JP2010176147A - Bus system for electronic musical instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a communication among a plurality of kinds of devices constituting an electronic musical instrument through a bus. <P>SOLUTION: When a main controller device 10 communicates with a keyboard device 14, the communication is carried out by a standard protocol. In this case, the main controller device 10 serves as a master to constitute a header part of an address unique to the keyboard device 14 which is a slave address as a transmission destination address and an address for the standard protocol of the main controller device 10 as a transmission source address and sends it to an E bus 11 together with a data part. Since the transmission destination address matches the address of the keyboard device 14, the keyboard device receives the transmission source address and the data part following the transmission destination address. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a bus system for an electronic musical instrument that is suitable for being incorporated in an electronic musical instrument.

  In an electronic musical instrument having only one CPU (Central Processing Unit) in a conventional electronic musical instrument, a panel such as a keyboard switch for detecting operation of each key on the keyboard and a panel switch for performing various settings such as tone settings The operation element is connected to a parallel I / O (Input-output). Then, the CPU captures the operation information of the keyboard switch and the panel operator via the parallel I / O, generates a sound source parameter based on the captured operation information, and transfers the sound source parameter to the sound source in accordance with the sound generation timing. By trying to pronounce it.

  In addition, a conventional electronic musical instrument that includes a plurality of CPUs is also known. In such an electronic musical instrument having a plurality of CPUs, the functions are shared by the plurality of CPUs. For example, the keyboard CPU scans the keyboard switch to detect and output the operation information of each key, and the panel CPU scans the panel operator to detect the operation information of each panel operator. Output and display control of the panel display. Further, the main CPU receives a keyboard operation signal from the keyboard CPU and a panel controller operation information from the panel CPU, generates a sound source parameter based on the operation information, and uses the sound source parameter as a sound source corresponding to the sound generation timing. It is made to pronounce by transferring. In this case, the main CPU is independently connected to the keyboard CPU and the panel CPU via a serial communication path, and communicates with each other via the serial communication path.

  In an electronic musical instrument having only one conventional CPU, the function and shape differ from product to product, so a board built in the electronic musical instrument must be designed and installed each time. There is a problem that the board mounted on the product cannot be diverted.

  Further, in the conventional electronic musical instrument having a plurality of CPUs, the communication specifications between the main CPU and the keyboard CPU and the communication specifications between the main CPU and the panel CPU are determined for each product. In some cases, the various substrates mounted on the product or other products cannot be connected to each other, and the substrates cannot be used. Furthermore, for example, when a plurality of keyboards are required, a new keyboard board on which the keyboard CPU is mounted must be connected to the main board on which the main CPU is mounted. Then, there was a problem that new connection hardware had to be added to the main board, and the main board had to be re-developed.

  Accordingly, an object of the present invention is to provide an electronic musical instrument bus system capable of performing communication between a plurality of types of devices constituting an electronic musical instrument through the bus by connecting the device to the bus. Yes.

  In order to achieve the above object, the present invention has the main feature that an electronic musical instrument is configured by connecting a host device connected to a bidirectional serial bus, an operation input device, and a MIDI device. .

  According to such an invention, an electronic musical instrument can be configured by arbitrarily connecting a keyboard or panel operation input device or a MIDI device to a bus to which a host device is connected.

It is a block diagram which shows the hardware constitutions in the Example of the electronic musical instrument to which the bus system for electronic musical instruments of this invention is applied. It is a block diagram which shows the outline | summary of the connection of the bus system for electronic musical instruments concerning the Example of this invention. It is a figure which shows the specific structure of the E bus system concerning the Example of this invention. It is a figure which shows the waveform timing diagram at the time of the data transfer in the SCL line and SDA line in the E bus system concerning the Example of this invention. It is a table which shows category ID, subaddress range, category name, and applicable communication protocol in the E bus system concerning the Example of this invention. It is a figure which shows the data format in the E bus system concerning the Example of this invention. It is a table | surface which shows the command of host transmission of a common protocol in the E bus system concerning the Example of this invention, and host reception. It is a table | surface which shows the command of host transmission and host reception of the standard protocol in the E bus system concerning the Example of this invention. It is a table | surface which shows the command of host transmission / reception of the MIDI protocol in the E bus system concerning the Example of this invention. It is a flowchart which shows the E bus starting procedure in the E bus system concerning the Example of this invention. It is a flowchart of the host reception process in the E bus system concerning the Example of this invention. It is a flowchart of the host transmission process in the E bus system concerning the Example of this invention. It is a flowchart of the keyboard transmission / reception process in the E bus system concerning the Example of this invention. It is a flowchart of the MIDI transmission / reception process in the E bus system concerning the Example of this invention.

FIG. 1 is a block diagram showing a hardware configuration of an embodiment of an electronic musical instrument to which the bus system for an electronic musical instrument of the present invention is applied, and FIG. 2 shows an outline of connection of the bus system for the electronic musical instrument of the present invention.
The bus system for an electronic musical instrument of the present invention is shown as an E bus system comprising an E bus 11 built in the electronic musical instrument 1 shown in FIG. 1 and an E bus system comprising an E bus 11 shown in FIG. The E bus 11 in the E bus system includes a main controller device 10 (including a main board 10a on which a main CPU (Central Processing Unit), a main ROM (Read Only Memory), a main RAM (Random Access Memory), and the like are mounted. Host device), panel devices 12 and 13 having panel CPUs, panel ROMs, panel RAMs, and the like, respectively, and keyboard substrates having keyboard CPUs, keyboard ROMs, keyboard RAMs, and the like. Keyboard devices 14 and 15 having 14a and 15a, respectively, and a MIDI device 16 having a MIDI substrate 16a on which a MIDI CPU, MIDI ROM, MIDI RAM, and the like are mounted are connected.

  The main controller device 10 controls the overall operation of the electronic musical instrument 1 to generate musical sounds based on the operation information of the keyboard switches and the panel controls taken from the keyboard devices 14 and 15 and the panel devices 12 and 13. Control processing and control processing for generating musical sounds according to a MIDI (Musical Instrument Digital Interface) message received from the MIDI device 16 are performed. The main ROM mounted on the main board 10a in the main controller device 10 stores a control program executed by the main CPU and preset data such as timbre data, accompaniment patterns, and music data. Further, in the RAM mounted on the main board 10a, a working memory area used when the main CPU executes a control program and the like, a user area such as timbre data and an accompaniment pattern, and the like are set.

  Further, the panel devices 12 and 13 are provided with panel switches for tone setting and effect setting, panel controllers such as a volume controller and a wheel, a continuous controller such as a volume and a wheel, and a JOG controller. Has been able to change. The panel CPU scans the panel operators provided in the panel devices 12 and 13 and detects the operation events and the operation amounts. In this case, the operation amount is detected as a relative value depending on the panel operator. In the panel ROMs mounted on the panel substrates 12a and 13a in the panel devices 12 and 13, respectively, a scan program executed by the panel CPU is stored. Furthermore, areas such as a working memory area used when the panel CPU executes a scan program or the like are set in the panel RAMs respectively mounted on the panel substrates 12a and 13a.

  Furthermore, the keyboard devices 14 and 15 are provided with a plurality of keys and a keyboard switch that is turned on / off according to the operation of each key. The keyboard CPU scans keyboard switches provided in the keyboard devices 14 and 15 to detect note-on / note-off key events, velocity and aftertouch values. The keyboard ROMs respectively mounted on the keyboard substrates 14a and 15a in the keyboard devices 14 and 15 store scan programs executed by the keyboard CPU. Furthermore, a working memory area used when the keyboard CPU executes a scan program or the like is set in the keyboard RAM mounted on each of the keyboard boards 14a and 15a.

