RU2754425C1 - Intelligent physical midi interface - Google Patents

Abstract

FIELD: musical instruments.SUBSTANCE: invention relates to the field of electronic musical instruments, in particular, to apparatuses for learning to play a musical instrument, and constitutes a hardware and software apparatus. The intelligent physical MIDI interface is configured to be connected to a MIDI keyboard and synthesiser. The interface comprises a microcontroller, a non-volatile memory, a control apparatus, a signal generator for the MIDI input, and a signal generator for the MIDI output. The non-volatile memory is configured to save a file with the notes of a melody. The microcontroller is configured to process a file with the notes of a melody to replay the notes of the melody in the start/stop mode and send 3 commands to the synthesiser in accordance with the processed file in place of commands for playing notes received from a MIDI keyboard.EFFECT: technical result is creation of an apparatus providing a possibility to insert the correct notes of a melody while playing a keyboard instrument.3 cl, 7 dwg

Description

The invention relates to the field of electronic musical instruments, in particular to devices for learning to play a musical instrument, and is a hardware-software device.

The following abbreviations are used in the description.

MIDI (Musical Instrument Digital Interface) is a digital sound recording standard for the format of data exchange between electronic musical instruments.

Ultra-Wide Band (UWB) is a short-range, low-power wireless technology that uses ultra-wideband signals with extremely low power spectral density as a carrier.

Bluetooth (from the English words blue - blue and tooth - tooth) is a production specification for wireless personal networks.

Wi-Fi (English Wireless Fidelity) is a wireless LAN technology.

In 1982, the MIDI standard was announced. All modern digital musical instruments are based on this standard. Schematically, any digital musical instrument consists of two parts. The first is the MIDI keyboard itself, on which the musician plays the melody. The keyboard can look like a piano or button accordion, have a different number of keys or octaves. The second is the so-called synthesizer, a device for playing a melody that a musician plays on a MIDI keyboard.

The MIDI keyboard and the synthesizer are connected by a two-wire cable, through which the musician's actions on the MIDI keyboard are transmitted to the synthesizer, i.e. which keys (notes) are pressed, at what speed, which keys (notes) are released - these are the main commands.

Since its inception, the MIDI standard has been continuously refined, expanded, improved, but for a performer practically nothing has changed. For example, playing a digital piano requires the same skills as a classical mechanical piano, and in this sense, the MIDI standard did not offer the performer anything new, except for various sound effects on a synthesizer.

Not so long ago, "auto accompaniment" began to be used in synthesizers, when the melodies performed by the musician can be accompanied by other virtual instruments up to the orchestra, but in this case the performer must be able to play and correctly hit the notes.

The closest analogue of the claimed invention is a device known from US Pat. No. 7,718,885, which is a musical synthesizer whose control signal flow is generated "live". A musician plays a keyboard that generates a control stream such as a MIDI stream. The small delay between receiving the MIDI stream and synthesizing the sound is used to start the next note transition before the note switch.

However, this solution does not allow substituting the correct melody notes while the musician is playing.

The technical problem to be solved by the invention is the creation of a device that allows you to substitute the correct notes of a melody while playing a keyboard instrument.

The technical result is a solution to the stated technical problem.

The claimed technical result is achieved due to the fact that the intelligent physical MIDI interface is adapted to be connected to a MIDI keyboard and synthesizer and contains a microcontroller, nonvolatile memory, a control device, a signal generator for MIDI input and a signal generator for MIDI output, while the nonvolatile memory is made with the ability to save a file with notes of a melody, the microcontroller is configured to process a file with notes of a melody for start-stop playback of notes of a melody and send commands to the synthesizer in accordance with the processed file instead of commands for playing notes received from a MIDI keyboard.

The claimed device can be used with any digital musical instruments using the MIDI interface, for example, digital pianos, digital button accordions, accordions, or simply the MIDI keyboard itself of any design. At the same time, the musical instruments themselves do not require any modification. The claimed device enables any person who has no musical training to play these instruments, i.e. he does not need to "hit the notes", tk. the correct notes sound when any keys are pressed. It is very important that the performer can control the tempo of the performance from very slow (up to a stop) to very fast, as well as the volume - from "very loud" (fortissimo) to "very quiet" (pianissimo). The combination of these factors gives a full sense of creative play and self-expression both for the performer himself and for his listeners, since different performers will have different styles of performance and individuality. Moreover, one and the same performer can interpret the same piece in different ways, without the need for musical literacy. The main thing is that a person seems to "step over" through long and tedious exercises-scales to train the technique, when already at the subconscious level the fingers "know" where the necessary keys-notes are.

