JP2678974B2 - Musical sound wave generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound source processing system in a musical tone waveform generating apparatus, and more particularly to a musical tone waveform generating apparatus for executing a sound source processing in which a plurality of sound source systems are mixed for each sounding channel as software processing. Regarding

[0002]

2. Description of the Related Art Various electronic musical instruments with good performance have been realized by the development of digital signal processing technology and LSI processing technology.

Since the musical tone waveform generator of an electronic musical instrument requires a large amount of high-speed digital calculation, conventionally, a dedicated tone generator circuit has realized in hardware an architecture equivalent to a tone generation algorithm based on the required tone generator method. Was composed by. Therefore, the hardware scale becomes large, and it is difficult to freely change the tone generator system. Further, when such a musical tone waveform generator is realized as an electronic musical instrument, the processing for the performance information and the tone generator are performed. The control for synchronizing both the processes for (1) and (2) has become complicated, resulting in a great increase in cost in its development.

On the other hand, in recent years, many high-performance microprocessors for performing general-purpose data processing have been realized, and a musical tone waveform generator for performing sound source processing by software using such a microprocessor. It is also possible to realize.

In such a system, for example, a processor normally executes a performance information processing program to process performance information generated from a keyboard or the like based on a performance operation, and interrupts at a predetermined time interval. The processing is transferred to a sound source processing program to generate a musical sound. After that, when the execution of the sound source processing program is completed, the interrupt is released and the execution of the performance information processing program is resumed.

In the software sound source processing as described above, in order to be able to generate a plurality of musical tones at the same time, in general,
Time division processing is performed on a plurality of sound generation channels during a processing cycle such as interruption at predetermined time intervals. Then, by executing a sound source processing program having a different sound source method for each sound generation channel, a PC can be used for a certain tone color.
The M tone is a modulation tone for different tone colors, or the PCM tone is for even tone channels and the modulation tone is for odd tone channels when a tone tone has a different tone color. It is also possible to generate

In such a case, in general, the sound source system number and the like are stored in a memory for each sounding channel,
Each time the processing timing of each sound generation channel is approached, control is performed such that the sound source system number and the like stored corresponding to that sound generation channel is identified and the sound source processing program of the corresponding sound source system is executed.

Here, in order to improve the performance of the musical instrument,
When there is a request to increase the number of sounding channels that can be sounded at the same time, it is necessary to execute as many program instructions as possible during the processing cycle.

[0009]

Therefore, in the processing of each tone generation channel, it is necessary to reduce instructions having a long operation cycle such as branch instructions as much as possible. However, when it is desired to generate a tone with a different tone generator method for each sounding channel, a branch instruction is executed to identify the tone generator method each time the processing timing of each sounding channel is approached, as in the above-described conventional example. Therefore, there is a possibility that the processing for all the sound generation channels cannot be completed within one processing period.

In order to prevent this, it is necessary to take measures such as decreasing the sampling frequency for generating the musical tone and increasing the time interval of the sound source processing, and as a result, the sampling frequency for generating the musical tone is reduced. Then, the maximum frequency of the generated musical sound becomes low and the sound quality is deteriorated.

An object of the present invention is to make it possible to reduce the number of processing instructions for each sounding channel when the sound source processing in which a plurality of sound source systems are mixed for each sounding channel is executed as a software process.

[0012]

SUMMARY OF THE INVENTION According to the present invention, a plurality of sound source systems, for example, P, are provided at predetermined time intervals for each of a plurality of sounding channels, for example, for each of 8 channels.
It is premised on a musical tone waveform generator including a program executing means for executing a sound source processing program of an arbitrary sound source method among a CM method, a DPCM method, an FM method, a TM method and the like to generate a tone signal. In this case, a plurality of processor configurations may be able to process more pronunciation channels.

First, there is provided a sound source processing program storage means such as a ROM for storing a plurality of sets of sound source processing programs continuously executed for all sound generation channels for each combination of sound source systems of all sound generation channels. The means includes, for example, a sound source processing program for continuously generating musical sound in PCM method for all eight channels, and a sound source processing for continuously generating musical sound in a mode in which PCM method, TM method and the like are mixed for each sounding channel. Multiple sets such as programs are stored.