  The MIDI device 16 is a MIDI compatible device such as a MIDI input / output device having a MIDI terminal or a To Host terminal, a MIDI sequence device capable of automatic performance, a MIDI keyboard or the like, and is connected to a host computer. A Host terminal can be provided. In the E-bus system, the MIDI device 16 can transmit and receive performance data and performance-related data in the MIDI format. The MIDI CPU controls the operation of the MIDI device 16, and the MIDI ROM mounted on the MIDI board 16a in the MIDI device 16 stores a MIDI control program executed by the MIDI CPU and MIDI control data. Further, a working memory area used when the MIDI CPU executes a MIDI control program or the like is set in the MIDI RAM mounted on the MIDI board 16a. If the MIDI device 16 is provided with a To Host terminal, the electronic musical instrument 1 can be a model with a To Host terminal.

  In the electronic musical instrument 1 shown in FIGS. 1 and 2, the main controller device 10 includes an E bus 11 that connects the main controller device 10 and the panel devices 12 and 13, the keyboard devices 14 and 15, and the MIDI device 16. The performance-related data relating to performance event data, tone color, etc. is received via the bus 21. When the event start time is reached, the sound source control data is sent to the sound source units 22, 23, 24 via the bus 21 to start generating musical sounds. The musical sounds generated by the sound source units 22, 23, 24 are supplied to the sound system 32 via the bus 31 and are emitted from the sound system 32. Other units can be connected to the bus 21 via I / O units 25 and 26.

  By the way, when the main controller device 10, the panel devices 12, 13, the keyboard devices 14, 15 and the MIDI device 16 are connected to the E bus system according to the embodiment of the present invention, as shown in FIG. A connector provided at one end of a wire constituting the E bus 11 is attached to the bus terminal of the board. The other end of the wire is connected to a signal line and a power supply line constituting the E bus 11 in the branch substrate 17. In this way, by attaching the connector of the E bus 11 to the board of each device, the device can be connected to the E bus system. For this reason, it is possible to add / remove devices from / from the E bus system by detaching the devices from the connector of the E bus 11 as necessary. Note that power is supplied from the E bus 11 to devices connected to the E bus system. In the case of the configuration shown in FIG. 2, power is supplied to the branch substrate 17 from a power supply unit (not shown). The connector of the E bus 11 is, for example, 7 pins, of which 3 pins are used for signal lines and the remaining 4 pins are used for power supply.

  When the E-bus system according to the embodiment of the present invention is used in the electronic musical instrument 1, for example, when the electronic musical instrument 1 is to be an organ type two-stage keyboard electronic musical instrument model, as shown in FIG. The keyboard device 15 may be attached to a connected E-bus connector such as a main board or a panel board. If it is desired to use a three-stage keyboard electronic musical instrument model, a keyboard device may be further attached to the connector of the E bus 11. Furthermore, in an electronic musical instrument in which a main board, a panel board, and a keyboard board are connected to an E bus, for example, a 61-key electronic musical instrument model can be changed to a 76-key electronic musical instrument model by exchanging only the keyboard device. Furthermore, by replacing the panel device, it is possible to correspond to a model with many or few panel switches. As described above, it is possible to freely add, delete, or change some of the plurality of substrates constituting the electronic musical instrument.

The E bus system which is a bus system for an electronic musical instrument according to the present invention will be described in detail below.
The E bus system is a bi-directional serial bus, and signal lines include a serial clock line (hereinafter referred to as “SCL line”), a serial data line (hereinafter referred to as “SDA line”), and an initial clear line. It is a book. In this case, a data signal synchronized with the clock sent to the SCL line is sent to the SDA line. A reset signal is sent to the initial clear line when the E bus system is started up or reset. The E bus system has four power lines, and power is supplied from the power lines to devices connected to the E bus system. The communication speed of the E-bus system can be either 100 kbps, 400 kbps, or 3.4 Mbps.

  In addition, a plurality of devices can be sequentially connected (bus type connection) to the E bus system, and the connected devices have unique and unique addresses. This unique address is, for example, 7 bits. This unique address table is shown in FIG. 5. The unique address is composed of a 4-bit category ID and a 3-bit sub-address. The category ID indicates the category type of the device, and the sub-address is an address indicating the own device among the devices of the same category. The category ID, which is a higher-order address indicating the category type, is set in advance according to the category type of the device when the board of the device is created, and the subaddress is the subaddress of another device of the same type when incorporated in the electronic musical instrument 1. It is set by a jumper pin or a dip switch so that it does not overlap. The types of categories include a host system to which the main controller device 10 belongs, a keyboard system to which keyboard devices 14 and 15 belong, a panel system to which panel devices 12 and 13 belong, a MIDI system to which MIDI devices belong, and a keyboard / panel. Keyboard / panel composite system.

  Communication between devices on the E-bus system is communication by master / slave operation, and multi-master is possible. The master is a device that can start data transfer on the E-bus system, generate a clock pulse that enables transfer, send it to the SCL line, and end the data transfer. A slave is a destination device that is addressed by a master. Multi-master means that a plurality of masters can simultaneously control the E-bus system without losing messages.

  Further, in the E bus system, when a plurality of masters try to transfer data onto the E bus system at the same time, a data collision detection function and an arbitration function are provided to prevent data destruction. Yes. In the E-bus system, arbitration is performed according to the priority order of category names in the destination device. The category name is an extension of the category type, and FIG. 5 shows a table of unique addresses and category names. As for the priority, the priority of the general call where the category name is the destination of all devices is the highest, the category name is the host system priority, the category name is the keyboard priority. 3rd, category name is 4th in keyboard / panel priority, category is 5th in panel, and category is last in MIDI. . These priorities are determined in consideration of importance and real-time characteristics.

  Further, in the E bus system, communication is performed using a communication protocol corresponding to the category name to which the address belongs at the transmission source address and the transmission destination address. FIG. 5 shows a table of category names and communication protocols. As shown in FIG. 5, when communication is performed between the keyboard system to which the keyboard devices 14 and 15 or the panel system to which the panel devices 12 and 13 belong and the host system to which the main controller device 10 belongs, Communication is performed using a standard protocol, which will be described later. Further, when communication is performed between the MIDI system to which the MIDI device 16 belongs and the host system to which the main controller device 10 belongs, communication is performed using a MIDI protocol, which will be described later, which is a protocol for transmitting performance information. When the category name is general call, the host system communicates with the keyboard system, panel system, and MIDI system using a common protocol, which will be described later, which is a control protocol. The common protocol is composed of common parts of the standard protocol and the MIDI protocol. Note that only the host system can transmit to the general call address “0000 000”. If other keyboard, panel, and MIDI devices want to transmit using a common protocol, their own unique address. Is used.

  In this way, the host main controller device 10 can communicate with the communication protocol adapted to the category name. When the host system communicates with a device of another category name, it is necessary to determine a communication protocol. However, prior to communication, the host system addresses a destination address. This transmission destination address is a unique address in the device, and the upper 4 bits of the unique address are a category ID. Therefore, the host system can know the category name of the communication partner device and the communication protocol to be used from the transmission destination address with reference to the table of FIG. As shown in FIG. 5, the host is given two unique addresses corresponding to two communication protocols of the host system, and uses the address of the communication protocol adapted to the category name of the device that is the communication partner. To communicate. In addition, the host device can perform communication using a standard protocol, in which one of the two unique addresses and the general call address is used.

