JP2001356762A - Music data transmitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a music data transmitting device which transmits music data having the same contents and enables a reception side to reproduce the same musical performance irrelevantly to the kind of its interface in use when reproducing the musical performance. SOLUTION: A control part 10 of a MIDI-adaptive device 100 controls the timing of MIDI data supply to a communication part 50 so that the bit rate of the transmission of MIDI data through a high-speed interface is as high as the bit rate of the transmission of the MIDI data through a MIDI interface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a music data transmitting apparatus.

[0002]

2. Description of the Related Art In an electronic musical instrument such as an electronic piano, in addition to generating a musical tone using a sound source built in the electronic musical instrument,
Devices provided with a communication function of performing data communication with external devices have become widespread. For example, an electronic piano equipped with a communication function and an external sound source (sound source module, other electronic musical instruments, etc.)
Is connected, data generated by playing the keyboard of the electronic piano is transmitted to an external sound source, so that a musical tone can be generated using the external sound source. As described above, MIDI (Musical Instrument Digit) is used as a standard for performing data communication between an electronic musical instrument and an external sound source.
tal Interface) standard, and a device corresponding to the MIDI standard (hereinafter referred to as a MIDI device) is a MIDI device.
Interface is installed. By the way, in recent years, in the field of electronic musical instruments, with the remarkable progress of computer music, composition and arrangement are performed on a personal computer, and MIDI data (MIDI
After the MIDI data is generated, the MIDI data is transmitted to the electronic musical instrument, or the M of the electronic musical instrument is transmitted.
For example, IDI data is transmitted to a personal computer and edited on the personal computer. A personal computer for performing data communication with the electronic musical instrument is equipped with a MIDI interface compatible with the MIDI standard, and the personal computer performs data communication with the electronic musical instrument via the MIDI interface with the MIDI data. Was. However, MIDI defined in this MIDI standard
Interface communication speed (bit rate during communication)
As shown in FIG. 7, the communication speed is much lower than the communication speed of a serial interface such as IEEE 1394 or USB which is widely used in personal computers and the like at present. Therefore, performing data communication with the electronic musical instrument via the MIDI interface is not compatible with the IEEE1 standard that can perform high-speed communication.
394, which is extremely inefficient for a personal computer or the like having a serial interface such as a USB. In view of such circumstances, I can communicate at high speed.
Electronic musical instruments, tone generator modules, and the like (hereinafter, collectively referred to as MIDI-compatible devices) having serial interfaces such as EEE1394 and USB and capable of data communication with a personal computer or the like via these interfaces have been developed. . As a result, to date, instead of a MIDI device having only a MIDI interface, a MIDI-compatible device having an interface capable of high-speed communication in addition to the MIDI interface has been widely used.

[0003]