Next, there is provided an execution program storage means such as a RAM for storing a sound source processing program which is continuously executed by the program execution means for all the sound generation channels at the above-mentioned predetermined time intervals. In the case of a multi-processor configuration as described above, it is provided for each processor.

Further, there is provided a tone generator processing program transfer control means for reading out an arbitrary set of tone generator processing programs which are continuously executed for all sound generation channels from the storage program memory means and transferring them to the execution program memory means. In the case of a multiple processor configuration as described above,
The control means transfers to the execution program storage means of each processor.

[0016]

When the performer sets a tone color or turns on the power of the apparatus, the sound source processing program transfer control means continuously executes the sound source channel for all sound generation channels from the storage program storage means. An arbitrary set of processing programs is read out and transferred to the execution program storage means. Then, the program executing means collectively executes the sound source processing program stored in the execution program storing means for all the sounding channels when generating the musical sound of each sounding channel at every predetermined time interval.

As a result, it is not necessary to perform the discrimination process of which sound source method is used to generate a musical tone for each sounding channel, and the number of branch instructions can be reduced.
It is possible to improve the performance of the musical instrument such as increasing the number of sounding channels that can be sounded at the same time.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. <Structure of this Embodiment> FIG. 1 is a diagram showing the entire structure of this embodiment, in which one chip except for the external memory 116 is constituted by two CPUs (central processing unit) of a master and a slave. While exchanging information, sound source processing for musical tone creation is shared.

In FIG. 1, first, in the external memory 116, a tone control parameter such as a target value of an envelope value and a tone waveform in a PCM (pulse code modulation) system or a tone difference waveform in a DPCM (differential pulse code modulation) system. , And programs for processing various sound sources are stored.

On the other hand, a master CPU (hereinafter, abbreviated as MCPU) 101 and a slave CPU (hereinafter, abbreviated as SCPU) 102 access each of the above-mentioned data in an external memory 116 and share them to perform sound source processing. . These CPUs
Both share the waveform data and the like in the external memory 116, so that there is a possibility that contention will occur when reading data from the external memory 116. for that reason,
Each of the MCPU 101 and SCPU 102 has an MCPU external memory access address latch unit 103 and an SCPU external memory access address latch unit 104,
By outputting the address signal for external memory access and the external memory control data from the access address conflict avoidance circuit 105 from the output terminals 111 and 112, the MCPU
The conflict between the address from 101 and the address from SCPU 102 can be avoided.

External memory 1 based on the above address designation
The data read from 16 is input to the external memory selector unit 106 from the external memory data-in terminal 115. The external memory selector unit 106, based on the control signal from the access address conflict avoidance circuit 105, sends the read data to the MCPU1 through the data bus MD.
01 through the data bus SD and S
Separated into data input to CPU 102,
Input to U 101 and SCPU 102. Thus, data conflict can be avoided.

After that, for each data, MCPU
In 101 and SCPU 102, after sound source processing is performed by software, all sound channels are accumulated and Le
Left output terminal 113 and Ri of the ft D / A converter unit 107
From the right output terminal 114 of the ght D / A converter unit 108, the left channel left analog output and the right channel right analog output are respectively output as musical tone signals.

Next, FIG. 2 is a block diagram showing the internal structure of the MCPU 101. In the figure, a program memory 201 is composed of a ROM part for storing a program corresponding to a main flow (FIG. 9) described later and a RAM part for loading and storing a sound source processing program described later from the external memory 116 of FIG. The memory address control unit 20
5, the program word (command) of the designated address is sequentially output via the program address decoder 202. Specifically, the word length of each program word is, for example, 28 bits, and a part of the program word is input to the memory address control unit 205 as a lower part (in-page address) of the address to be read next. It is a method.

When the tone color or the like is changed and the tone generator system executed for each tone generation channel is changed, the corresponding tone generator processing programs are collectively loaded from the external memory 116 of FIG. 1 to the program memory 201. This point is a feature of this embodiment.

