JPH0315199B2 - - Google Patents

Description

[Detailed description of the invention] The invention will be explained in the following order.

Industrial application field Overview of the invention Prior art Problems to be solved by the invention and means for solving them Effects of the invention Examples Embodiments Explanation of the configuration of the electronic musical instrument shown in Figure 1 Description of the operation of the electronic musical instrument shown in Figure 1 1 Main processing 2 Keys Processing 3 Chord detection processing 4 Tempo interruption processing 5 Transposition processing 6 Tempo interruption processing (continued) Modification of the embodiment [Field of industrial application] The present invention relates to an electronic musical instrument having an automatic accompaniment function, and in particular, to an electronic musical instrument having an automatic accompaniment function. Chord (chord) to be input
To provide an electronic musical instrument that limits the change in chord types caused by variations in key release when automatically playing accompaniment according to information from directly changing the automatic accompaniment sound, and adjusts responsiveness to key operations to human senses.

[Summary of the Invention] The present invention provides an electronic musical instrument with an automatic accompaniment device that performs automatic accompaniment according to chord information input from a keyboard, and when a new key is released, the key press state after the key release is changed. By changing the contents of the automatic accompaniment or restricting the pronunciation based on this, the responsiveness to changes in chord type due to variations in key release can be adjusted to human senses.

[Prior Art] As a conventional electronic musical instrument with an automatic accompaniment device, the root note and chord type of the bass note to be played are detected from the pressed state of the lower keyboard, and the bass note is played according to these root note and chord type. There is a so-called finger mode in which the sound is automatically generated, and the root note of the bass note to be played is detected from the key press state of the pedal keyboard, and the chord type of the bass note is detected from the key press state of the lower keyboard. Automatically generate bass notes according to root note and chord type,
There are known devices that have an automatic accompaniment mode, such as a so-called custom mode. In addition, the chord types can be determined extremely quickly by directly referring to the chord type table using the 12-bit data indicating the key press status, in which each bit corresponds one-to-one to each note of C, C#, ..., B, as an address. An electronic musical instrument (see Japanese Patent Application Laid-open No. 196593/1983) that can be obtained from

Incidentally, in such an electronic musical instrument, the type of chord is sequentially detected according to the state of key depression, and the accompaniment tone to be sounded is selected according to the type of chord. For this reason, chords are detected in response to unintentional variations by the performer that occur when keys are released, and accompaniment tones corresponding to the chords are generated. Therefore, unnecessary musical sounds are generated, which are not only unpleasant to the ears during performance, but also impair the performance effect in some cases. For example, when the keys corresponding to the C, E, and G notes are pressed down and the device detects the C major and produces the root note, that is, the C note as the bass note, the performer releases the three notes at the same time. Assuming that you actually operated in the order of C → E → G, the device will change the pressed state of keys E, G after releasing the C note.
Detects the chord "E major" and produces the E note as the base note, followed by the key pressed state G after the E note is released.
Detects the chord "G major" and produces a G note as a bass note. In other words, the bass note is momentarily pronounced as C→E→G and then turned off, and regardless of the performer's intention to turn off the C note, unnecessary E, The G sound is included and becomes harsh.

[Problems to be Solved by the Invention and Means for Solving the Problems] An object of the present invention is to prevent an adverse effect on the automatic accompaniment sound due to variations in key release in an electronic musical instrument equipped with an automatic accompaniment device.

In order to achieve the above object, the present invention provides an electronic musical instrument with an automatic accompaniment device that detects chord types (chord types and root notes) based on key depression states on a keyboard and produces accompaniment tones according to the chord types. Based on the number of pressed keys after the key is released, when the number of pressed keys is less than a predetermined number, the sound generation state of the accompaniment sound, for example, whether or not to change the accompaniment chord, or whether or not to emit the accompaniment sound, is controlled.

In one aspect of the present invention, erroneous detection of a chord type due to variations in key release in finger mode is prevented as described below.

