same data KMKD corresponds to the root note ROOT.
Is set to Further, if the blues conditions 1 and 2 are not satisfied, it is determined “NO” in both steps 623 and 624, and the process of the key determination routine is ended in step 627.

Thus, if the selection rhythm is blues,
The provisional key is determined by the processing of steps 620 to 624, and the provisional key data KMKD is determined by the processing of steps 625 and 626.
Is set, and the program proceeds to step 628.

In step 628, the key data MKD and the provisional key data KM
Each most significant bit MSB of KD is compared to determine whether the previously determined key and the set temporary key are the same in terms of length. If the lengths are the same, step 62
In step 629, it is determined as "YES", and based on the rhythm type data RHY (whether or not it is blues) and the temporary key data KMKD, the rhythm type (blues and other types) in the key flag table 83i (Fig. ), The storage position corresponding to the length and the duration and the note name are designated, and “1” is added to the key flag KFLG of the designated storage position. However, the key flag KFLG changes from 0 to 3, and the addition is not performed when the key flag KFLG is already “3”. next,
At step 630, rhythm type data RHY and provisional tone data KM
The key flag table 83i is again referred to based on the KD and the key data MKD, and the key flag KFLG * relating to the previously determined key (key data MSD) and the key flag KFLG relating to the present detected key (temporary key data KMKD) are compared. You. In this case, if the key flag KFLG * is larger than the key flag KFLG, step 630
Is determined to be "NO" and the execution of the key determination routine is terminated in step 634, so that the previously determined key is not changed. This is because if the key is changed with a small amount of information, an error may occur in the determination of the key (judgment of the modulation).

On the other hand, as a result of the addition operation of the key flag KFLG, the key flag
If KFLG is greater than or equal to the key flag KFLG *, "YES" is determined in step 630, and in step 631, the key data MKD is set to the value indicated in the temporary key data KMKD. This allows
The performance tone of the electronic musical instrument is determined or changed for the first time. After the processing of the step 631, the table 83i is set to an initial state by clearing all data in the key flag table 83i in a step 632, and the key flag table 83i is set based on the rhythm type data RHY and the key data MKD. The key flag KFLG at the storage position corresponding to the rhythm type, length and pitch and note name in 83i (the key flag KFLG subjected to the addition operation by the processing of the step 630) is set to "1", and the key is set in the step 633. After the flag MKSF is set to “1”, the execution of the key determination routine is terminated in step 634.

When the previously determined key (key data MKD) and the set temporary key (temporary key data KMKD) are different in length, the determination processing in step 628 described above indicates that “N
It is determined as "O", and the program proceeds directly to step 631, where the processing of steps 631, 632, and 633 is performed. In such a case, the process of steps 629 and 930 (the determination process regarding the key flag KFLG) is not performed, and the key is immediately changed. As a result, the key change from the major key to the minor key or from the minor key to the major key is performed with priority. Will be.

Turning Method Routine Next, the turning method determination routine will be described with reference to the flowchart in FIG. The method of determining this rotation depends on whether the key has not yet been determined, the key has already been determined, and the selected rhythm is not blues, and the key has already been determined and the selected rhythm is blues. Therefore, three cases will be described below.

In the case where the key is not yet determined In this case, since the key setting flag MKSF remains set to “0”, after the start of the trajectory determination routine in step 700, “NO” in step 701, that is, the key setting flag MKSF Is not "1", and it is determined in step 702 whether or not the key pressed chord data DPCHD corresponding to the current chord indicates that the chord is not established. If the key depression chord data DPCHD does not indicate that a chord is not established, "NO" is determined in step 702, and in step 703, the second modality table 91e (FIG. 3F) based on the key depression chord data DPCHD. Is read from the table 91e, and a modal name (for example, Ionian for Maj chord, Durian for Min chord) corresponding to the type TYPE of the key pressed chord data DPCHD is read and set as the modal data SCALE. Then, in step 705, the execution of the lane determination routine is terminated.

On the other hand, if the key depression chord data DPCHD indicates that a chord is not established, "YES" is determined in step 702, and in step 704, the immediately preceding detected chord (excluding the Aug chord and the Dim chord), that is, the chord Second based on the latest chord data indicated by the current table address CTAD in the table 83g
The turning table 91e is referred to, the turning data SCALE is set in the same manner as in the case of the step 703, and the step 705 is performed.
The execution of the turning determination routine is terminated. If no chord data exists in the chord table 83g immediately after the start of the performance, the modality data is not read from the chord table 83g, and the modality data SCALE is not set.