Next, a specific configuration of the E bus system according to the present invention is shown in FIG. However, FIG. 3 shows only two signal lines of the SCL line and the SDA line among the seven wires constituting the E bus system. A signal line (not shown) is an initial clear line (E-IC), and the remaining four wires are power lines.
As shown in FIG. 3, device 1 (Device 1), device 2 (Device 2), and device 3 (Device 3) are bus-connected to the SCL line and the SDA line, respectively. Since the connection configuration of each device and the SCL line and SDA line is the same, only the device 1 will be described. In the device 1, a buffer B2 serving as a clock input unit (SCL IN) is connected to an SCL line to which a clock is transferred, and a clock pulse is taken into the device 1 through the buffer B2. The SCL line is connected to the drain of a field effect transistor (hereinafter referred to as “transistor”) TR2 which is an open drain serving as a clock output unit (SCL OUT), and the clock pulse is turned on / off by turning on the transistor TR2. Can be sent to the SCL line. Further, a buffer B1 serving as a data input unit (SDA IN) is connected to the SDA line to which the data signal is transferred, and the data signal is taken into the device 1 through the buffer B1. The SDA line is connected to the drain of the transistor TR1, which is an open drain serving as a data output section (SDA OUT), and a data signal can be sent to the SDA line by turning on / off the transistor TR1.

  The devices 2 and 3 are also connected to the SCL line and the SDA line with the same circuit configuration. In the devices 1 to 3 shown in FIG. 3, the transistors TR1 to TR6 are field-effect transistors, but may be bipolar transistors that are open collectors. Further, the SCL line and the SDA line are each pulled up by a pull-up resistor Rp. That is, the SCL line and the SDA line are at a high (H) level in the open state, and when the transistors TR1, TR3, TR5,. L) Level. That is, the data output units of the devices 1 to 3 are wired and connected to the SDA line. Similarly, the SCL line becomes H level in the open state, and the SCL line becomes L level when any of the transistors TR2, TR4, TR6,. That is, the clock output units of the devices 1 to 3 are wired and connected to the SCL line.

  FIG. 4 shows a waveform timing chart at the time of data transfer on the SCL line and the SDA line in such an E bus system. In the E bus system, data transfer can be started only when the bus is in an open state (H level), and at the start of data transfer, the master transfers a start bit. In this case, when the SCL line is at the H level (open state), the start bit is sent as shown by inverting the SDA line to the L level. When the device connected to the E bus system detects this start bit, the device knows that data transfer is started. Next, the header portion placed in front of the data portion is transferred. The data part is composed of a plurality of bytes (1 byte = 8 bits), and the header part is also composed of a plurality of bytes. In this header portion, the first 1 byte is composed of a 7-bit transmission destination address (slave address) and 1 bit for instructing data reading / writing (R / W), and a 7-bit transmission source address ( The next one byte is composed of a master address) and one dummy bit of “0”. Subsequent to the header portion, a data portion in which data of 1 byte unit is continuous for 3 bytes or 15 bytes as described later is transferred. A clock pulse is sent to the SCL line in synchronization with each bit of the header part and the data part. In this case, since the header part and the data part are composed of data in units of 1 byte, the clock pulse synchronized with each bit is 1, 2, 3 for each byte of the header part and the data part as shown in the figure. ... 8 of 8 are sent out. The timing at which the level of each bit in the header portion and the data portion can be inverted is a period in which the clock pulse is at the L level, and in a period in which the clock pulse is at the H level so that the data of each bit is valid. , The level of the SDA line must be stabilized and transferred.

In the E bus system, a clock pulse, a header portion, and a data portion transmitted from the master reach all devices via the SCL line and the SDA line. Therefore, each device compares the slave address in the header part received first and the address unique to the device one bit at a time. If the 7-bit slave address matches the address of its own device, it knows that its own device has been addressed as a slave and receives subsequent data. In addition, when the SDA line level is L (or H) and the corresponding address bit of the own device is “1” (or “0”), the address of the own device is addressed as a slave address. It is determined that the device itself is not the data transfer destination, and the subsequent received data is discarded. This allows only the addressed device to receive data.
In the header part, the 8th bit in each byte is a bit for instructing data reading / writing. In the E bus system, this bit is always set to L (= “0”). The data format has only writing. An electronic musical instrument requires a real-time response to an operation of a keyboard, a panel, etc. As described above, the response is enhanced by transmitting an operation event in the keyboard system and the panel system to the host system by writing.

By the way, the master sends out the next 1-byte signal after knowing that the 1-byte signal in the header part or data part sent to the SDA line has been normally received. Therefore, after the 1-byte signal is transmitted, the master transmits the 9th clock pulse (ACK) for acknowledgement indicating whether or not the 1-byte signal is received as a valid signal to the SCL line. . At the same time, the master opens the SDA line to the H level. When the 1-byte signal is received as a valid signal, the destination device addressed by the slave address in the header section turns on the transistor in the data output section and holds the SDA line at the L level. To do. The master captures the level of the SDA line during the period when the ninth ACK clock is at the H level, and if the acknowledge is at the L level, the master knows that the transmission destination device has normally received the 1-byte signal. As a result, the master can send the next 1 byte to the SDA line. At this time, the transmission destination device holds the SCL line at the L level until it is ready for reception. After a predetermined time, the master sequentially starts sending the next 1 byte to the SDA line from the first bit, and starts sending synchronized clock pulses to the SCL line. Here, when the transmission destination device is ready for reception, the clock pulse of the SCL line sequentially rises, and the transmission destination device can capture the next 1-byte data in accordance with the clock pulse. On the other hand, when the destination device is not ready at that time, the SCL line is held at the L level by the destination device. Therefore, the clock pulse that the master tried to send does not appear on the SCL line, and the master waits for the SCL line to rise. When the transmission preparation of the transmission destination device is completed, the SCL line is released, so that the clock pulse rises on the SCL line and the next 1 byte is transmitted.
If the transmission destination device cannot receive a valid 1-byte signal, an H level acknowledge is generated and the master receives the acknowledge. In this case, the master sends a stop bit by inverting the SDA line to the H level while holding the SCL line at the H level, and stops the data transfer. The stop bit is transmitted on the E bus 11 by the master even when the communication is terminated.

  Next, arbitration will be described. In the E bus system, data transfer can be started only when the bus is in an open state (H level), but a plurality of devices may start data transfer almost simultaneously as a master. In this case, arbitration for permitting communication to one of the masters is performed. This arbitration utilizes the fact that the data output transistor of each device is wired and connected to the SDA line. More specifically, when data transfer is started, the slave address is sent to the SDA line following the start bit as shown in FIG. Contrasts the slave address addressed bit by bit. In this case, when data is sent from a plurality of devices to the SDA line at the same time, since any device sends L level, the SDA line is held at L level because it is wired-and. Become.

  Then, depending on the device, the bit compared with the slave address designated by the own device is “1”, whereas the bit fetched from the SDA line is “0” (= L level). If the addresses do not match as described above, it is determined that the priority order of the other masters is high, and the data output unit is turned off. If this process is continued, communication is finally permitted to the master with the highest priority. As described above, the priority order in this case is such that the SDA line level is given priority to the L level, and therefore, the priority order of the address that continues with “0” from the most significant bit (MSB) as the slave address is high. It will be. The priority in the arbitration is determined by the category name. As described above, the general call is the highest, and the second is the host system (main controller) device as the destination. The ranking is when the keyboard device is the transmission destination, the fourth ranking is when the panel device is the transmission destination, and the fifth ranking is when the MIDI device is the transmission destination. The reason why the order of the keyboard system is high is that real-time performance is important for the keyboard.

  For this reason, a category ID is assigned to each category according to the priority order of the category names as shown in FIG. FIG. 5 is a table showing category IDs, subaddress ranges, category names, and types of communication protocols used. Referring to the category ID in the table shown in FIG. 5, the category ID of the general call transferred to all devices is “0000”, and “0” lasts the longest. The category ID of the host system (main controller) is “0001”, the category ID of the keyboard system is “0010”, the category ID of the panel system is “0011”, and the category ID of the keyboard / panel composite system Is “0100” and the MIDI category ID is “0101”. As a result, arbitration can be performed in the above-described priority order. When the category IDs are the same and the master is not determined only by comparing the category IDs, the master is determined by comparing the subaddresses. If this cannot be determined, the master is determined by comparing the source address. Since both the transmission destination address and the transmission source address do not match, arbitration is always completed up to the transmission source address. In communication with the host device as the transmission destination (excluding general calls, which are special communications), the transmission source is the keyboard system, the transmission source is the panel system, and the transmission source is the keyboard / panel. Communication is given priority in the order of the composite system and the MIDI system, but this is also determined by a request for real-time performance.