When a key is released, for example, if the number of pressed keys after the key is released is 2 or less, the chord type is not detected, and a new chord type is detected only when the number of pressed keys after the key is released is 3 or more. Let's do it.

[Effects of the Invention] As described above, according to the present invention, a certain limit is set on the pronunciation of automatic accompaniment tones based on the number of keys pressed after the key is released, which eliminates the drawbacks of conventional automatic accompaniment devices. Unnecessary pronunciations due to erroneous detection of chord types based on variations in key presses can be significantly suppressed.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block circuit configuration of an electronic musical instrument according to an embodiment of the present invention.

Explanation of the structure of the electronic musical instrument shown in FIG. 1 In FIG. 1, a keyboard circuit 11 detects a pressed key on a keyboard (not shown) and generates key information (key code) representing the pressed key. The switch group 12 includes various operation switches arranged on an operation panel (not shown), such as a start/stop switch for controlling the start and stop of automatic accompaniment, an accompaniment tone memory on/off switch, and the like.

The electronic musical instrument shown in FIG. In addition to switch group 12, program memory 15, working memory 16, pattern memory 17, tempo oscillator 18 and tone generator (TG)
19 mag is connected. And CPU13 is
By taking in the key code output from the keyboard circuit 11 and switch information from the switch group 12, and performing arithmetic processing based on these information, predetermined musical tone information (information such as start of sound, stop of sound, pitch, timbre, etc.) It controls the overall operation of this electronic musical instrument, such as forming musical tone information and sending this musical tone information to the tone generator 19.

The program memory 15 is composed of a read-only memory (ROM), and stores a control program for the CPU 13.

The working memory 16 is for temporarily storing various data generated when the CPU 13 executes the control program, and is made up of, for example, random access memory (RAM), and stores the following various flags, registers, buffers, etc. It is provided.

RHY: Rhythm run flag Indicates whether the rhythm is running (“1”) or stopped (“0”) MEM: Accompaniment sound memory flag Accompaniment sound memory on (regarded as being pressed even if the key is released) (“1”) ”) or (“0”).

TCL: Tempo counter Tempo clock number 0 to 63, indicating the current timing within a rhythm pattern (for example, 2 bars).

RHYNO: Rhythm type register KCOUT: Key code output buffer Stores the key code sent to TG19 MINKC: Lowest note key code buffer Stores the key code indicating the lowest note being pressed TEST: Temporary buffer For transposition calculation KEYCOD: Key code buffer This is a buffer in the format shown in FIG. 2a for temporarily storing key events read from the keyboard circuit 11 when an event due to a key press operation occurs. That is, the most significant bit (MSB) stores an on/off flag indicating whether the key event is a key press or a key release, and the lower 7 bits store a key code. This key code has an octave code OCT in the upper 3 bits of the 7 bits above.
And the lower 4 bits are the note code NOTE.
Store. Note codes 0 to 11 are made to correspond to pitch names C, C#, . . . , A#, B, respectively.

KEYBUF: Stores one or more key codes corresponding to the currently pressed key. The data format per note is the same as the key code buffer KEYCOD (see Figure 2b). Here, the same number of sound generation channels as provided in TG19 are prepared.

NOTEREG: Note code register This is a 12-bit register that indicates the key pressed status on the accompaniment keyboard.As shown in Figure 2c, each bit is assigned one to one for each note name of C, C#, ..., A#, B. The name of the note being pressed is indicated by "1".

ROOT: Root note register CHDTYP: Chord type register In the following explanation, each register, etc. and its contents will be represented by the same label name. For example, both the keypad and its contents are
It becomes KEYBUF.

The pattern memory 17 is a pattern table.
It is a read-only memory (ROM) in which PTNTBL, code table CHDTBL, etc. are provided.