By the processing of steps 702 to 704, a method that is not musically safe, but lacks some accuracy, is determined.

In the case where the key has already been determined and the selected rhythm is not blues. In such a case, since the key setting flag MKSF has already been set to “1” and the rhythm type data RHY does not represent blues, the process proceeds to step 700. After the start of the trajectory determination routine, “YES” is determined in step 701, and “NO” is determined in step 706.
In the same manner as in step 702, the key depression chord data D
It is determined whether or not PCHD indicates that a chord is not established.
If the key pressed chord data DPCHD does not indicate that a chord is not established, "NO" is determined in step 707, and in step 708, the first key pressed chord data DPCHD is converted to a frequency display. Referring to the rotation table 91d (FIG. 3E), the rotation name is read from the table 91d and set as the rotation data SCALE. That is, the note name data of the key data MKD is subtracted from the root ROOT of the key pressed chord data DPCHD, and the result of the subtraction is compared with the type T of the key pressed chord data DPCHD.
The first rotation table 91d is referred to according to YPE, and the name of the rotation (for example, Ionian for I _Maj , Durian for II _m7th ) is read. Note that the chord data of the frequency display is the second group or later (the chord tension table in FIG. 3C).
91b), the name of the method for each group (for example,
If it is a chord of the fourth group, mixolidian, etc.) is read. Then, in step 705, the execution of the lane determination routine is terminated.

On the other hand, if the key pressed chord data DPCHD indicates that a chord is not established, "YES" is determined in step 707, and in step 709, the immediately preceding detected chord (excluding the Aug chord and the Dim chord), that is, the chord The first modality table 91d is referred to based on the latest chord data indicated by the current table address CTAD in the table 83g converted to a frequency display, and the modality data SCA is obtained in the same manner as in step 708.
LE is set, and in step 709, the execution of the turning determination routine is terminated.

Through such processing of steps 707 to 709, a musically appropriate melody is determined.

In the case where the key is already determined and the selected rhythm is blues In such a case, since the key setting flag MKSF is already set to “1” and the rhythm type data RHY represents blues, step 700 After the start of the trajectory determination routine in step 701, it is determined in step 701 and 706 that each is “YES”, and then in step 710, as in steps 702 and 707, whether or not the key pressed chord data DPCHD indicates that chords are not established. Is determined. Now, the key press chord data DPCH
If D does not indicate that the chord is not established, it is determined “NO” in step 710, and in step 711, the key depression chord data D
Chord data converted from PCHD to frequency display is I _7th , IV _7th , V
It is determined whether the chord is any of the _7th chords. That is, the key data M is obtained from the root ROOT of the key pressed chord data DPCHD.
Result of subtracting KD note name data and key press chord data DPCHD
It is determined whether the chord represented by the type TYPE corresponds to any one of the _I7th , _IV7th , and _V7th chords. In such a case, the power display chords I _7th, if any of the respective chord IV _7th, V _7th, the decision is "YES" at the same step 711, modal data SCALE at step 712 blues modal In step 705, the execution of the turning judgment routine is terminated.

Also, if “NO” is determined in step 711,
The program proceeds to step 713, where it is determined whether or not the chord data obtained by converting the key press chord data DPCHD into a frequency display is any of the chords of _Im7th , _IVm7th , and _Vm7th. . That is, the result of subtracting the note name data of the key data MKD from the root ROOT of the key pressed chord data DPCHD and the chord represented by the type TYPE of the key pressed chord data DPCHD are the chords of _Im7th , IV _m7th , and _Vm7th . It is determined whether any of the above is applicable. In such a case, the frequency display chord is I
If any of the chords of _m7th , IV _m7th and V _m7th correspond,
In step 713, the determination is "YES". In step 714, the mode data SCALE is set to data representing the minables mode, and in step 705, the execution of the mode determination routine ends.

Further, in both steps 711 and 713, "N
O '', that is, when it is determined that the chord data obtained by converting the key press chord data DPCHD into frequency display does not correspond to any of the chords of I _7th , IV _7th , V _7th , _Im7th , IV _m7th , _Vm7th , The program proceeds to step 707, wherein steps 707 to 709 are performed.
The rotation is determined by the processing of.