By the way, this MID
When transmitting MIDI data to an I-compatible device, the user first selects whether to transmit MIDI data using a MIDI interface or to transmit MIDI data using an interface such as IEEE1394. The device on the MIDI data transmission side and the MIDI-compatible device are connected using a cable conforming to the standard. This MIDI interface and IEEE
All interfaces such as E1394 are serial interfaces. For this reason, the MIDI-compatible device receives serial data from the transmission-side device regardless of which interface is used. Therefore,
For example, when a sound generating event such as a chord is generated in the transmitting device, the sound generating event of each sound constituting the chord is sequentially transmitted from the transmitting device via the serial interface. Here, the event (music event) refers to music information related to a performance, operation, and the like constituted by MIDI data (music data). FIG. 8 is a diagram for explaining a case where a chord sounding event is transmitted from a transmitting-side device to a MIDI-compatible device. More specifically, FIG. 8A shows the sounding timing of a sounding event received by the MIDI-compatible device via the MIDI interface, and FIG.
Indicates the sounding timing of the sounding event received via the high-speed interface. In the following description, an interface capable of performing data communication at twice the communication speed of the MIDI standard is referred to as a high-speed interface. When a sounding event relating to the chords of “do” and “so” is transmitted from the transmitting device to the MIDI-compatible device, the MIDI-compatible device first sets the sound of “do” (note number) to the intensity “10”.
Receiving sounding event 1 to be sounded (note on) at (velocity), and then sounding event 2 to be sounded (note on) at "20" (velocity) to the sound of "so" (note number) Receive (see FIG. 8). Upon receiving the event via the MIDI interface, the MIDI-compatible device starts sounding processing of sounding event 1 960 μs after the start of reception (starting of sounding event 1 shown in FIG. 8A), and further sounds after 960 μs. The sound generation process of event 2 is started. On the other hand, when a sounding event is received via the high-speed interface, the MIDI-compatible device starts sounding processing of the sounding event 1 480 μs after the start of reception (start of the sounding event 1 shown in FIG. 8B), and further 480 μs After the passage, the sound generation process of the sound generation event 2 is started. In this way, the sounding event to sound the sound of "do" and the sounding event to sound the sound of "so" that are simultaneously generated in the transmitting device are sent out in order, so any interface is used. Even in such a case, there is a gap between the timing at which the sound of "do" is emitted and the timing at which the sound of "so" is emitted. Various attempts have been made in the past to solve such a shift in sounding timing. For example, in order to obtain a synthesized waveform closest to the synthesized waveform that would have been obtained if the sounds were generated simultaneously, a waveform change process was performed on the waveform obtained when each sound was generated independently, and the change process was performed. For example, an optimum synthesized waveform is obtained using the obtained waveform. However, all such attempts have been made at the communication speed of the MIDI standard.
This is based on the premise that data will be exchanged.
Therefore, as shown in FIG. 8A, when MIDI data is received via the MIDI interface and tone generation processing is performed according to the MIDI standard, an optimum synthesized waveform is obtained. As shown in (1), when MIDI data is received via the high-speed interface at a communication speed higher than the MIDI standard, sound generation processing is performed at a timing earlier than the MIDI standard, and an optimum synthesized waveform cannot be obtained. As a result, in the conventional MIDI-compatible device, the same performance is not reproduced between the case where the data is received via the MIDI interface and the case where the data is received via the interface such as IEEE1394, even though the received data has the same contents. There was a problem.
The present invention has been made in view of the circumstances described above, and in the case of transmitting music data of the same content and reproducing the performance on the receiving side, the same performance is reproduced regardless of the type of interface used. It is an object of the present invention to provide a music data transmitting device capable of performing the following.

[0004]

According to a first aspect of the present invention, there is provided a music data transmitting apparatus including a low-speed interface and a high-speed interface. A transmitting unit that performs transmission, and the transmitting unit such that a bit rate when transmitting the music data via the high-speed interface is equal to a bit rate when transmitting the music data via the low-speed interface. And a transmission control unit for controlling.

According to a second aspect of the present invention, in the music data transmitting apparatus according to the first aspect, the transmission control unit is configured to control the high-speed interface according to a type of a music event constituted by the music data. Selecting whether or not to control the transmission unit such that a bit rate when transmitting the music data via the low-speed interface is equal to a bit rate when transmitting the music data via the low-speed interface. And

[0006]

Embodiments of the present invention will be described below to make the present invention easier to understand. Such an embodiment shows one aspect of the present invention, and does not limit the present invention, and can be arbitrarily changed within the scope of the present invention.

A. 1. First Embodiment (1) Configuration of Embodiment FIG. 1 shows a MIDI-compatible device 1 on the transmitting side according to the present embodiment.
FIG. 2 is a block diagram showing a configuration of a 00. The MIDI-compatible device 100 is provided with a MIDI interface and a high-speed interface, and is a device capable of transmitting and receiving data at a transmission rate twice that of the MIDI standard and the MIDI standard. Please refer to the contents). MIDI compatible device 10
0, a ROM 20, a RAM 30, a sound source 40, and a communication unit 5 via a bus 11.
0, a high-speed interface 51, a MIDI interface 52, and the like. Of course, this MIDI-compatible device 100 is equipped with a sound system and the like constituted by an amplifier, a speaker, and the like, like the existing MIDI-compatible device, but the description is omitted because it is not related to the gist of the present invention. .

The control unit 10 controls the MIDI-compatible device 100 based on the processing program stored in the ROM 20, while controlling the MIDI-compatible device 100 via the high-speed interface 51.
When transmitting DI data, a transmission interrupt program stored in a predetermined storage area of the ROM 20 is started, and
Controls transmission of MIDI data. The RAM 30 is a rewritable memory, and includes a transmission data storage area for storing MIDI data converted by the sound source unit 40, a reception data storage area for storing received MIDI data, and the like.
This is a FIFO memory having a plurality of storage areas.