The pattern table PTNTBL stores automatic accompaniment pattern information for the number of rhythm patterns x number of chord types x simultaneous pronunciation series. here,
It is possible to simultaneously produce one series of auto bass and four series (up to four notes can be produced at the same time) of multiple note arpeggio, and the number of simultaneously produced series is five.
As shown in Figure 3a, each automatic accompaniment pattern data includes, for each series, the required number of words (1 word = 2 bytes) of event data representing the automatic accompaniment pattern, and 1 word representing the end of the automatic accompaniment pattern. It consists of a byte end code, for example FFFFH (in hexadecimal). Furthermore, as shown in Fig. 3b, one event is stored in the lower 6 bits of the first byte of the 2 bytes as the tempo clock TCL (0 to 0).
63) is stored, and the content of the event is stored in the second byte. The format of this second byte of event data is based on the key buffer in the working memory 16 mentioned above.
Same as KEYBUF etc. In other words, the most significant 8th bit (MSB) of the 2nd byte is an on/off flag indicating whether the event is a key-on or key-off, and the lower 7 bits are the key code to be sounded or stopped. It is.
Also, this key code is an octave code
OCT (7th to 5th 3 bits) and note code
Note (4th bit to LSB 4 bits) is stored separately. Furthermore, note codes 0 to 11 are made to correspond to pitch names C, C#, . . . , A#, B, respectively, similar to the above key buffer KEYBUF. Note that this rhythm pattern is prepared only for those whose root note is C. Furthermore, the upper two bits of the first byte are not used.

The chord table CHDTBL is used to generate chord type (chord type and root note name) information from key press information, and as shown in Figure 3c, the 12-bit data in the note code register NOTEREG is used as an address. Code type this as
Consists of a 4096 byte memory area that converts to CHDTYP and root name ROOT. code type
The correspondence between CHDTYP and root name ROOT and data values is shown in d and e of FIG. 3, respectively. Chord type CHDTYP is 0 to stop accompaniment, 1 to 8 to be major (M), minor m,..., susfour sus4
It corresponds to each. 9 indicates that the code is not established. For the root note name ROOT, 0 to 11 are the same as the note codes described above, and 12 indicates that the lowest note being pressed is selected.

The tempo oscillator 18 is composed of, for example, a variable frequency oscillator or a fixed frequency oscillator and a frequency divider with a variable division ratio that divides the output of this oscillator to create a tempo clock. Generates a 1/8 cycle tempo clock. The period of the tempo clock is varied by a tempo setter (not shown), such as a polyurethane or a switch, located on the operation surface.

The tone generator 19 has four channels for forming chord and arpeggitic chord sounds, one channel for forming bass sounds, and a plurality of channels, for example, five channels, for forming melody sounds. A musical tone (chord tone, bass tone, and melody tone) signal corresponding to the given musical tone information is formed. This musical tone signal is converted into sound and produced by a sound system including an amplifier 20, a speaker 21, and the like.

Explanation of the operation of the electronic musical instrument shown in FIG. 1 Next, the operation of this electronic musical instrument will be explained with reference to the flowcharts shown in FIGS. 4 to 8.

1 Main Processing Referring to FIG. 4, when the electronic musical instrument is powered on, the CPU 13 starts operating according to the control program stored in the program memory 15 (step 100). In step 101, each flag RHY, MEM, tempo counter TCL, each buffer KCOUT, MINKC, TEST, KEYCOD,
KEYBUF and register RHYNO,
After initializing the entire circuit, such as clearing NOTEREG, ROOT, and CHDTYP, the main processing routine processing operations consisting of steps 110 to 140 and step 200 are executed.