On the other hand, if the key pressed chord data DPCHD indicates that a chord is not established, "YES" is determined in step 710, and in step 715, the immediately preceding detected chord (excluding the Aug chord and the Dim chord), that is, the chord latest that the chord data is converted to degrees appears I _7th indicated by the current table address CTAD in the table 83 g, IV _7th, with whether them falls under any of the chord V _7th is determined, In step 716, it is determined whether or not the converted frequency-displayed chord corresponds to any one of the _Im7th , _IVm7th , and _Vm7th chords. In this case as well, the chord converted to the frequency display is I _7th , IV _7th , V _7th ,
If any of the chords I _m7th , IV _m7th , V _m7th
Based on the determination of "YES" in Steps 715 and 716, the processing of Steps 714 and 712 sets the modality data SCALE to data representing the Minables modality and the Bruce modality, respectively. Further, the chord converted to the frequency display is I _7th , I 7
If none of the chords of V _7th , V _7th , I _m7th , IV _m7th , and V _m7th correspond to any of the chords, `` N
If the determination is "O", the program proceeds to step 707, and the trajectory is determined by the processing including steps 707 to 709.

With the processing of steps 710 to 716, for blues, a more appropriate method is determined, and at the same time, even if the processing does not determine the blues method or the minables method, the above-described processing of steps 707 to 709 is performed. Determines the appropriate mode.

As described above, when the rhythm interrupt signal RINT from the tempo oscillator 70 arrives at the CPU 82 which is executing the main program including the processing for determining the chord, the key and the melody according to the key pressed on the keyboard 10 and other processing and its subroutines. ,
The CPU 82 controls the generation of percussion sounds and accompaniment sounds by executing a rhythm interruption program corresponding to the flowchart of FIG. 12 every time the interruption signal RINT arrives. Therefore, the rhythm interruption program will be described below.

Rhythm interrupt program The execution of this rhythm interrupt program is started at step 800 in FIG.
It is determined whether or not RUN is “1”. In such a case, if the rhythm run flag RUN has been set to “1” by the processing of step 125 (the main program in FIG. 5), “YES” is determined in step 801 and the program proceeds to step
Proceeding to 802 or later, the generation of percussion sounds and accompaniment sounds is controlled, and if the flag RUN is “0”, the generation of the percussion sounds and accompaniment sounds is not controlled, and in step 817 the rhythm interruption program is executed. Execution is terminated.

In step 802, a rhythm pattern memory is stored according to the rhythm type data RHY and the tempo count data TCNT.
92, all percussion sound data PI corresponding to the selected rhythm represented by the rhythm type data RHY and related to the timing represented by the tempo count data TCNT.
TD ₁ and percussion sound data PITD ₂ are stored in rhythm pattern memory 92
The percussion instrument sound data PITD ₁ and the percussion instrument sound data PITD ₂ are read out from the
Supplied to 1. As a result, the percussion instrument sound signal generation circuit 61 forms a tone signal relating to the percussion instrument represented by the supplied percussion instrument sound data PITD ₁ , percussion instrument sound data PITD _2, etc., and supplies it to the sound system 63. Percussion sounds are pronounced. The rhythm pattern memory
If the data read from 92 indicates NOP, the data is not output to the percussion instrument sound signal generation circuit 61, and the generation of the percussion instrument sound signal is not controlled.

After the processing of step 802, the program proceeds to step 8
In step 803, the variable i is set to “1”. This variable i specifies the number of accompaniment sound sequences, that is, the accompaniment pattern memories 93-1 to 93-n.
Varies over time. Next, in step 804, the rhythm type data RHY, the winding data SCALE, and the tempo count data
The accompaniment pattern memory 93-i of the i-th sequence is referred to in accordance with the TCNT, and corresponds to the selected rhythm and the melody represented by the rhythm type data RHY and the melody data SCALE, and the accompaniment relating to the timing played by the tempo count data TCNT. The pattern data is read. The type of the read accompaniment pattern data is determined in steps 805 and 806.

That is, if the read accompaniment pattern data relates to the key-on data KON and the pitch data PINT, the determination in step 805 is “NO” and the determination in step 806 is “YES”, and the program step 80
Proceed to 7. In step 807, it is determined whether or not the key pressed chord data DPCHD indicates that chords are not established. In this case, if the key pressed chord data DPCHD does not indicate that the chord is not established, “NO” is determined in step 807, and the root note RO of the key pressed chord data DPCHD is determined in step 808.
The pitch data ROOT + PINT obtained by adding the OT and the read pitch data PINT and the key-on data KON are supplied to the i-th stream of the accompaniment sound signal generation circuit 62 via the bus 50. As a result, the i-th sequence tone signal forming channel in the accompaniment tone signal generating circuit 62 forms a tone signal having a pitch corresponding to the supplied pitch data ROOT + PINT and supplies the tone signal to the sound system 43. From the key press chord data DPCHD
Arpeggio, bass,
Out of the n pieces of accompaniment sounds such as chord sounds, a musical tone related to the i-th sequence accompaniment sound is generated.