The tone generator 40 generates musical sound data, converts the generated musical sound data into MIDI data of a format conforming to the MIDI standard, and outputs the converted MIDI data to the communication unit 50. The communication unit 50 has a role of transmitting and receiving MIDI data via the high-speed interface 51 and the MIDI interface 52. More specifically, the communication unit 50 adds a start bit (1 bit) and a stop bit (1 bit) to 1-byte MIDI data transferred from the transmission data storage area of the RAM 30, and adds the start bit and the stop bit. MIDI with
MIDI (10 bits) transmitted via each interface while MIDI received via each interface
The data is output to a sound system (not shown) including an amplifier, a speaker, and the like.

The high-speed interface 51 has a terminal called a "port" for connecting to a high-speed interface standard cable (hereinafter, referred to as a high-speed cable). By connecting the cable to this terminal, bi-directional serial communication becomes possible. The MIDI interface 52
It has an input terminal and an output terminal for connecting to a MIDI standard cable. By connecting the cable to this input terminal or output terminal, unidirectional serial communication becomes possible. Next, in the MIDI-compatible device 100 having such a configuration, M
A specific operation when transmitting IDI data will be described. The specific operation of the MIDI-compatible device 100 described below is based on the assumption that MIDI data generated in real time in the sound source unit 40 is transmitted to the external device 200, but the present invention is not limited to this. For example, the present invention is also applicable to a case where MIDI data (for example, edited music or the like) stored in the RAM 30 or the like in advance is transmitted to the external device 200.

(2) Operation of Embodiment First, a user uses a high-speed cable to connect to the MIDI-compatible device 100 and an external device 200 to which MIDI data is to be transmitted.
(See FIG. 2). The external device 200
Is a MIDI-compatible device provided with a high-speed interface and a MIDI interface similarly to the MIDI-compatible device 100. However, in order to facilitate understanding of the description, MIDI is used.
The device on the data transmission side is called a MIDI-compatible device 100,
The device on the MIDI data receiving side is called an external device 200.

When a high-speed cable is inserted into the terminal of the high-speed interface 51, the communication unit 50 of the MIDI-compatible device 100 notifies the control unit 10 that the transmission and reception of MIDI data via the high-speed interface 51 is enabled. . In response to this, the control unit 10 that controls the entire MIDI-compatible device 100 activates a transmission processing program stored in the ROM 20 to start transmission control of MIDI data.

FIG. 3 is a flowchart showing a control flow of the transmission process. First, the control unit 10 refers to the transmission data storage area of the RAM 30 and determines whether there is MIDI data to be transmitted (step S1). Here, it is assumed that the MIDI data to be transmitted has not been generated in the sound source unit 40 yet. Since the MIDI data has not yet been stored in the transmission data storage area of the RAM 30, the control unit 10 determines that there is no MIDI data to be transmitted (step S1; NO), and
Until the DI data is stored in the transmission data storage area of the RAM 30, the process of step S1 is repeatedly executed.

Thereafter, it is assumed that the user starts playing the keyboard. As a result, the sound source unit 40 receives the MI based on the keyboard performance.
Start generation of DI data. The MIDI data generated by the sound source unit 40 is sequentially stored in a transmission data storage area of the RAM 30. When the MIDI data is stored in the transmission data storage area of the RAM 30, the control unit 10
Determines in step S1 that there is MIDI data to be transmitted, and proceeds to step S2. Step S2
In, the control unit 10 determines whether or not a clock timer (not shown) is running. The clock timer is started by the control unit 10 executing the process of step S3. And the timer starts 320μs
When the time measurement is completed, the control unit 10 is notified. Therefore, in step S2, the control unit 10 has not started the clock timer yet, so the determination result is “NO”, and the control unit 10 proceeds to step S3.