Regarding the sub-address, in the host system, the sub-address “000” used when the category name of the communication partner device is the keyboard / panel system (keyboard system, panel system, or keyboard / panel composite system), and the MIDI system A sub-address “001” to be used is prepared. That is, when a keyboard / panel category name device is addressed, communication can be performed in preference to the MIDI system. The sub-addresses “010” to “111” are reserved for different bus formats or for future use. Further, when the slave address that is the addressed transmission destination matches and the master is not determined, the master is determined by comparing the master address that is transmitted next.
Also, eight sub-address ranges from “000” to “111” are given to the sub address of the keyboard system, the panel system, the keyboard / panel composite system, and the MIDI system. For this reason, each device of these category names can connect up to eight devices of the same category to the E bus system.

  By the way, in the E bus system, when communicating between devices, communication is performed with a communication protocol adapted to the category of the device, but the communication protocol of the general call that communicates with the devices of all categories is as follows. It is a common protocol. As shown in FIG. 5, specifically, when the category name communicated with the host system is a keyboard system, a panel system, or a keyboard / panel composite system, communication is performed using a standard protocol. If the category name to be communicated with the host system is MIDI, communication is performed using the MIDI protocol. In this case, since the category ID corresponding to the category name is given to the device, the communication protocol can be determined from the category ID of the addressed slave address. Since the host system (main controller) needs to perform communication using a communication protocol adapted to the category name to which the communication partner device belongs, as shown in FIG. Address for MIDI protocol. For example, when a host device and a MIDI device communicate with each other, the host device uses “0001 001” as its own address, and when the MIDI device becomes a master, The slave address to be addressed is “0001 001”. As a result, the host device and the MIDI device can communicate with each other using the MIDI protocol. When a host device and a keyboard device (panel system or keyboard / panel composite system) communicate with each other, the host device uses “0001 000” as its own address, and the keyboard system ( When a panel device or a keyboard / panel composite device becomes the master, the slave address to be addressed is “0001 000”. As a result, the host system device and the keyboard system (panel system or keyboard / panel composite system) device can communicate with each other using the standard protocol.

Next, FIG. 6 shows a packet data format in the E-bus system according to the present invention.
As shown in FIG. 6, the data format in the E bus system includes a standard data format having a total length of 5 bytes and a data format of extended data having a total length of 17 bytes. Is defined. In the data format of the standard data, a total of 5 of 1-byte transmission destination address (slave address) to be addressed, 1-byte transmission source address (master address), and 1-byte data 1, data 2, and data 3 respectively. Consists of bytes. Moreover, in the data format of the extended data, a total of 17 bytes of 1-byte transmission destination address (slave address), 1-byte transmission source address (master address), and 1-byte data 1 to data 15 are specified. It is composed of In this case, the transmission source address includes 1 bit of the dummy bit “0”, and the transmission destination address includes 1 bit of R / W. The data format of standard data is used in the common protocol, the standard protocol, and the MIDI protocol, and the data format of extended data is used in transferring a system exclusive message or the like in the MIDI protocol. Note that the transmission destination address and the transmission source address constitute the header part shown in FIG. 4, and the subsequent 3 bytes of data or 15 bytes of data constitute the data part. Note that data 1 in the standard data and extension data is an index indicating the type of data to be transferred. Specifically, the index indicates a command in each communication protocol. In this way, by unifying the packet length (or data byte length) in two ways, it is possible to simplify the processing in each device that performs communication. In an electronic musical instrument, a packet with 3 data bytes is optimal for exchanging ordinary commands except for exclusive. Also, by making the packet length of the normal command as short as about 5 bytes (10 bytes or less), the occupancy time of each packet on the bus is shortened, and input from the keyboard or panel of the electronic musical instrument The response time to can be shortened.

  Next, common protocol commands will be described. Since the common protocol is a communication protocol that can be used regardless of the category of the device that communicates with each other, each device does not determine that it is a common protocol, and does not process the category to which it belongs. Can handle common protocols. As described above, in the E bus system according to the electronic musical instrument bus system of the present invention, it is assumed that communication is performed between the host device as the main controller device 10 and another device. FIG. 7 shows the host reception and host transmission commands. The commands in the common protocol are all in the standard data format and are in the reverse order as shown in the figure, but the commands in the host transmission field include a category ID / sub address request. This command is a command for the host device to detect the address of the device connected to the E bus system, and can be called as a general call. Data 1 as an index in this command is “00h” (h indicates hexadecimal notation: 00h = 0000 0000), and data 2 and data 3 are also “00h”.

  When a category ID / sub-address request command is called from a host device as a general call, “0000 000” is a destination address, “0001 000” is a source address (see FIG. 5), and data is “00h”. A standard data command consisting of 1 to 3 is issued. General-categoed category ID / sub-address request commands are received by devices in all categories connected to the E-bus system, and each device receives a category ID / sub-address reply command indicated in the host reception column. To the host. This category ID / sub-address reply is a command for notifying a host device of an address unique to the own device. In order to issue the category ID / sub-address reply command, the destination address to be addressed is “0001 000”, the source address is the 7-bit address of the own device, the index data 1 is “00h”, and the data 2 is The machine category ID, data 3, transmits the standard data of its own sub-address. As a result, the host can know the devices connected to the E-bus system and their addresses. The category ID / sub-address request command is such that the host device makes a general call at the start of the operation of the E bus system. By this command, the device connected to the E bus system and its address are known. You can know the category name and communication protocol to use from the address you know. In this way, the host device can create the table shown in FIG. 5, and subsequent communication can be performed by setting an address in the created table. In principle, devices other than the host system communicate with the host system device, and a plurality of addresses assigned to the host system are addresses predetermined by the E bus system. Therefore, since devices other than the host system know in advance the address to be set when communicating, it is not necessary to create the table shown in FIG. Since the general call is a communication that is received by each device other than the host, if the general call is used when the category ID / sub-address is replied from each device, each device other than the host that receives it will ignore it. Processing is required. Therefore, in the E bus system according to the present invention, at the time of the reply, communication is performed using the standard address of the host as the transmission destination instead of the general call, and the processing in each device other than the host is simplified.

  The E bus start command in the host transmission column is a command that is generally called from the main controller device 10 and is a command for enabling the E bus system when the E bus system is started up. When a general call is made to the E bus start command, “0000 000” is the transmission destination address, “0001 000” is the transmission source address, index 1 is “01h”, data 2 is “00h”, and data 3 is The standard data “00h” is transmitted.

Next, host reception and host transmission commands of the standard protocol shown in FIG. 8 will be described. The standard protocol is a communication protocol that can be used when a host device (main controller) communicates with devices in the keyboard system, panel system, and keyboard / panel composite system categories. All commands in the standard protocol have a data format of standard data.
Of the commands in the host reception column in the standard protocol, the common protocol command is the same as the common protocol shown in FIG. 7 and will not be described. However, since this part is the same, the device operates in this device. Can be transmitted and received without switching between the standard protocol and the common protocol. The next SW OFF command and SW ON command are commands for transferring an OFF event and an ON event of a panel switch provided in the panel device to the host. For example, when the switch with the switch number n of the panel switch in the panel device is turned off, the transmission destination address is “0001 000” indicating the host, and the transmission source address is the address “0011 aaa” (“aaa” of the panel device. "Is the sub address of the panel device), and the SW OFF command in which the index data 1 is" 6xh ", the data 2 is switched off n (8 bits), and the data 3 is a dummy" 00h " publish.