On the other hand, if "NO" in step 807, that is, if it is determined that the key pressed chord data DPCHD indicates that chords are not established, in step 809, the presence or absence of chord data in the chord table 83g is generated. In this case, if there is chord data in the same table 83g, "YES" is determined in step 809, and the latest chord data in the chord table 83g specified by the current table address CTAD is read out in step 810. And the chord data is depressed chord data DPCH
Instead of D, it is used to generate an accompaniment sound in the same manner as in the processing of step 808. That is, the root RO of the chord data
The pitch data POOT + PINT and the key-on data KON added to the OT, the pitch data PINT read from the accompaniment pattern memory 93-i, and the key-on data KON are supplied to the i-th sequence of the accompaniment sound signal generation circuit 62 via the bus 50. Accordingly, an appropriate accompaniment sound can be obtained even if no chord is detected from the current key depression. If the chord data is not in the chord table 83g immediately after the start of the performance, "NO" is determined in step 809, and the program proceeds to step 812. In this case, the i-th sequence accompaniment sound is not generated.

When the description returns to the above-described processing of steps 805 and 806, if the accompaniment pattern data read from the accompaniment pattern memory 93-i by the processing of step 804 is the key-off data KOF, “NO” is determined in steps 805 and 806, respectively. Is determined, and in step 811 the key-off data KOF
Is supplied to the i-th stream of the accompaniment sound signal generation circuit 62 via the bus 50. As a result, the i-th musical tone signal forming channel in the accompaniment sound signal generating circuit 62 attenuates the i-th musical accompaniment sound signal based on the supplied key-off data KOF, and then stops its generation. As a result, the i-th sequence accompaniment sound from the sound system 63 gradually disappears. After the processing in step 811, the program proceeds to step 812.

Further, the accompaniment pattern data read from the accompaniment pattern memory 93-i by the processing of the step 804 is
If NOP is indicated, “YES” is determined in step 805, and the program proceeds directly to step 812. In such a case, the processing related to the accompaniment sound is not performed.

After the processing of the i-th series as described above, “1” is added to the variable i in step 812, and while the variable i after the addition is equal to or smaller than n, “NO” is determined in step 813, and The program returns to step 804 and returns to step 8
Processing of an accompaniment sound generation control routine consisting of 04 to 811 is performed. Thereby, generation of all the accompaniment sounds of the first to n-th series is controlled.

During the circulation process consisting of steps 804 to 813, the variable i
Is larger than n, it is determined as "YES" in step 813, and the program proceeds to a tempo count data TCNT update processing routine including steps 814 to 817. That is, "1" is added to the tempo count data TCNT in step 814, and the data TCNT is advanced.
At 815, the advanced tempo count data TCNT
2 "has been reached. If the tempo count data TCNT is less than “32”, “NO” is determined in step 815, and the execution of the rhythm interrupt program is terminated in step 817. When the tempo count data TCNT reaches “32”, “YE
Is determined to be "S", and the data TCNT is "0" in step 816.
After that, the execution of the rhythm interrupt program is terminated in step 817.

As can be understood from the above description of operation, according to the above embodiment, a musically appropriate chord, key and key are automatically detected in response to key depression on the keyboard 10, and an appropriate pitch based on the detection is detected. Is automatically generated according to the rhythm, so that a musically advanced automatic accompaniment sound can be obtained. In the above embodiment, in addition to the means for automatically determining the key according to the chord performance information, the key is manually determined according to the operation of the major operator 22, the minor operator 23 and the keyboard 10. Since the means is provided, if the user knows the key at the start of the music piece, the key can be designated from the beginning of the music piece.
In such a case, the means for automatically determining the key functions to automatically determine the modulation during the performance.

 The above embodiment may be modified as follows.