In step S3, the control unit 10
The MIDI data to be transmitted from the transmission data storage area of the AM 30 to the communication unit 50 is transferred, and a clock timer is started. It should be noted that the MI 30
The transfer of DI data is performed in 1-byte units. When the MIDI data is transferred from the RAM 30 to the communication unit 50 in this manner, the control unit 10 returns to step S1 and refers to the transmission data storage area of the RAM 30 to determine whether there is MIDI data to be transmitted. I do. When the control unit 10 determines that there is MIDI data to be transmitted, the control unit 10 determines whether or not a clock timer has been activated (step S1 → step S2). As described above, when 320 μs elapses, the clock timer notifies the control unit 10 of that fact. Therefore, the control unit 10 determines that the time
This step S
Step 2 is repeatedly executed. Thereafter, while the control unit 10 repeatedly executes the process of step S2, 320
It is assumed that μs has elapsed. At this time, the clock timer is controlled by the control unit 10.
To that effect, and ends the timing operation. When receiving this notification, the control unit 10 shifts the processing from step S2 to step S3. And the control unit 10
Transfers the MIDI data from the transmission data storage area of the RAM 30 to the communication unit 50 in step S3, and starts the clock timer again. And the control unit 1
0 returns to step S1 again, and repeats the flow control according to the above procedure.

When the control unit 10 executes such transmission processing, the MIDI data to be transmitted is 320 μs.
Are transferred from the RAM 30 to the communication unit 50 one byte at a time at intervals of. On the other hand, the control unit of the conventional MIDI-compatible device determines the transmission control flow shown in FIG. 4, that is, whether or not there is MIDI data to be transmitted to the RAM 30 (step Sa1). , From the RAM 30 to the communication unit 50
The I data has been transferred (step Sa2). Returning to the description of the present embodiment, when the k communication unit 50 receives the MIDI data, the k communication unit 50 adds a start bit (1 bit) and a stop bit (1 bit) to the received MIDI data (1 byte). The MIDI data (10 bits) to which the bit and the stop bit are added are sequentially transmitted to the external device 200 via the high-speed interface 51.

FIG. 5A shows that the external device 200 is a MIDI device.
FIG. 5B is a diagram schematically illustrating MIDI data received via the interface 52. FIG.
0 is MIDI received via the high-speed interface 51
It is the figure which showed the data typically. The external device 200
When using the MIDI interface 52, FIG.
As shown in FIG.
MIDI data having a 0-bit configuration is received, the sound generation process of the sound generation event 1 is started 960 μs after the start of reception, and the sound generation process of the sound generation event 2 is started after 960 μs has elapsed. On the other hand, in the present embodiment, similarly, when the high-speed interface 51 is used, the sounding process of the sounding event 1 is started 960 μs after the start of reception, and the sounding process of the sounding event 2 is further started after 960 μs. (FIG. 5 (b)). For this reason, the composite waveform obtained by the external device 200 performing the simultaneous tone generation process is always the optimal waveform.

B. Second Embodiment In the above-described first embodiment, the transmission speed of the MIDI compatible device 100 is controlled in order to obtain compatible reproducibility of performance. In the second embodiment described below, M
There is no change in controlling the transmission speed of the IDI-compatible device 100, but the data to be transmitted is controlled in a different manner from the first embodiment. The second shown below
The MIDI-compatible device 100 according to the embodiment controls the transmission speed only for data requiring real-time among the MIDI data to be transmitted, and transmits the data not requiring real-time according to the interface standard used. Configuration.

Therefore, first, M which needs real-time properties
Each of the IDI data and the MIDI data that does not require real-time properties will be described. MIDI data can be roughly classified into two types. These are channel messages and system messages. The channel message is a message relating to general performance information such as the above-mentioned note-on / note-off, program change, etc., and is a message for controlling a sound source in real time.
System messages are system exclusive
Like a message, this is a message that controls the entire MIDI system. Device settings (initial settings)
Etc. are non-real-time messages set before using the device.

FIG. 6 is a flowchart showing a control flow of the transmission processing in the present embodiment. The control flow shown in FIG. 6 is the same as the control flow shown in FIG. 3 except that step Sb1 has also been performed. When transmitting MIDI data, the MIDI-compatible device 200 according to the present embodiment determines whether the MIDI data to be transmitted is a channel message or a system message (step Sb1). Here, the transmission target M
When it is determined that the IDI data is a channel message (step Sb1; YES), the transmission speed is controlled and the MIDI data is transmitted (step Sb1 → step S2 → step), as in the first embodiment. S3). On the other hand, when the MIDI data to be transmitted is a system message (step Sb1; NO),
The MIDI data is transmitted at the transmission speed of the interface standard to be used (step Sb1 → step S3). Whether the MIDI data to be transmitted is a channel message or a system message is determined by using data characteristics defined in the MIDI standard (for example, referring to the upper 4 bits of the MIDI data). However, the present invention is not limited to this, and other determination methods may be employed.