The command analysis unit 207 has a control RAM 2
The operation code of the instruction output from 01 is analyzed, and a control signal is sent to each part of the circuit to execute the specified operation.

The RAM address control unit 204 controls the control R
When the operand of the instruction from the AM 201 specifies a register, the address of the corresponding register in the RAM 206 is specified. The RAM 206 has a configuration shown in FIGS.
Various tone control data, which will be described later, are stored for eight sounding channels, and various buffers, which will be described later with reference to FIG.

When the instruction from the control RAM 201 is an operation instruction, the ALU unit 208 and the multiplier 209 execute addition / subtraction and logical operation, and the latter execute multiplication, based on the instruction from the command analysis unit 207.

The interrupt control unit 203, based on an internal hard timer (not shown), at regular time intervals,
1, the reset release signal A, the memory address control unit 205, and each D / A converter unit 107 of FIG.
An interrupt signal is supplied to 108.

In addition to the above configuration, the MCPU 101 shown in FIG.
Is provided with interfaces related to the following various buses. That is, in order to access the external memory 116, the interface 215 of the address bus MA for designating the address of the memory, and the data for exchanging the accessed data with the MCPU 101 via the external memory selector unit 106. The bus MD interface 216 and the SCPU 102 are used to exchange data with the SCPU 102.
A bus Ma for designating the address of the RAM inside the CPU 102
Interface 212, MCPU 101 is SCPU 102
An interface 213 of a data bus Dout for writing data into the SCU 102 and an interface 21 of a data bus Din for the MCPU 101 to read data from the SCPU 102.
4, a D / A data transfer bus interface 217 for transferring the final output waveform to the Left D / A converter unit 107 and the Right D / A converter unit 108, and an external switch unit or keyboard unit (FIG. 7, (See FIG. 8) and the like, there are input / output ports 210 and 211 for transmitting and receiving data.

Next, the internal structure of the SCPU 102 is shown in FIG. Since the SCPU 102 only receives a processing start signal from the MCPU 101 and performs sound source processing, it exchanges data with an interrupt control unit corresponding to 223 in FIG. 2 and an external circuit corresponding to 210 and 211 in FIG. Left D / A converter unit 10 corresponding to the input / output port and 217 of FIG.
7 and Right D / A converter section 108 does not have an interface for outputting a tone signal. Other 301, 30
2, 304 to 309 correspond to the circuits 201 and 20 in FIG.
It has the same function as each of the circuits 2, 204 to 209. In addition, each interface 303, 310 to 313 is shown in FIG.
Nos. 212 to 216 are provided so as to face each other. The SCP specified by the MCPU 101 via the bus Ma
The U 102 internal RAM address is input to the RAM address control unit 304, and the corresponding address is designated to the RAM 306. As a result, for example, the accumulated waveform data for a maximum of eight sound generation channels generated in the SCPU 102 and held in the RAM 306 is output to the MCPU 101 via the data bus Din. This will be described later.

When changing the timbre, the corresponding sound source processing programs are collectively sent from the external memory 116 shown in FIG. 1 to the MCPU 101, as in the case of the MCPU 101 described above.
Loaded via. This transfer operation is performed by the MCPU 1 of FIG.
The command analysis unit 207 and the memory address control unit 205 in 01 are executed by controlling the program RAM 301 and the RAM address control unit 305 via the gate circuit 314.

In addition to the configuration shown above, in this embodiment, the input port 210 of the MCPU 101 is connected to the input port 210 of FIG.
A function key 701, a keyboard key 702, etc. as shown in FIG. These parts constitute a substantial musical instrument operation unit.

Next, FIG. 5 shows D / of Left and Right in FIG.
The internal configuration of the A converters 107 and 108 (the contents of both converters are the same) is shown. One sample data of a musical sound created by sound source processing is input to the latch 401 via a data bus. The clock input to the latch 401 is M
When the tone generator processing end signal is input from the command analysis unit 207 (FIG. 2) of the CPU 101, one sample of musical tone data on the data bus is latched by the latch 401.