That is, in step 110, the memory switches of switch group 12 are tested. When the state of this memory switch changes, it is determined in step 111 whether or not the state change is a change to an on state (on event). If it is an on event, a memory flag MEM in the working memory 16 is set in step 112. On the other hand, when it is not an on-event,
In other words, if it is an off event, the above flag MEM is reset in step 113, and then step 1
At step 14, the on/off bit set in the most significant (MSB) of each byte of the key buffer KEYBUF in the memory 16 is checked. If all on/off bits are “0”, all keys have been released (all keys off), so step 11
After clearing the root note register ROOT and chord type register CHDTYP in the memory 16 in step 5, if any one of these on/off bits is "1", that is, if at least one key remains pressed. If so, proceed directly to step 120.
Note that if no event has occurred in the memory switch in step 110, the process is directly executed in step 12.
Go to 0.

In step 120, the rhythm switches of switch group 12 are tested. If an event occurs in this rhythm switch, it is determined in step 121 whether it is an on event or an off event, and if it is an on event, the rhythm run flag RHY in the memory 16 is set in step 122. ,
On the other hand, if it is an off event, the flag RHY is reset in step 123, or directly from step 120 if no event has occurred.
Proceed to step 130.

In steps 130 and 131, other switches such as the rhythm selection switch of the switch group 12 are checked, and various processes corresponding to events occurring with respect to these switches are performed.

In step 140, the output of the keyboard circuit 11 is checked to determine whether the state of any of the keys has changed (a key event has occurred), and if a key event has occurred, the key processing shown in FIG. 5 is executed.

2 Key Processing Referring to FIG. 5, in step 201, the key code of the operated key is read from the keyboard circuit 11 and stored in the key code buffer KEYCOD. Subsequently, in step 202, it is determined whether or not this key code was generated by an operation on the accompaniment keyboard (lower keyboard). If the above key code is not from the accompaniment keyboard, it is due to the operation of the melody keyboard (upper keyboard), etc., so proceed to step 2.
03, after controlling the tone generator 19 with the pitch (key code) corresponding to the key operation, that is, after performing the process of generating or stopping the sound according to the key operation, the main process (step 11) of FIG.
Return to 0). On the other hand, if the key code is due to an operation on the accompaniment keyboard, the process moves to step 204, where it is determined whether the event is a key press. If the key is pressed, it is checked in step 205 whether there is space in the key buffer KEYBUF in the memory 16. If there is no free space in the buffer KEYBUF, the key press is ignored and the process returns to the main process (step 110) in FIG. On the other hand, if there is space, in step 206 the key code in the key code buffer KEYCOD is stored in the empty space in this buffer KEYBUF, and in step 207 the bit in the note code register NOTEREG corresponding to the note name NOTE of this key code is stored. is set to “1”,
Furthermore, code detection processing (step 30) to be described later
After executing step 0), the process returns to the main process (step 110) in FIG.

In step 204, if the key event is not a key press but a key release operation, in step 210 the key buffer KEYBUF is turned on/off.
If the off flag ON/OFF is "1" (key being pressed) and the lower 7 bits of the key code KEYCOD are equal to the key released, the flag ON/OFF is set to "0" and is further stored in the key buffer KEYBUF in step 211. The on/off flag of the data set is “1” and the key code
Search for the same KEYCOD and note name NOTE. If there is no note with the same note name NOTE, in step 212 the note code register corresponding to the note name NOTE of the above key code KEYCOD is entered.
Reset the NOTEREG bits. If the flag ON/OFF is "1" and the released key code KEYCOD is equal to the data in the lower 7 bits, then the key with the same note name in another octave is being pressed. note code register
The contents of NOTEREG are not changed. In other words, the process of step 212 is skipped.

Furthermore, in step 220, it is determined whether the accompaniment tone memory flag MEM in the memory 16 is "0" and the flag in the buffer KEYBUF.
It is determined whether ON/OFF is "1", that is, whether there are three or more keys being pressed on the keyboard. If the flag MEM is "0" and three or more keys are being pressed, the code detection process (step 30
After executing step 0), the process returns to the main process (step 110) in FIG.