The claimed device can be used for entertainment purposes, for home playing, music therapy, accompaniment for amateur singing, as an intellectual musical toy for children that develops musical taste.

The invention is illustrated using FIG. 1-7, which show:

FIG. 1 - connection of an intelligent physical MIDI interface;

FIG. 2 - device of intelligent physical interface MIDI;

FIG. 3 - algorithm of the intelligent physical interface MIDI;

FIG. 4 - the structure of the processed file;

FIG. 5 - structure of block A;

FIG. 6 - block B structure;

FIG. 7 - structure of block B;

FIG. 1-7, positions 1-13 indicate:

1 - intelligent physical MIDI interface;

2 - MIDI keyboard;

3 - synthesizer;

4 - two-wire cable;

5 - microcontroller;

6 - nonvolatile memory;

7 - control device;

8 - signal generator for MIDI input;

9 - signal generator for MIDI output;

10 - MIDI input connector;

11 - MIDI output connector;

12 - power supply connector;

13 - case.

The intelligent physical interface MIDI 1 consists of a microcontroller 5, non-volatile memory 6 and a control device 7, a signal conditioner for MIDI input 8 and a signal conditioner for MIDI output 9, structurally located in the same housing 13. The case has a MIDI input connector 10, a MIDI output connector 11, power supply connector 12.

Signal conditioners for MIDI input and output 8 and 9 conform to the MIDI standard and are designed to match the electrical levels of microcontroller 5 and the physical MIDI interface. They work after turning on the power of the microcontroller 5.

The microcontroller 5 is made in the form of a chip of the STM32F407 type or the like and contains a microprocessor, program and data memory, peripheral devices. In this case, two peripherals are used - an asynchronous serial interface: one for receiving, the other for transmitting MIDI data at a rate of 31,250 bits per second.

Nonvolatile memory 6 is designed to store notes of melodies in the form of standard MIDI files and interacts with the microcontroller 5 via a serial interface.

The control unit 7 allows you to set the operating modes of the device, select melodies and perform other service functions from any smartphone or other personal electronic device. The control device 7 can be made wireless using Bluetooth, UWB, Wi-Fi, etc. The control device 7 can be made wired, for example, in the form of a control panel.

The MIDI 10 input connector is intended for connection with a two-wire cable 4 of a MIDI keyboard 2, and the MIDI 11 output connector is for synthesizer 3.

The program memory of the microcontroller 5 stores a program that performs the entire algorithm of the intelligent physical interface MIDI 1.

The device is used as follows.

The intelligent physical MIDI interface 1 is inserted between the MIDI keyboard 2 and the synthesizer 3 in the break of the physical MIDI interface, as shown in FIG. 1.

The intelligent physical interface MIDI 1 has two main modes of operation: transparent and intelligent.

In transparent mode, the device passes all data unchanged from MIDI keyboard 2 to synthesizer 3, i.e. a simple physical MIDI interface is implemented and the intelligent physical MIDI interface 1 is not involved, i.e. the musician plays as usual.

In the intelligent mode, the notes of the melody that the performer is going to play on the MIDI keyboard 2 are loaded into the nonvolatile memory 6. When the performer presses a key from the MIDI keyboard 2 to the synthesizer 3, the “Turn on note” command is transmitted, and when released, the “Turn off note” command is sent.

Each command consists of three bytes:

- 1st byte - command code (enable or disable);

- 2nd byte - note number from 1 to 127 (numbering according to the MIDI standard);

- 3rd byte - keystroke velocity for the "Turn on note" command, not used for the "Turn off note" command.

This data is processed by microcontroller 5.

When the performer presses some keys (no matter what) on the MIDI keyboard 2, the data is sent for processing to the microcontroller 5 of the intelligent physical interface MIDI 1, and then, already changed according to the notes of the melody of the loaded file, this data is sent to the synthesizer 3.

Thus, the performer only initiates the transmission of the correct notes to synthesizer 3, but does not have to hit them.