  When the switch of the panel switch switch number m in the panel device is turned ON, the transmission destination address is “0001 000” indicating the host, and the transmission source address is the address “0011 bbb” (“bbb” of the panel device. "Is the sub address of the panel device), SW 1 command with index 1 as" 7xh ", data 2 as switch number m (8 bits), and data 3 as dummy" 00h " Is issued. In any command, “xh” indicates a port number, and the switch number is 8 bits. Therefore, it is possible to issue SW OFF commands and SW ON commands for 16 ports × 256 panel switches. it can.

  The keyboard OFF command and keyboard ON command in the host reception column in the standard protocol are commands for transferring the note-on event and note-off event of each key in the keyboard device to the host. Here, when the key corresponding to the note number n in the keyboard device is note-off, the transmission destination address is “0001 000” indicating the host, and the transmission source address is the address “0010 aaa” (“ “aaa” is the sub address of the keyboard device), the index data 1 is “8vh”, the data 2 is the note-off note number n (8 bits), and the data 3 is the upper 8 bits of the velocity An OFF command is issued. Note that “vh” is the low-order 4 bits of velocity, and the velocity information having a total of 12 bits is transferred, and the high-order 7 bits are MIDI compatible.

  When the key corresponding to the note number m in the keyboard device is turned on, the transmission destination address is “0001 000” indicating the host, and the transmission source address is the address “0010 bbb” (“bbb” of the keyboard device. “Is the sub address of the keyboard device), the index data 1 is“ 9 vh ”, the data 2 is note-on note number m (8 bits), and the data 3 is the upper 8 bits of velocity ON A command is issued. In this command, velocity information having a total of 12 bits is transferred as in the keyboard OFF command, and the upper 7 bits are MIDI compatible. Further, since the note number is 8 bits in any command, a keyboard OFF command and a keyboard ON command corresponding to 256 notes can be issued. Here, in the keyboard OFF command and the keyboard ON command, the port number is deleted and the velocity information is set to 12 bits. The capture of the keyboard performance has a higher resolution than the MIDI velocity because of processing of touch curves and the like. This is because a 12-bit velocity resolution is required.

  The polyphonic aftertouch command for transferring the value of polyphonic aftertouch (aftertouch for each key) on the keyboard device in the host reception column in the standard protocol has the transmission destination address “0001 000” indicating the host, and the transmission source address is The address of the keyboard device is “0010 aaa” (“aaa” is the subaddress of the keyboard device), the index data 1 is “Axh”, and the data 2 is the note number n (8 bits) to which the touch is applied. , Data 3 is an 8-bit after value. Since “xh” is a port number, a 16-port polyphonic aftertouch command can be issued.

  In the standard controller, the continuous controller command for transferring the manipulated value such as the volume or wheel in the panel device of the host reception column in the standard protocol has the transmission destination address “0001 000” indicating the host, and the transmission source address is The address of the panel device is “0011 aaa” (where “aaa” is the sub address of the panel device), the index data 1 is “Bxh”, the data 2 is the type of controller such as volume or wheel (8 bits), Data 3 is an operation value of the 8-bit controller. Since “xh” is a port number and the type is 8 bits, 16 ports × 256 continuous controller commands can be issued.

  In the JOG controller command for transferring the operation value operated in the jog controller such as the rotary encoder in the panel device of the host reception column in the standard protocol, the transmission destination address is “0001 000” indicating the host, and the transmission source address is The address of the panel device is “0011 aaa” (“aaa” is the sub-address of the panel device), the index data 1 is “Cxh”, the data 2 is the jog controller type (8 bits), and the data 3 is the controller 2 is a relative value (8 bits) of the two's complement of the operation value. Since “xh” is a port number and the type is 8 bits, 16 ports × 256 JOG controller commands can be issued.

  The after touch command for transferring the value of the after touch on the keyboard device in the host reception field in the standard protocol (the after touch common to a plurality of keys of one key) is set to “0001 000” indicating the host as the transmission destination address. The original address is the address “0010 aaa” of the keyboard device (“aaa” is the sub-address of the keyboard device), the index data 1 is “Dxh”, the data 2 is the upper 8 bits of the touch value, and the data 3 is The lower 8 bits of the touch value. Since “xh” is a port number, a 16-port aftertouch command can be issued. The touch value transferred by the after touch command is a touch value applied to all of the notes that are turned on by a plurality of notes in the keyboard device as the master (sender).

  In addition, a 16-bit continuous controller command for transferring an operation value such as a volume or a wheel in a panel device in the host reception column in the standard protocol has a transmission destination address “0001 000” indicating the host, and is transmitted. The original address is the address “0011 aaa” of the panel device (“aaa” is the sub address of the panel device), the index data 1 is “Exh”, the data 2 is the upper 8 bits of the controller operation value, the data 3 is the lower 8 bits of the operation value of the controller. Since “xh” is a port number, a 16-bit 16-bit continuous controller command can be issued. Note that a keyboard / panel composite device can transmit commands from both the keyboard device and the panel device. Further, the continuous controller command and the jog controller command may be transmitted from the keyboard device.

Next, commands in the host transmission field in the standard protocol will be described. First, the common protocol command in the host transmission column is the same as the common protocol shown in FIG.
The LED control command in the host transmission column is a command for the host to control the luminance of the group to which the LED (Light Emitting Diode) provided in the panel device belongs. The LED control command has an address “0011 aaa” (“aaa” is a subaddress of the panel device) of the panel device whose luminance is controlled as the transmission destination address, “0001 000” indicating the host as the transmission source address, and an index. The data 1 is “6xh”, the data 2 is the group number (8 bits) for controlling the brightness, and the data 3 is the 8-bit LED brightness value that is the brightness control value. Since “xh” is a port number, a 16-port LED control command can be issued. However, since the luminance of the group “00h” is the minimum (corresponding to OFF) and the luminance of the group “FFh” is the maximum (corresponding to ON), the luminance of the group cannot be changed. .

  The LED command in the host transmission column is a command for the host to distribute the LEDs provided in the panel device into groups. The LED command has an address “0011 aaa” (“aaa” is a sub-address of the panel device) of the panel device whose destination address is controlled, an index of “0001 000” indicating the host, and an index. The data 1 is “7xh”, the data 2 is an 8-bit LED number assigned to the group, and the 8-bit group number is assigned the data 3. Since “xh” is a port number and the LED number is 8 bits, 16 port × 256 LED commands can be issued.

Here, the LED control command and how to use the LED command will be described. When the host transmits an LED command for distributing the LED “i” to the group “FFh” to the panel device, the panel device that has received this LED command receives the LED number “i”. "" LED comes on. When an LED command for allocating the LED “j” to the group “00h” is transmitted, the panel device that has received the LED command turns off the LED with the LED number “j”.
In addition, first, an LED control for setting the luminance of the group “01h” to “00h” (minimum value) is transmitted from the host to the panel device, and a plurality of LED numbers for a desired plurality of LEDs are assigned to the group “01h”. This LED command is sent, and finally the LED control for setting the brightness of the group “01h” to “FFh” (maximum value) is sent, so that the plurality of LEDs of the panel device can be turned on simultaneously. become.

  The keyboard LED control command in the host transmission column is a command for the host to control the luminance of the group to which the LED (performance guide LED) provided in each key of the keyboard device belongs. The keyboard LED control command has an address “0010 aaa” (“aaa” is a sub-address of the keyboard device) of the keyboard device whose luminance is controlled as the transmission destination address, and “0001 000” indicating the host as the transmission source address. The index data 1 is “8xh”, the data 2 is the group number (8 bits) whose brightness is controlled, and the data 3 is the 8-bit LED brightness value which is the brightness control value. Since “xh” is a port number, a 16-port keyboard LED control command can be issued. However, since the luminance of the group “00h” is minimum (corresponding to OFF) and the luminance of the group “FFh” is maximum (corresponding to ON), the luminance cannot be changed.