(1) In the above embodiment, when the key is determined when the rhythm type is other than blues, steps 604 to 604 in FIG. 10A are performed.
At 610, a specific chord progression is detected and two kinds of keys are assumed.
At steps 612 to 614, the harmony of the past eight chords is checked by comparing the total value of the tension levels of the past eight chords with respect to the two keys, and finally the key is determined. If the key cannot be determined, the suitability of all the key depression sounds corresponding to the past eight chords to the above-mentioned two tones is determined in steps 617 to 619 to finally determine the key. However, if a slight decrease in musicality is allowed for cost reduction, steps 612 to 614,617 are performed.
619 may be omitted and the key corresponding to the root ROOT may be determined by the processing of only steps 604 to 610. Further, the steps 612 to 614 or steps 617 to 619
May be omitted. Even with these, simple songs can be handled sufficiently.

Also, in the above embodiment, the step
In 604 to 610, the key is determined based on the progression of two consecutive chords, but the key may be determined based on the progression of three or more continuous chords. In such cases,
For chords newly detected from the chord table 83g (FIG. 2F), three or more consecutive chord data may be read out in the past and compared with predetermined chord progression conditions.

(2) In the above embodiment, the number of tension sounds TENSU is determined by the first and second chord detection routines (FIGS. 8 and 9C).
Although the minimum chord is finally determined as the determined chord, and if there is more than one of the minimum number of tension sounds TENSU, the chord including the lowest tension tone number LTNO among them is finally determined as the determined chord, Instead of this determination method, the chord having the smallest total value of the tension tone numbers LTNO for all tension tones for each chord may be finally determined as the determined chord. In such a case, in steps 341 to 349 of FIG. 7, the number of tension sounds TENSU and the minimum tension sound number LTNO are stored in the chord detection buffer register 83c.
, The total value of the tension tone numbers TNO of all tension tones for each detected chord is calculated, and the total value is written in the chord detection buffer register 83c, and the first and second chord detections are performed. In the routine, the one with the smallest total value may be finally determined as the determined chord.

In the above embodiment, step 321 in FIG.
After writing information about all possible chords in the chord detection buffer register 83c by a cyclic process including steps 329 to 329 and steps 341 to 349, the first chord detection routine of FIG. 8 and FIGS. 9A to 9C In the second chord detection routine, the most probable chord is finally determined as the determined chord while reading the information about all the chords. However, only the information about one chord is stored in the chord detection buffer register 83c. Each time a possible chord is detected by the processing of steps 310 to 315 in FIG. 7, the information in the chord detection buffer register 83c and the information on the chord newly determined this time are stored. By using the same method as that of the first and second chord detection routines to update the information in the chord detection buffer register. When the processing relating to the chord finally detected by the processing of steps 310 to 315 is completed, a successive approximation method may be employed in which the final chord is automatically and finally determined. By doing so, the capacity of the chord detection buffer register 83c can be reduced.

(3) In the above embodiment, accompaniment pattern memories of a plurality of sequences are provided corresponding to each rhythm type and each melody.
93-1, 93-2 ... 93-n are provided and each memory 93
-1,93-2... 93-n store the pitch data PINT corresponding to the semitone interval difference from the fundamental tone of the various modalities, but instead of the pitch data PINT, frequency data (No.
The “1”, “2”,... In FIG.
-1,93-2... 93-n and a common accompaniment pattern memory is used for various types of melody, and a plurality of series of accompaniment pattern memories 93-1 and 93-only are used for each rhythm type. 2 ... 93-n may be provided. In such a case, a frequency-pitch table for converting the frequency data into pitch data PINT (semitone interval difference from the fundamental tone of various modes) as in the above embodiment is separately provided, and the rhythm type data RHY is set in step 804 in FIG. And reading the accompaniment pattern data according to the tempo count data TCNT, and if the read accompaniment pattern data is the frequency data, after changing the frequency data to the pitch data PINT according to the modal data SCALE in steps 808 and 810, The addition process of the converted pitch data PINT and the root data ROOT may be performed. For example, if the frequency data read from the accompaniment pattern memories 93-1, 93-2,... 93-n is "3", the frequency data "3" if the mode data SCALE indicates the ionian mode. Is "4"
The frequency data "3" is converted to "3" if the modal data SCALE represents the Dorian modality (see FIG. 3G). Thereby, the accompaniment pattern memory 93 can be configured with a small capacity.