This electronic musical instrument detects chord types according to key press operations such as in finger chord mode, and prevents incorrect detection of chord types due to variations in key release when automatic accompaniment is performed according to the chord types. Here, if the number of keys currently being pressed is less than three and one or more, the current key release operation (key-off event) is considered to be due to key release variation. Therefore, in step 220, first, the memory 16
If the accompaniment tone memory flag MEM within is "0", it is determined that the mode is for detecting chord types according to key press operations. Next, if the number of flags ON/OFF is "1" is less than 3, in step 221, the number of flags ON/OFF "1" is 1.
Determine whether there are more than 1. If there is one or more pressed keys in step 221, it is determined that the current key-off event is due to variations in key release, and in order to prevent the above-mentioned erroneous detection, code detection is not performed and the main processing in FIG. 4 (step 110) is performed. ). On the other hand, if it is determined in step 221 that there are no keys being pressed (all keys off), step 222
After clearing the root note register ROOT and chord type register CHDTYP in the memory 16, the process returns to the main process (step 110) in FIG.

3. Code Detection Processing FIG. 6 shows the code detection processing subroutine of step 300 in FIG. In this code detection process, first, in step 301, the code data table is set using the 12-bit data of the note code register NOTEREG in the memory 16 as an address.
Refer to CHDTBL and corresponding code type
Read the data of CHDTYP and root name ROOT. These data are stored in registers in memory 16.
Store it in CHDTYP and ROOT. In addition,
When the code is not established, the code type data
CHDTYP is 9 and root name data ROOT is 12.

In the next step 302, it is determined whether the chord is established based on the chord type data CHDTYP. If the code fails (code type
If CHDTYP=9), the code type CHDTYP in the memory 16 is set to 1 (major) in step 303, and on the other hand, if the code is established (code type CHDTYP≠9), the process directly proceeds to step 304.

In step 304, the root note name data ROOT is
12 (lowest note). If, 12
If so, in step 305 the key buffer is
Search for the lowest note from KEYBUF and store the key code in the lowest note buffer MINKC, Step 3
After storing the lower 4 bits of this lowest note, ie the note code, in the root note name register ROOT in step 06,
The process returns to the main process (step 110) in FIG.
On the other hand, in step 304, the root note name data is
If ROOT is not 12, the process directly returns to the main process (step 110) in FIG.

4 Tempo Interrupt Processing As mentioned above, in the electronic musical instrument shown in FIG. 1, the following interrupt processing (step 400) is performed using the tempo clock generated from the tempo oscillator 18 as an interrupt signal.
Execute. In FIG. 7, in step 401, the rhythm run flag RHY is checked. if,
If the flag RHY is "0", the automatic rhythm and accompaniment are not currently being played, so the tempo counter TCL is cleared (step 402).
After that, the routine returns to the one from which the interrupt was canceled.

On the other hand, as a result of the inspection in step 401, the flag
If RHY is "1", that is, if the automatic rhythm and accompaniment are currently being played, the process moves to step 403. In step 403, rhythm tone generation processing is performed at a timing corresponding to the count value of the tempo counter TCL. In the following step 404, the chord type CHDTYP in the memory 16 is set to 0, indicating that the sound generation is stopped.
Determine whether or not. If the pronunciation is stopped,
The interrupt is canceled without performing steps 405-414 and step 500, and the process returns to the original routine.

On the other hand, if it is determined in step 404 that the sound generation is not stopped (data CHDTYP=0), the process advances from step 404 to step 405. Step 40
5, the event data (on/off flag ON/OFF and key code
KC) is read out, and if the on/off flag ON/OFF is "1", the key code KC is stored in the buffer KCOUT in the memory 16, and then the process proceeds to step 500.
The process proceeds to the transposition processing routine (FIG. 8).

5 Transposition processing In this electronic musical instrument, the pattern table
PTNTBL was created with the root note ROOT as C note. Therefore, if the root note ROOT is a note other than the C note, it is necessary to transpose the accompaniment note to be produced by the pitch of the root note.