  The keyboard LED command in the host transmission column is a command for the host to distribute the LEDs provided in the keyboard device into groups. The keyboard LED command has an address “0010 aaa” (“aaa” is a subaddress of the keyboard device) of the keyboard device whose transmission destination address is controlled, a source address “0001 000” indicating the host, an index, The data 1 to be assigned is “9xh”, the note number (8 bits) of the key provided with the LED for assigning the data 2 to the group, and the 8-bit group number to which the data 3 is assigned. Since “xh” is a port number and the note number is 8 bits, 16 port × 256 keyboard LED commands can be issued. The manner of controlling the keyboard LED by the keyboard LED control command and the keyboard LED command is the same as the manner of controlling the LED of the panel device by the LED control command and the LED command. According to the keyboard OFF command and the keyboard ON command, the maximum number of keys of each keyboard device is 256. Therefore, the port number in the keyboard LED control command and the keyboard LED command is, for example, a plurality of LEDs of a plurality of colors for each key. Can be used to control the color, or can be used to control the position of the LED by providing LEDs at a plurality of locations of each key.

  In addition, the continuous controller command for controlling the operation values of the electric volume, electric wheel, and the like in the panel device in the host transmission column in the standard protocol from the host is the address “0011 aaa” (“ "aaa" is a sub-address of the panel device), the transmission source address is "0001 000" indicating the host, the index data 1 is "Bxh", and the data 2 is the type of controller such as an electric volume or electric wheel (8 bits), data 3 is the control value of the 8-bit electric controller. Since “xh” is a port number and the type is 8 bits, 16 ports × 256 continuous controller commands can be issued.

  Also, the JOG controller command for controlling the operation value of the electric jog controller such as the rotary encoder in the panel device in the host transmission column in the standard protocol from the host is the address “0011 aaa” (“aaa” of the panel device whose transmission destination address is controlled. ”Is the sub address of the panel device), the transmission source address is“ 0001 000 ”indicating the host, the index data 1 is“ Cxh ”, the data 2 is the electric jog controller type (8 bits), the data 3 is a 2's complement relative value (8 bits) for controlling the electric controller. Since “xh” is a port number and the type is 8 bits, 16 ports × 256 JOG controller commands can be issued.

  In addition, a 16-bit continuous controller command for controlling the operation values of the electric volume and electric wheel in the panel device in the host transmission column in the standard protocol from the host is the address “0011 aaa” of the panel device whose transmission destination address is controlled. "(Aaa" is the sub-address of the panel device), the transmission source address is "0001 000" indicating the host, the index data 1 is "Exh", and the data 2 is the upper control value of the electric controller 8 bits and data 3 are the lower 8 bits of the control value of the electric controller. Since “xh” is a port number, a 16-bit 16-bit continuous controller command can be issued.

  Next, the MIDI protocol command shown in FIG. 9 will be described. The MIDI protocol is a communication protocol that can be used when a host device (main controller) communicates with a MIDI device. The command in the MIDI protocol uses standard data and extended data formats. Note that in the MIDI protocol, commands for host transmission and host reception are common, and only the transmission destination address and the transmission source address differ between host reception and host transmission. That is, in the case of a host reception command, the transmission destination address is “0001 001” which is an address for the host's MIDI protocol, and the transmission source address is the address of the MIDI device to be transmitted. In the case of a host transmission command, the transmission destination address is the address of the MIDI device, and the transmission source address is “0001 001”, which is the address for the host's MIDI protocol. In each command of the MIDI protocol shown in FIG. 9, the transmission destination address and the transmission source address are set as described above, and in the following description of the command, only the data format and data portion of each command will be described.

The common protocol commands in the MIDI protocol are the same as those in the common protocol shown in FIG.
The system exclusive (Sys EX) start and continuation command and the system exclusive (Sys EX) end or one packet command both have a data format of the extended mode and are 17 bytes long. In the system exclusive (Sys EX) start and continuation command, “4ih”, which is an index indicating the start and continuation of the system exclusive, is set as data 1, and tone parameters and sequences are determined by data of 1 byte for each of data 2 to data 15.・ Data etc. are transferred. For the system exclusive (Sys EX) end or 1 packet command, “5ih”, which is an index indicating the end of system exclusive or 1 packet, is set as data 1, and in the case of 1 packet, 1 packet of 1 packet Data is transferred byte by byte.
In MIDI, the start of system exclusive is indicated by “F0h” and the end of “F0h”, but in the E bus system, the start of system exclusive is “5ih” instead of “4ih”, as described above. “F0h” and “F7h” are not used. “Ih” indicates a MIDI port number for transmitting the system exclusive.

The song position (Song Pos) command is a command for informing the position where performance is started, and is in a standard data format. In the song position command, the index “6ih” is data 1, data 2 is the LSB of the performance start position pointer, and data 3 is the MSB of the performance start position pointer. In MIDI, the message of the song position pointer is indicated by “F2h”, and data 2 and data 3 are compatible with this message.
The MIDI port select command is a command for selecting a current MIDI port number (a MIDI port number to which a note-on message and a note-off message are transmitted / received), and has a data format of standard data. In the MIDI port select command, “7ih” as an index is set as data 1, data 2 is set as “00h”, and data 3 is set as “00h”. For example, when a MIDI port select command is transmitted from the host to the MIDI device, the received MIDI device sets the current MIDI port number to the value “ih” included in the index. Note that the MIDI standard does not define a port select message (“F5h” may be used in implementation). The MIDI port select command corresponds to the MIDI timepiece message function in MIDI.

  Two MIDI compatible (note, vel) commands are compatible with a note-on message and a note-off message in MIDI, and have a data format of standard data. In these commands, data 1 is “8nh”, which is a MIDI note-off index, data 2 is a MIDI-compatible 8-bit note-off note number, and data 3 is MIDI-compatible 8-bit off-velocity. Is a note-off command. Also, if data 1 is “9nh”, which is a note-on index in MIDI, data 2 is an 8-bit note-on note number compatible with MIDI, and data 3 is an 8-bit velocity compatible with MIDI. This is a note-on command. Note that data 1 is “9 nh”, which is a note-on index in MIDI, data 2 is 8-bit note-off note number compatible with MIDI, and data 3 is “00h” (velocity is zero). Things may be used as note-off commands. “Nh” is a MIDI channel number.

The MIDI compatible (note, Aft) command is compatible with a polyphonic key pressure message in MIDI, and is a command that can send independent after-touch information for each key. This command is a standard data format. In this command, data 1 is “Anh”, which is an index of polyphonic key pressure in MIDI, data 2 is a note number for sending MIDI compatible 8-bit after touch information, and data 3 is MIDI compatible 8 It is a bit touch value. “Nh” is a MIDI channel number.
A MIDI compatible (CtnNo., Value) command is compatible with a control change message in MIDI, and is a command capable of sending information on a controller such as a damper pedal, volume, modulation, and wheel. This command is a standard data format. In this command, data 1 is “Bnh” which is an index of MIDI control change, data 2 is a MIDI compatible 8-bit control number indicating the control function, and data 3 is a MIDI compatible 8-bit control value. It is said. “Nh” is a MIDI channel number.

The MIDI compatible (PrgNo., 00) command is compatible with a program change message in MIDI, and is a command for switching timbres. This command is a standard data format. In this command, data 1 is “Cnh” which is an index of program change in MIDI, data 2 is an 8-bit program number compatible with MIDI, and data 3 is not required in a program change message in MIDI. Therefore, it is set to “00h”. “Nh” is a MIDI channel number.
The MIDI compatible (Aft, 00) command is compatible with channel pressure in MIDI, and is a command for switching timbres. This command is a standard data format. In this command, data 1 is “Dnh”, which is an index of channel pressure in MIDI, data 2 is an 8-bit after-touch value compatible with MIDI, and data 3 is required for a program change message in MIDI. Because it is not, it is set to “00h”. “Nh” is a MIDI channel number. Since this command is a command for sending representative after-touch information, if a plurality of notes are turned on, all the notes-on after-touch information are used.