(4) In the above embodiment, when the rhythm type is other than blues, the key is determined for each major and minor by detecting a specific chord progression, and when the rhythm type is blues, the key is determined from a predetermined past. To determine the key for each major and minor by detecting the presence or absence of a specific chord up to, that is, to change the key determination method for the major and minor in accordance with only two types of music, The key determination method for each music style is further subdivided, and according to the rhythm type specified by the rhythm selection operator group 31, a specific chord progression or generation of a specific chord different from the above-described embodiment is performed for each rhythm type. The key may be determined by detecting the presence or absence.

(5) In the above embodiment, an example in which the present invention is applied to an electronic musical instrument having the keyboard 10 has been described. However, the present invention does not include the keyboard 10 and externally stores note name information corresponding to key depression of each key. The present invention can also be applied to a device having an input interface for inputting a password. In such a case, the input interface is supplied almost simultaneously from another electronic musical instrument or a device having only a keyboard, and inputs a plurality of note name information specifying a chord one after another. It is only necessary to determine whether or not there is note name information in the input interface to which the note name information is input, and to control in step 104 to take in the note name information from the input interface. This makes it possible to form an optimal accompaniment sound only by inputting key information (note name information) from a device having only other musical instruments and a keyboard.

[Brief description of the drawings]

FIG. 1 is an overall block diagram of an electronic musical instrument according to an embodiment of the present invention, FIGS. 2A to 2I are detailed views of various tables and registers in a working memory of FIG. 1, FIG. 3A, FIG.
FIGS. 3D, 3E and 3F are detailed diagrams of various detection tables in FIG. 1, FIG. 3B is a musical note diagram showing an example of a detected chord, and FIG. 4A is a detailed view of the rhythm pattern memory of FIG. 1, FIG. 4B is a detailed view of the accompaniment pattern memory of FIG. 1, and FIGS. 5 to 12 are executed by the microcomputer of FIG. It is a flowchart of a program. Explanation of reference numerals 10 ... keyboard, 20 ... key setting operation panel section, 30 ... rhythm control operation panel section, 61 ... percussion instrument sound signal generation circuit, 62 ...
... accompaniment sound signal generation circuit, 70 ... tempo oscillator, 80 ... microcomputer, 81 ... program memory, 82 ...
CPU, 83: working memory, 83a: key press buffer register, 83b: key press key flag buffer register, 8
3c: Chord detection buffer register, 83d: Rotation register, 83e: Root note counter, 83f: Key depression key flag table, 83g: Chord table, 83h: Blues table, 83i: Tone flag table, 91 ... Various detection tables, 91a... Chord constituent sound table, 91b... Chord tension table, 91c... Primary / cadence chord table, 91d.
Rotation table, 92: Rhythm pattern memory, 93: Accompaniment pattern memory.

Claims (7)

(57) [Claims] 1. A chord detecting device for detecting a chord based on a combination state of a plurality of note names each representing a note name constituting a musical scale. A chord extracting means for extracting a plurality of detected chords by detecting a chord in accordance with a combination state of a plurality of tone names respectively specified by, from among a plurality of detected chords extracted by the chord extracting means, A chord testing means for determining a detected chord having a low degree of tension relating to the detected chord and being a tension tone related to the tension sound included in the designated plurality of tone names as a determined chord. Chord detector. 2. A root setting means for setting each of the plurality of designated tone names as a root, wherein the chord extracting means comprises: a root sound for each of the root sounds set by the root setting means; The chord detection device according to claim 1, further comprising: a determination unit configured to determine whether or not a note name having a predetermined frequency relationship exists in the plurality of designated note names. 3. The chord detecting device according to claim 2, wherein the note names in said predetermined frequency function are basic constituent sounds of chords, and are stored in advance for each chord. 4. The chord determining means, wherein the chord having the least number of tension tones included in the plurality of designated tone names is selected from the plurality of detected chords extracted by the chord extracting means. 2. The chord detecting device according to claim 1, wherein the chord detecting device is configured to determine a chord having a low degree of tension related to a tension sound. 5. The chord detecting device according to claim 1, wherein the tension sound is stored in advance for each of various chords. 6. The chord determining means, wherein a chord including a tension tone having the smallest tension level with respect to the detected chord among a plurality of detection chords extracted by the chord extraction means has a lower tension level with respect to the tension tone. 2. The chord detecting device according to claim 1, wherein said chord detecting device is constituted by means for determining a chord. 7. The tension sound is stored in advance for each chord, and the degree of tension of each tension sound is represented by a numerical value and stored in advance for each chord. The chord detection device according to item 1.