Here, the time required for the above sound source processing is
Varies depending on the sound source processing software. for that reason,
When the sound source systems are different, the timings at which the tone data is latched in the latch 401 are not constant because each sound source processing is completed. Therefore, as shown in FIG. 4, the output of the latch 401 cannot be directly input to the D / A converter 402.

Therefore, in the present embodiment, as shown in FIG. 5, the output of the latch 401 is further latched by the latch 501, and the interrupt signal shown in FIG.
The musical tone signal is latched by the latch 501 and output to the D / A converter 402 at regular intervals as shown in FIG.

As described above, since two latches are used to absorb the change in the processing time due to the sound source method, the musical tone data is D
A complicated timing control program for outputting to the A / A converter is no longer needed. <Overall Operation of this Embodiment> Next, the overall operation of this embodiment will be described.

In this embodiment, the MCPU 101 is basically the center of operation, and as shown in the main flow chart of FIG. 9, a series of processing of S902 to S910 is repeated. The actual sound source processing is performed by interrupt processing. Specifically, the MCPU 101 and the SCPU 102 are interrupted at regular intervals,
Based on this, each CPU performs sound source processing for producing sounds of up to 8 channels.

Here, as will be described later, different tone generator systems such as PCM, DPCM, FM or TM can be assigned to each tone generation channel, and a tone generator processing program for 8 channels corresponding to the assignment. Are collectively set from the external memory 116 (FIG. 1) to the program memory 201 (FIG. 2) or the program RAM 301 when setting a tone color.
It is a feature of the present embodiment that it is loaded into.
As a result, it is not necessary to perform a discrimination process of which sound source method is used to generate a musical tone for each sounding channel. The transfer operation will be described later.

When the sound source processing by the interrupt processing is completed, musical tone waveforms of up to 8 channels of each CPU, up to 16 channels in total, are added, and the left D / A converter unit 107 and the Right D / A converter unit 108 Is output.
Thereafter, the process returns from the interrupt state to the main flow. In addition,
The above-mentioned interrupt is periodically performed based on the hard timer in the interrupt control unit 203 of FIG. This cycle is equal to the sampling cycle when outputting a musical sound.

The above is the general overall operation of this embodiment. Next, regarding the details of the entire operation of the present embodiment, FIG.
This will be described with reference to FIG. If an interrupt is issued from the interrupt control unit 203 while the processes of S902 to S910 of the main flowchart of FIG. 9 are repeatedly executed, the MCPU interrupt process of FIG. 10 and the SCPU of FIG.
Two processes of the interrupt process are activated at the same time. Then, the “sound source processing” of FIGS. 10 and 11 will be described later with reference to FIG.
Is shown in

The main flow chart of FIG. 9 shows the flow of processing other than the sound source processing, which is executed in the MCPU 101 in a state where the interrupt is not interrupted by the interrupt control unit 203.

First, when the power is turned on, the MCPU 101
The initial settings of the contents of the RAM 206 are performed (S901).
). Next, the function key 701 (see FIG. 7) connected to the outside of the MCPU 101, for example, a tone color switch or the like is scanned (S902), and the state of each switch is fetched from the input port 210 into the key buffer area in the RAM 206.
As a result of the scanning, the function key whose state has changed is identified,
The corresponding function is processed (S903). For example, setting of a musical tone number, setting of an envelope number, and setting of a rhythm number if the additional function has rhythm performance.

After that, the state of the depressed keyboard key is taken in as in the case of the above-mentioned function key (S904),
The key assignment process is performed by identifying the changed key (key depressed or key released) (S905). This process is a process of assigning data of a musical tone to be generated based on a depressed key to a sound generation channel, and conversely releasing a sound generation channel corresponding to a released key. Note that the key-on assignment process, which is part of the process executed here, is only the process of assigning a key-depressed key to a tone generation channel, and the pitch data based on the key-depressed key is actually set in the assigned tone generation channel The operation of giving a sounding instruction is executed in a sounding process (S909) described later.

Next, when the demo performance key, which is the function key 701 (see FIG. 7), is pressed, the demo performance data (sequencer data) is sequentially read from the external memory section 116, and key assignment similar to S905 is performed. Processing and the like are performed (S906). When the rhythm start key is pressed, the rhythm data is sequentially read from the external memory 116 and the key assignment processing similar to S905 is performed (S907).