  The MIDI compatible (BendL, H) command is compatible with a pitch bend message in MIDI, and is a command for sending information on a pitch bender composed of a wheel, a joystick, and the like. This command is a standard data format. In this command, data 1 is set to “Enh”, which is an index of pitch bend in MIDI, data 2 is LSB of 8-bit pitch bend value compatible with MIDI, and data 3 is 8-bit pitch of MIDI compatible. The MSB of the bend value is used. “Nh” is a MIDI channel number.

  In MIDI, statuses “F0h” to “F7h” are defined. However, the statuses “F4h” and “F5h” are undefined. As described above, the system exclusive start and end statuses “F0h” and “F7h” in MIDI are not used after being converted to the indexes “4ih” and “5ih” of the E bus system. Similarly, the status “F2h” in MIDI is converted to the E bus system index “6xh”. If the status “F5h” in MIDI is defined as MIDI Time Piece, the status is changed to the E bus system index “7xh”. Convert. In this way, some statuses of “F0h” to “F7h” are converted. This is because the number of bytes is increased by 1 byte for some statuses in the standard data format, or This is because the MIDI port number can be designated by the increased bytes. In the MIDI standard, the most significant bit of each byte of a message is used to determine whether the byte is a status byte or a data byte. Since it is always a command, it is not necessary to use the most significant bit for the same purpose. Therefore, in the above-described MIDI protocol, “00h” to “7Fh” that are out of the MIDI status byte are used as commands for common protocols and commands for extending MIDI.

Further, the F1 (MIDI Timecode Quater Frame) command is a command for sending hour / minute / second information in the MIDI time code. This command is a standard data format. In this command, data 1 is “Fih”, which is an index, data 2 is MIDI time code quarter frame status “F1h”, and data 3 is MIDI compatible 8-bit hour / minute / second. Value.
Furthermore, the F3 (Song Select) command is a command for selecting a song stored in a song memory or a storage medium. This command is a standard data format. In this command, data 1 is “Fih” which is an index, data 2 is “F3h” which is a song select status in MIDI, and data 3 is a MIDI compatible 8-bit song number.

  Furthermore, the F6 (Tune Request) command is a command for tuning a MIDI device having an auto-tuning function. This command is a standard data format. In this command, data 1 is set to “Fih” which is an index, data 2 is set to “F6h” which is a status of a tune request in MIDI, and data 3 is set to “00h” because it is not required in MIDI. .

Furthermore, a system real-time message command is a command that sends a message that needs to be processed in real time. This command is a standard data format. In this command, data 1 is set as “Fih”, which is an index, data 2 is one of “F8h” to “FFh” which is the status of a system real-time message in MIDI, and data 3 is not required in MIDI. Therefore, it is set to “00h”. Data 2 is as follows.
If the function is a timing clock, status “F8h”
Status “FAh” if the function is set to start
If the function is set to continue, the status “FBh”
If the function is stopped, the status is “FCh”
Status “FFh” if the function is a system reset
The statuses “F9h” and “FDh” are undefined, and the status “FEh” is defined as active sensing, but the active sensing (“FEh”) is not used in the E-bus system according to the present invention. . Note that in a command in which the above data 1 is “Fih”, “ih” indicates a MIDI port number to which the command is transmitted.

Next, the E bus activation procedure of the E bus system according to the present invention is shown in the flowchart shown in FIG.
When power is turned on in the E bus system (step S1), power is supplied to all devices connected to the E bus system via the four power lines of the E bus 11. Here, the host (main controller device 10) sets the initial clear line in the E bus 11 to the L level. As a result, the device connected to the E bus system stops functioning and is reset, and the hardware of the device is initialized (step S2). Next, the host (main controller device 10) sets the initial clear line in the E bus 11 to the H level and activates the device connected to the E bus system. Thereby, the software is initialized in the device connected to the E bus system (step S3). Here, the host (main controller device 10) transmits the “E bus start” command shown in FIG. 7 by a general call (step S4). Each device connected to the E-bus system receives this “E-bus start” command and starts to operate, whereby the E-bus system starts to operate. The table using the category ID / sub-address request command in the host system is performed immediately after the “E bus start” command is sent.

Next, FIG. 11 shows a flowchart of host reception processing in the E-bus system according to the present invention.
In the host reception processing shown in FIG. 11, when the host (main controller device 10) receives a signal from the E bus 11, it is determined whether the destination address received in step S10 is “10h” or “12h”. In this case, the transmission destination address is the address of the host whose address is specified because it is host reception. However, the host address determined in step S10 includes 1 bit for R / W that is always set to “0”. If it is determined that the received transmission destination address is “10h” (= “0001 0000”), the host address of the standard protocol is designated, and the process proceeds to step S11 where the transmission of the transmission source address and the data are performed. A standard protocol reception process for receiving a data portion consisting of 1 to 3 is performed. If a valid signal is received, an acknowledge is returned for each byte. In this standard protocol reception process, for example, the host receives a command such as keyboard OFF or keyboard ON from the keyboard device, or receives a command such as SW ON or continuous controller from the panel device.

  Further, when the received transmission destination address is determined to be “12h” (= “0001 0010”), since the host address of the MIDI protocol is designated, the process branches to step S12 to receive the transmission source address. A MIDI protocol reception process for receiving a data portion including data 1 to data 3 or data 1 to data 15 is performed. Furthermore, if a valid signal can be received, an acknowledge is returned for each byte. When the reception process in step S11 or step S12 ends, the host reception process also ends. In this MIDI protocol reception process, the host receives a MIDI message command such as note-on or note-off from a MIDI input / output device, for example.

Next, FIG. 12 shows a flowchart of host transmission processing in the E-bus system according to the present invention.
In the host transmission process shown in FIG. 12, when the host (main controller device 10) transmits to the E bus 11, the upper 4 bits of the transmission destination address specified in step S20 are “2h” to “4h”. Or “5h”. In this case, the upper 4 bits of the destination address are the category ID of the destination device addressed by the host because it is host transmission. If it is determined that the upper 4 bits of the transmission destination address are “2h” to “4h” (= “0001” to “0100”), the keyboard system, the panel system, or the keyboard / panel composite system device This means that it is the destination device. Since the communication protocol of these categories of devices is the standard protocol as shown in FIG. 5, the process proceeds to step S21, and the source address “0001 000” which is the host address in the standard protocol is added, and then the data A standard protocol transmission process is performed in which a data portion consisting of 1 to 3 is transmitted. In this standard protocol transmission processing, the host transmits, for example, an LED command (a command for distributing LED “i” to the group “FFh”) to turn on the LED of LED number i to the panel device.

  When the upper 4 bits of the transmission destination address to be transmitted are determined to be “5h” (= “0101”), the MIDI device is the transmission destination device. As shown in FIG. 5, the device in the MIDI category has a communication protocol of the MIDI protocol. Therefore, the process branches to step S22 and a source address “0001 001” which is the host address in the MIDI protocol is added. Next, a MIDI protocol transmission process is performed in which a data portion including data 1 to data 3 or data 1 to data 15 is transmitted. When the transmission process in step S21 or step S22 ends, the host transmission process also ends. In this MIDI protocol transmission process, the host transmits a MIDI message command such as note-on or note-off to, for example, a MIDI sequencer device.