The velocity of pressing the keys corresponding to the volume is set by the performer. Each time the player presses a key, the intelligent physical interface MIDI 1 transmits the next notes of the melody, prepares the next notes, and enters the standby mode for the player's keystrokes. Therefore, the overall tempo of the melody is also set by the performer with the frequency of keystrokes. However, the ratio of note durations to each other in a melody supports the intelligent physical interface MIDI 1 according to the current melody score. These operations are performed by a software-implemented algorithm in the microcontroller 5.

A block diagram of the operation algorithm of the intelligent physical interface MIDI 1 is shown in figure 3.

A rhombus with the letter "C" denotes events or conditions that imply the choice of an action, a rectangle with the letter "D" - the actions themselves.

Event C1

After turning on the power via the power supply connector 12, the intelligent physical MIDI interface 1 waits for a command from the control unit 7 - the number of the loaded MIDI file (melody).

Action D1

Further, the microcontroller 5 reads the corresponding MIDI file from the non-volatile memory 6 and converts it into a form convenient for the start-stop execution of the melody, receiving the processed file. This is a key point for the entire algorithm of the intelligent physical interface MIDI 1. A standard MIDI file is intended for continuous melody performance, the "On note" and "Off note" commands are linked to the internal software sync generator and do not explicitly contain note durations.

The structure of the processed file being executed is shown in Figure 4.

The processed file is an alternation of three types of blocks: A, B, C. Block A is of variable length and can include from one to several records. Each entry is a command of the "Turn on note" type, i.e. what notes of the melody should be sent to the synthesizer 3 at the current time (Fig. 5). Block B always includes only one record - this is the duration in milliseconds of the shortest note (or group of notes) from the previous block A (Fig. 6). Block B is of variable length and can contain from one to several records. Each record is a command of the "Turn off note" type, i.e. the sound of which notes of the melody should be stopped by the synthesizer 3 at the current time (Fig. 7). Each block has its own label for recognition.

Action D2

The next block of type A is read, but commands of the "Turn on note" type have not yet been transmitted to the synthesizer 3.

Event C2

This event consists in the performer pressing one or more keys on the MIDI keyboard 2, after which action D3 is performed.

Action D3

The frequency of keystrokes on a MIDI keyboard by 2 performer per 1 second is counted.

In all "Turn on note" commands (block A from D2), the key velocity (volume - 3rd byte) is replaced by the current key velocity of the performer on the MIDI keyboard 2.

All "Note On" commands (block A from D2) are sent to synthesizer 3, and the corresponding notes begin to sound.

Then block B is read (the shortest duration of a note or group of notes from block A). This duration changes in inverse proportion to the frequency of keystrokes by the performer on the MIDI keyboard 2 and is recorded in the program timer of the microcontroller 5 of the intelligent physical interface MIDI 1.

Event C3

In this event, every millisecond "1" is subtracted from the value in the program timer; if equal to zero, the transition to action D4 is carried out.

Action D4

The next block of type B is read by the "Turn off note" commands, these commands are immediately transmitted to the synthesizer, and the corresponding notes stop sounding.

Event C4

If the processed file being executed has ended, the transition to the analysis of the C1 event is carried out - waiting for a new command from the control device 7, otherwise - to the action D2, i.e. the melody continues.

Thus, from the considered algorithm, it is clear that no matter what keys the performer presses, the correct notes come to the synthesizer 3. But at the same time, the performer can change the tempo of the melody, stop and continue from the same place, change the volume of the performance, i.e. has the ability to express itself artistically through these dynamic shades.

Claims (3)

1. Intelligent physical MIDI interface, characterized in that it is configured to be connected to a MIDI keyboard and synthesizer and contains a microcontroller, nonvolatile memory, a control device, a signal generator for MIDI input and a signal generator for MIDI output, while the nonvolatile memory is configured saving a file with melody notes, the microcontroller is configured to process a file with melody notes for start-stop playback of melody notes and send commands to the synthesizer in accordance with the processed file instead of commands for playing notes received from a MIDI keyboard. 2. Intelligent physical MIDI interface according to claim 1, characterized in that the control device is wireless. 3. Intelligent physical MIDI interface according to claim 1, characterized in that the microcontroller is configured to send notes to the synthesizer, the ratio of the durations of which among themselves corresponds to the notes of the melody of the processed file.

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