After that, the following timer processing is performed (S908). That is, the time value of the time data incremented in the interrupt timer process (S1012) described later is determined, and the sequencer data for time control sequentially read for demo performance control or the time control read for rhythm performance control is read. By comparing with the rhythm data, the time control for performing the demo performance of S906 or the rhythm performance of S907 is performed.

Further, in the tone generation processing S909, pitch data is set in the tone generation channel which is assigned in each of the above steps S905 to S907 and the tone generation is to be started, and the pitch data of the tone generation channel being sounded is set in accordance with a preset envelope. Pitch envelope processing or the like is performed in which the pitch is changed over time to add a change to the pitch of the musical tone being sounded.

Further, a flow one round preparation process is executed (S910). Here, processing such as changing the state of the sounding channel for which the pitch data is newly set in the above-described step S909 to sounding, or conversely changing the state of the sounding channel released in steps S905 to S907 to mute Done.

Next, the MCPU interrupt processing of FIG. 10 will be described. Interrupt control unit 20 of MCPU 101
When the MCPU 101 is interrupted by 3, the process of the main flowchart of FIG. 9 is interrupted, and the MCPU 101 of FIG.
The execution of the interrupt process is started. In this case, MCP
In the U interrupt processing program, the registers and the like written in the main flow program of FIG. 9 are controlled so that the contents are not rewritten. This eliminates the need to save and restore the registers at the start and end of the normal interrupt processing, and the transition between the processing of the main flowchart of FIG. 9 and the MCPU interrupt processing can be performed quickly.

In FIG. 10, first, sound source processing is started in the MCPU interrupt processing (S1011). This sound source processing is shown in FIG. 13 described later. Simultaneously with the above operation, the interrupt control unit 203 of the MCPU 101 sends an S to the RAM address control unit 305 of the SCPU 102.
CPU reset release signal A (see Fig. 1) is output and SCP
In U 102, execution of the SCPU interrupt process of FIG. 11 is started.

Then, almost simultaneously with the sound source processing in the MCPU interrupt processing (S1011), the sound source processing in the SCPU interrupt processing is started (S1101). As described above, both the MCPU 101 and the SCPU 102 execute the sound source processing in parallel, so that the processing speed of the sound source processing is approximately doubled as compared with the case of executing the sound source processing by one CPU.

Subsequently, the MCPU 101 waits for an end signal of the SCPU interrupt processing from the SCPU 102 after the interrupt timer processing of S1012 (S10).
13). Note that in the interrupt timer process, the value of time data (not shown) on the RAM 206 (FIG. 2) is incremented by utilizing the fact that the interrupt process of FIG. 10 is executed at regular sampling intervals. That is, the value of the time data indicates the passage of time. As described above, the time data thus obtained is used for the time control in the timer processing S908 of the main flow of FIG.

When the sound source processing of step S1101 in the SCPU interrupt processing of FIG. 11 is completed, the SCPU 102
The SCPU processing end signal B (see FIG. 1) is input to the memory address control unit 205 of the MCPU 101 from the command analysis unit 307 of FIG. As a result, the determination at step S1013 in the MCPU interrupt processing of FIG. 10 becomes YES.

As a result, the waveform data created by the SCPU 102 via the data bus Din of FIG.
It is read into the AM 206 (S1014). In this case, since the waveform data is stored in the predetermined buffer area (buffer B described later in FIG. 17) on the RAM 306 of the SCPU 102, the command analysis unit 207 of the MCPU 101 uses the SCP
U The waveform data is read by designating the buffer address to the RAM address control unit 304 via the internal address designating bus Ma.

Then, in S1014 ', the contents of the buffer area are changed to the Left D / A converter section 107 and the Right D / A converter section 107.
It is latched by the latch 401 (see FIG. 5) of the A / A converter unit 108.

Next, FIG. 12 is a flow chart conceptually showing the relationship between the processes of the flowcharts of FIGS. 9 and 10 and showing how the MCPU 101 and SCPU 102 share the sound source processing. Shows.