Referring to FIG. 8, in step 501, the lower 4 bits of the buffer KCOUT, that is, the note code NOTE part, that is, the pitch from the C note, is added to the root note data ROOT, and the data is added to the root note data ROOT.
Store in TEST. Subsequently, in step 502, it is determined whether the added data TEST is 12 or more. If it is less than 12, in step 503 this addition data TEST is stored as note code data in the lower 4 bits of the buffer KCOUT, and then the tempo interrupt routine (step 4
Return to 10). On the other hand, the above addition data TEST is 12
If it is above, the above addition data TEST indicates the note name one octave higher, so in step 504, the value obtained by subtracting 12 from the above addition data TEST is calculated as the note code.
After storing it as a NOTE in the lower 4 bits of the buffer KCOUT (step 504) and adding 1 to the upper bit (octave code OCT) (step 505), the process returns to the tempo interrupt routine (step 410) of FIG.

6. Tempo interrupt processing (continued) At step 410, the key code stored in the buffer KCOUT is sent to the tone generator 19. The tone generator 19 generates an accompaniment tone having the pitch of this key code. Step 4
In step 11, it is determined whether there is event data with the same timing in other sound generation series. if,
If there is event data with the same timing, the process returns to step 405 and repeats the above-mentioned process; otherwise, the process proceeds to step 412.

In step 412, the tempo counter TCL is incremented, and in step 413, it is determined whether the count value of the counter TCL is 64 or not. If it is not 64, the interrupt is canceled and the original routine returns. On the other hand, if the count value of counter TCL is 64,
After clearing the counter TCL in step 414,
Release the interrupt and return to the original routine.

[Modifications of Embodiments] The above are embodiments of the present invention, but the present invention is not limited to the above-described embodiments and can be implemented with appropriate modifications. For example, the above-described embodiment may be provided with an ABC (auto bass chord) on/off function, and melody key processing may be performed using accompaniment keys. Furthermore, in the above embodiment, the chord type and root note are detected for each pressed accompaniment key, and musical tones are controlled based on these, but it is also easy to provide a group of tones that are produced by the key code of each pressed key. . Further, in the above description, when the chord type is not established, the accompaniment tone is played in place of the major chord, but it may be replaced with another type of chord such as a minor chord.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an electronic musical instrument according to an embodiment of the present invention, FIG. 2 is a format diagram of buffers and registers set in the working memory of the musical instrument of FIG. 1, and FIG. The format diagrams of various tables stored in the pattern memory of the musical instrument shown in FIG. 1, and FIGS. 4 to 8 are flowcharts for explaining the operation of the musical instrument shown in FIG. 11: Keyboard circuit, 12: Switch group, 13:
CPU, 15: Program memory, 16: Working memory, 17: Pattern memory, 18: Tempo oscillator, 19: Tone generator.

Claims (1)

[Scope of Claims] 1. A chord type detection means for detecting a chord type based on a key depression state on a keyboard, and an accompaniment tone formation for forming a predetermined automatic accompaniment tone based on the chord type information output from the chord type detection means. means for detecting a key release on the keyboard and, based on the number of keys pressed after the key is released, restricting the change or use of chord type information serving as a reference for the automatic accompaniment tone formation when the number of keys pressed is less than a predetermined number; An electronic musical instrument with an automatic accompaniment device, characterized in that it has an accompaniment control means. 2. The automatic accompaniment device according to claim 1, wherein the accompaniment control means restricts the change or use of the chord type information when the number of pressed keys on the keyboard after the key release detection reaches 2 or 1. electronic musical instrument. 3. According to claim 1 or 2, the accompaniment control means performs the restriction by prohibiting the chord type detection operation of the chord type detection means or the output or output change operation of the chord type information. An electronic musical instrument with an automatic accompaniment device. 4. The electronic musical instrument with an automatic accompaniment device according to claim 1, 2 or 3, wherein the accompaniment control means stops generating the accompaniment sound when the number of pressed keys on the keyboard after the key release detection reaches 0. .