Next, FIG. 13 shows a flowchart of keyboard device transmission / reception processing in the E-bus system according to the present invention.
In the keyboard transmission / reception process shown in FIG. 13, since the communication protocol is the standard protocol, the standard protocol transmission / reception process is performed in step S30. In this standard protocol transmission processing, “0001 000”, which is the address of the standard protocol in the host, is specified as the destination address to be addressed, and the address of the own device is specified as the source address for transmission. The address of the own device is a 3-bit address set to the own device with the category ID “0010”. Following these addresses, a data part consisting of data 1 to data 3 is transmitted.
Further, in the standard protocol reception process, when the destination address specified by the address matches the address of the own device, the subsequent transmission source address and the data part including data 1 to data 3 are received. In this case, “0001 000”, which is a standard protocol address in the host, is designated as the source address.
In the standard protocol, the panel system and keyboard / panel composite system devices also communicate, but the transmission / reception process at this time is the same as the above-described keyboard transmission / reception process except that the category ID is different.

Next, FIG. 14 shows a flowchart of MIDI device transmission / reception processing in the E-bus system according to the present invention.
In the MIDI transmission / reception process shown in FIG. 14, since the communication protocol is the MIDI protocol, the MIDI protocol transmission / reception process is performed in step S40. In this MIDI protocol transmission processing, “0001 001”, which is the MIDI protocol address in the host, is specified as the destination address to be specified for transmission, and the own address is specified as the source address for transmission. The address of the own device is a 3-bit address set to the own device with the category ID “0101”. Following these addresses, a data portion consisting of data 1 to data 3 or data 1 to data 15 is transmitted.
Also, in the MIDI protocol reception process, when the addressed destination address matches the address of its own device, the subsequent transmission source address and the data part consisting of data 1 to data 3 or data 1 to data 15 are received. To do. In this case, “0001 001”, which is the address of the MIDI protocol in the host, is designated as the source address.

  By the way, the host generates a MIDI note-on message in response to a keyboard-on command from the keyboard, controls the tone generation in the tone generator unit in response to the note-on message, and transmits the note-on message via the E bus. To the MIDI device. Also, when a SW ON command is received from the panel, selection of tone data for sound generation, editing of tone data, recording / playback of music data for automatic performance, and recording of music data according to the type of the SW ON command Processing such as editing, setting change of the own device, setting change of each device connected to the E bus is performed. Further, when selecting timbre data, for example, an LED command is transmitted to the panel device to light the LED corresponding to the selected timbre data, and a program change message corresponding to the selection is sent to the MIDI device. To do. Furthermore, when the music data is played back by the host (at the time of automatic performance), the tone generation of the tone generator unit is controlled in accordance with the sequentially played back MIDI messages, and the MIDI message is sent to the MIDI via the E bus. Send to device.

According to the present invention described above, communication between devices constituting an electronic musical instrument can be performed through a bus system. In this case, the data signal transmitted from the master is given a unique address to the device as the transmission destination, and this address is one of the category information indicating the category of the device and the device of the same category. It consists of a sub-address that identifies one device. Thereby, it becomes possible to communicate between devices of various categories through the bus system. Therefore, in the electronic musical instrument, for example, when a keyboard is newly developed as a device, an electronic musical instrument having a newly developed keyboard can be configured by simply connecting the keyboard to the electronic musical instrument bus system. In this case, other categories of devices such as panel and host devices can be used as they are.
Furthermore, when a device is added as a function is added, an electronic musical instrument to which a new device is added can be configured simply by connecting the added device to the electronic musical instrument bus system. As a result, the product development cost can be significantly reduced. In addition, the function can be added in a short time.
Thus, in the present invention, each device can be used for other products and can be developed separately for each device.

  Furthermore, by unifying the main packet length to the first predetermined length between the keyboard or panel operation input device and the MIDI device, the reception process in each device can be simplified. Furthermore, the system exclusive communication efficiency is not lowered by performing communication with the second predetermined length longer than the first predetermined length only for the system exclusive which tends to have a long byte length. Furthermore, it is possible to control a plurality of display elements at the same time, and when there is not much change in the set of display elements to be controlled at the same time, the number of commands for display control can be reduced. Furthermore, the MIDI message can be transmitted and received in the electronic musical instrument bus system without affecting the MIDI message.

In the above description, each LED provided in the keyboard device or the panel device belongs to any one group, but one LED may belong to a plurality of groups. . In that case, the control value of the LED may be the maximum value, the minimum value, or the combined value of the control values of the group to which the LED belongs. In the above description, “host system”, “keyboard system”, “panel system”, and “MIDI system” are shown as devices connected to the E bus, but other types of devices may be connected. . Further, in the above description, three protocols of “common protocol”, “standard protocol”, and “MIDI protocol” are shown as data protocols on the E bus, but other protocols may be used.
The E bus system according to the present invention described above is based on an I-SCA (I ² C) bus. The points not mentioned in the E bus system conform to the I ² C bus.

1 electronic musical instrument, 10 main controller device, 10a main board, 11 E bus, 12, 13 panel device, 12a panel board, 14, 15 keyboard device, 14a keyboard board, 16 MIDI device, 16a board, 17 branch board, 21 bus , 22, 23, 24 Sound source unit, 25, 26 I / O unit, 31 bus, 32 sound system, B1-B6 buffer, Rp pull-up resistor, TR1-TR6 transistor

Claims (2)

A bus system built in an electronic musical instrument comprising at least a serial clock line to which a clock is transferred and a serial data line to which a data signal synchronized with a clock signal of the serial clock line is transferred,
Between a plurality of types of devices connected to the bus system, data is transmitted and received through the bus system,
Each of the devices has a unique address,
The device includes a host device, an arbitrary operation input device that can be attached to and detached from the bus system, and an arbitrary operation input device that can be attached to and detached from the bus system. Including MIDI devices,
The address includes category information indicating a category of the device, and a sub-address that specifies any one of the devices of the same category.
The transmission / reception of the data is performed by a fixed-length packet in which a header part including at least a transmission destination address and index information indicating a type of data to be transmitted are added to the data,
The host device identifies whether the other device that transmits and receives the data is the operation input device or the MIDI device based on the category information of the address,
Between the host device and the operation input device, the fixed-length packet including index information indicating the type of control command corresponding to the control / operation content to be transmitted is transmitted to the bus system using the first protocol. And
Between the host device and the MIDI device, the second protocol includes index information indicating the type of the MIDI message corresponding to the status byte of the MIDI message to be transmitted and the data byte of the MIDI message A bus system for an electronic musical instrument characterized in that the MIDI message is converted into the fixed-length packet and transmitted to the bus system as packet data. A bus system built in an electronic musical instrument comprising at least a serial clock line to which a clock is transferred and a serial data line to which a data signal synchronized with a clock signal of the serial clock line is transferred,
Between a plurality of types of devices connected to the bus system, data is transmitted and received through the bus system,
Each of the devices has a unique address,
The device includes a host device, an arbitrary operation input device that can be attached to and detached from the bus system, and an arbitrary operation input device that can be attached to and detached from the bus system. Including MIDI devices,
The address includes category information indicating a category of the device, and a sub-address that specifies any one of the devices of the same category.
The transmission / reception of the data is performed by a fixed-length packet in which a header part including at least a transmission destination address and index information indicating a type of data to be transmitted are added to the data,
The host device identifies whether the other device that transmits and receives the data is the operation input device or the MIDI device based on the category information of the address,
Between the host device and the operation input device, in the first protocol, the fixed-length packet including index information indicating the type of control command corresponding to the control / operation content is received from the bus system,
Between the host device and the MIDI device, the fixed-length packet including index information indicating the type of the MIDI message is received from the bus system by the second protocol, and the received fixed-length packet is received by the reception device. A bus system for an electronic musical instrument characterized in that a status byte corresponding to the index information of the fixed-length packet is converted into a MIDI message having the received fixed-length packet data as a data byte.

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