First, a process A (hereinafter, processes B, C, ...
.. and F are the same) are executed (S1201). This processing corresponds to, for example, "function key processing" or "keyboard key processing" in the main flowchart of FIG. Then M
The CPU interrupt processing and the SCPU interrupt processing are entered, and at the same time, the sound source processing by the MCPU 101 and SCPU 102 is started (S1202, S1203). And SCPU 10
At the end of the SCPU interrupt processing in 2, the SCPU processing end signal B is input to the MCPU 101. In the MCPU interrupt process, the sound source process is completed earlier than the SCPU interrupt process, and the completion of the SCPU interrupt process is awaited. When the SCPU processing end signal B is identified in the MCPU interrupt processing, the waveform data generated by the SCPU 102 is sent to the MCPU 101 and combined with the waveform data generated by the MCPU 101, and the Left D / A converter It is output to the unit 107 and the Right D / A converter unit 108. After that, the process returns to the process B following the process A in the main flowchart.

The above operation is repeated while sound source processing is being performed for all tone generation channels (tone generation channels being executed by the MCPU 101 and SCPU 102) (S
1204-S1216). This repetition processing is continued while the musical sound is being generated.

FIG. 13 shows step S1011 of the MCPU interrupt process or step S11 of the SCPU interrupt process.
It is an operation | movement flowchart of the sound source process performed by 01.
First, the area of the RAM 206 or RAM 306 for waveform data addition is cleared (S1316). Next, sound source processing is performed for each sound generation channel (S1317 to S132).
4) Finally, when the sound source processing for the eighth channel is completed, waveform data obtained by adding eight channels to a predetermined buffer area B (FIG. 17 described later) on the RAM 206 is obtained. <Data Structure in Sound Source Processing> Next, S1011 in FIG.
A specific example of the sound source processing executed in S1101 of FIG. 11 will be described.

In this embodiment, the MCPU 101 and the SCPU 10
It has been described above that the two CPUs 2 share the sound source processing for each of the maximum 8 channels. As shown in FIG. 14, the data for sound source processing for up to 8 channels is MCPU 101, S
It is set in the area for each sound generation channel in the RAM 206, 306 of the CPU 102.

Further, in the RAM, as shown in FIG. 17, a buffer B common to all tone generation channels is secured. In this case, each sound source system can be set in each sound generation channel region of FIG. 14 by an operation as described in detail later, as conceptually shown in FIG. Data is set in each area of each sound generation channel of FIG. 14 in the data format of each sound source method as shown in FIG. In this embodiment, as will be described later, it is possible to assign a different sound source system to each sounding channel.

In Table 1 showing the data format of each sound source system of FIGS. 15 and 16, A represents an address designated when waveform data is read during sound source processing, and AI, A1 and A2 are current addresses. The integer part directly corresponds to the address where the waveform data of the external memory 116 (FIG. 1) is stored. AF is a fractional part of the current address and is used for interpolation of the waveform data read from the external memory 116.

Next, AE represents an end address and AL represents a loop address. The following PI, P1 and P2 represent the integer part of the pitch data, and PF represents the fractional part of the pitch data. For example, PI = 1 and PF = 0 are pitches of the original sound, PI = 2 and PF = 0 are pitches one octave higher, and PI = 0 and PF = 0.5 are pitches one octave lower. Represents each pitch.

The next XP is the same as the previous sample data, XN
Indicates the storage of the next sample data (described later). Further, D represents the difference value of the size between two adjacent sample data, and E is the envelope value. Furthermore, O is an output value.

Various other control data will be described in the description of each sound source method described later. The data as shown in FIGS. 15 and 16 as described above is the MCPU 10
1. When the sound source system, which will be described later, is secured in the RAMs 206 and 306 of the SCPU 102, data is set in the format of FIGS. 15 and 16 for each channel shown in FIG.