As is clear from the above description, the MIDI-compatible device 100 according to the present embodiment is capable of transmitting a system message that does not affect the sounding timing or the like when reproducing a performance at a high speed according to the high-speed communication interface standard. Channel messages that are transmitted to the
MIDI data is transmitted at a time interval of 20 μs, that is, at the same rate as the communication speed of the MIDI standard. Therefore, when receiving MIDI data of the same content, the same performance can always be reproduced regardless of the type of interface used, and the communication system can be effectively utilized. It should be noted that the second embodiment is also modified in the same manner as the first embodiment (in advance, RA
MIDI data stored in M30 or the like
00 etc.) can be added.

C. Others In the first and second embodiments described above, a high-speed interface capable of communicating at twice the communication speed of the MIDI standard has been exemplified as a representative of an interface capable of communicating at a communication speed higher than the MIDI standard. However, the present invention is applicable to a high-speed serial interface such as IEEE 1394 and USB. Further, the first embodiment and the second embodiment
In the embodiment, the transmission rate of MIDI data is controlled so that the external device 200 can always process events according to the MIDI standard regardless of the type of interface used. It is not intended to be limiting. For example, MIDI in the external device 200
By controlling the data read speed, the external device 200 is configured so that event processing can be performed according to the MIDI standard. Specifically, the MIDI compatible device 10
0 transmits MIDI data via the high-speed interface according to the high-speed interface standard. External device 200
Receives MIDI data from the MIDI-compatible device 100 via the high-speed interface,
The DI data is stored in the RAM 30. When processing an event, the control unit of the external device 200
Control the reading speed of MIDI data based on the standard,
Process events according to MIDI standards. in this way,
A configuration for controlling the MIDI data reading speed in the external device 200 may be employed. Further, in the present embodiment, the description has been given by taking the MIDI data conforming to the MIDI standard as an example, but the present invention is not limited to this, and can be applied to music data not conforming to the MIDI standard. Also,
In the first embodiment and the second embodiment, when transmitting MIDI data using the high-speed interface,
A waiting process (step S2 shown in FIGS. 3 and 6) is provided in the control flow executed by the control unit 10 in order to transmit MIDI data at the same rate as the communication speed of the MIDI standard.
The set time of 320 μs in the waiting process can be appropriately changed according to the bit length of the MIDI data to be transmitted.

[0023]

As described above, according to the present invention,
When music data of the same content is transmitted and a performance is reproduced on the receiving side, there is an effect that a music data transmission device capable of reproducing the same performance regardless of the type of interface used can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a MIDI-compatible device 100 according to a first embodiment of the present invention.

FIG. 2 is a MIDI-compatible device 100 according to the embodiment;
FIG. 4 is a diagram showing a connection state between the external device 200 and the external device 200.

FIG. 3 is a flowchart illustrating a transmission interruption process according to the first embodiment.

FIG. 4 is a flowchart showing a control flow of a conventional transmission interruption process.

FIG. 5 is a diagram for explaining timing of generating MIDI data in the embodiment.

FIG. 6 is a flowchart illustrating a control flow of a transmission interruption process according to the second embodiment.

FIG. 7 is a diagram illustrating a relationship between an interface and a communication speed.

FIG. 8A is a diagram for explaining the sounding timing of MIDI data received via the MIDI interface, and FIG. 8B is a diagram for explaining sounding timing of MIDI data received via the high-speed interface. FIG.

[Explanation of symbols]

100: MIDI-compatible device 50: Communication unit 51: High-speed interface 52: MID
I interface 10 ... Control unit

Claims (2)

[Claims] A transmission unit that includes a low-speed interface and a high-speed interface, and that transmits music data by one of the low-speed interface and the high-speed interface; and a bit rate when the music data is transmitted via the high-speed interface. And a transmission control unit for controlling the transmission unit so as to be equal to a bit rate when transmitting the music data via the low-speed interface. 2. The transmission control unit, according to a type of music event constituted by the music data, sets a bit rate for transmitting the music data via the high-speed interface via the low-speed interface. 2. The music data transmitting apparatus according to claim 1, wherein whether or not to control the transmitting unit is selected so as to be equal to a bit rate when transmitting the music data.