The sound source processing of each sound source method executed using such a data structure will be sequentially described below. Here, according to the setting of the tone color, etc.
Different sound source schemes such as M, DPCM, FM or TM can be assigned. Then, when the tone color or the like is set, the sound source processing programs in which the sound source schemes for 8 channels are determined are collectively processed from the external memory 116 (FIG. 1) to the program memory 201 (FIG. 2) or the program RAM 30.
Loaded to 1. As a result, for each pronunciation channel,
A sound source processing program whose sound source method has been determined is automatically executed. The principle of each sound source method executed as these sound source processing programs will be described below.
The transfer operation of the sound source processing program will be described later. <Sound Source Processing by PCM Method> FIG. 18 is an operation flowchart when the sound source processing by the PCM method is executed. Each variable in the flow is MCPU 101 or SCPU 1
14 is each data in the PCM format of the table 1 of FIGS. 15 and 16 stored in one of the tone generation channel areas of FIG.

Of the addresses where the PCM waveform data is stored in the external memory 116 (FIG. 1), the addresses where the waveform data to be currently processed are stored are shown in FIG. 21 (AI, AF). And

First, the pitch data (P
I, PF) are added (S1901). This pitch data corresponds to the type of key pressed by the keyboard key 702 or the like in FIG.

Then, the integer part AI of the added address
It is determined whether or not has changed (S1902). Judgment is NO
Then, using the difference value D which is the difference between the sample data XN and XP at the addresses (AI + 1) and AI in FIG. 21, the interpolation processing corresponding to the fractional part AF of the address is performed by the arithmetic processing of D × AF. The data value O is calculated (S1907). The difference value D is obtained by the sound source processing at the interrupt timing before this time (see S1906 described later).

Then, the sample data XP corresponding to the integer part AI of the address is added to the interpolation data value O,
New sample data O (corresponding to XQ in FIG. 21) corresponding to the current address (AI, AF) is obtained (S19).
08).

After this, this sample data is multiplied by the envelope value E (S1909), and the contents of the obtained O are MCP.
It is added to the waveform data buffer B (see FIG. 17) in the RAM 206 or 306 of the U 101 or SCPU 102 (S1910).

After that, returning to the main flow of FIG. 9, an interrupt is applied at the next sampling period, the operation flowchart of the sound source processing of FIG. 18 is executed again, and the pitch data (PI, PF) is added to the current address (AI, AF). ) Is added (S1901).

The above operation is repeated until the integer part AI of the address changes (S1902). During this time, the sample data XP and the difference value D are not updated, only the interpolation data O is updated according to the address AF, and the sample data XQ is obtained each time.

Next, in S1901, the current address (AI, AF)
If the integer part AI of the current address changes as a result of adding the pitch data (PI, PF) to (S1902), it is determined whether the address AI has reached or exceeded the end address AE (S1903). .

If the determination is YES, the following loop processing is performed. That is, the address beyond the end address AE (AI-AE) is added to the loop address AL, and the integer part A of the new current address obtained thereby is added.
Loop reproduction is started from I (S1904). The end address AE is an address on the external memory 116 (FIG. 1) in which the last waveform sample data of the PCM waveform data is stored. The loop address AL is the address of the position where the performer wants the waveform output to repeat,
By the above operation, a well-known loop process is realized by the PCM method.

If the determination in S1903 is NO, the process in step S1904 is not executed. Next, the sample data is updated. Here, the sample data corresponding to the newly updated current address AI and the immediately preceding address (AI -1) are read from the external memory 116 (see FIG. 1) as XN and XP, respectively (S190).
Five).

Further, the difference value up to now is the updated X
The difference value D between N and XP is updated (S1906). The operation thereafter is as described above.

As described above, P for one sound channel
Waveform data based on the CM method is generated. <Sound Source Processing by DPCM System> Next, the DPCM system will be described.

First, the operating principle of the DPCM system will be outlined with reference to FIG. In the figure, the external memory 1
The sample data XP corresponding to the address AI of 16 (FIG. 1) is a value obtained from the difference value from the sample data corresponding to the address (AI -1) not shown, which is immediately before the address AI.

Address AI of external memory 116 (FIG. 1)
Since the next difference value D is written in, the sample data at the next address is found by XP + D, and this is replaced as new sample data XP. In this case, if the current address is AF as shown in FIG. 22, the sample data corresponding to the current address AF is XP + D × AF
Is determined by

As described above, in the DPCM method, the difference value D between the current address and the sample data corresponding to the next address is read from the external memory 116 (FIG. 1),
The waveform data is sequentially created by adding the current sample data and obtaining the next sample data.

When such a DPCM method is adopted, when quantizing a waveform such as a voice or a musical sound whose difference value between adjacent samples is generally small, the number of bits is much smaller than that of the normal PCM method. You can quantize with.

FIG. 19 and FIG. 20 show operation flowcharts when the sound source processing by the above DPCM method is executed. Each variable in the flow is the RAM 206 of the MCPU 101.
Alternatively, it is each data in the DPCM format of the table 1 of FIG. 15 stored in one of the tone generation channel areas of FIG. 14 on the RAM 306 of the SCPU 102.

Of the addresses where the DPCM difference waveform data is stored on the external memory 116 (FIG. 1), the addresses where the data to be currently processed are stored are shown in FIG. 22 (AI, AF). ).

First, the pitch data (PI, PF) is added to the current address (AI, AF) (S2001). Then, it is determined whether or not the integer part AI of the added address has changed (S2002). If the judgment is NO, the interpolated data value O corresponding to the fractional part AF of the address is calculated by the calculation process of D × AF using the difference value D at the address AI of FIG. 22 (S2014). The difference value D
Is obtained by the sound source processing at the interrupt timing before this time (see S2006 and S2010 described later).

Next, the sample data XP corresponding to the integer part AI of the address is added to the interpolation data value O, and new sample data O (corresponding to XQ in FIG. 22) corresponding to the current address (AI, AF) is obtained. Obtained (S2015).

Thereafter, this sample data is multiplied by the envelope value E (S2016), and the content of the obtained O is MCP.
RAM 206 of U 101 or RAM 30 of SCPU 102
It is added to the waveform data buffer B in 6 (see FIG. 17) (S2017).

Then, returning to the main flow of FIG. 9, an interrupt is applied in the next sampling cycle, and the operation flowcharts of the sound source processing of FIGS. 19 and 20 are executed again.
Pitch data (PI, PF) at the current address (AI, AF)
Is added (S2001).

The above operation is repeated until a change occurs in the integer part AI of the address. During this time, the sample data XP and the difference value D are not updated, only the interpolation data O is updated according to the address AF, and new sample data XQ is obtained each time.

Next, in S2001, the current address (AI, AF)
If the integer part AI of the current address changes as a result of adding the pitch data (PI, PF) to (S2002), it is determined whether the address AI reaches or exceeds the end address AE (S2003). .

When the determination is NO, the following S2004-S2007
By the loop processing of, the sample data corresponding to the integer part AI of the current address is calculated. That is, first, the value before the change of the integer part AI of the current address is stored in the variable called the old AI (see the column of DPCM in Table 1 of FIG. 15). The storage of this value is realized by repeating the processing of S2006 or S2013 described later. This old A
While the value of I is sequentially incremented in S2006, S20
External memory 116 designated by old AI at 07 (Fig. 1)
The difference waveform data above is read out as D and is sequentially accumulated in S2005 as sample data XP. Then, when the value of the old AI becomes equal to the integer part AI of the changed current address, the value of the sample data XP becomes the value corresponding to the integer part AI of the changed current address.

In this way, the integer part A of the current address
When the sample data XP corresponding to I is obtained, the determination in S2004 is YES, and the above-described interpolation value calculation processing (S201
Go to 4).

The above-described sound source processing is repeated at each interrupt timing, and when the determination in S2003 changes to YES, the next loop processing is started. First, the end address AE
The address (AI-AE) that exceeds this is added to the loop address AL, and the obtained address is set as the integer part AI of the new current address (S2008).

Thereafter, the operation of accumulating the difference value D is repeated several times depending on how much the address has advanced from the loop address AL, so that the sample data XP corresponding to the integer part AI of the new current address is calculated. To be done. That is, first, as an initial setting, the sample data X
P is the value of the sample data XPL (see the DPCM column in Table 1 of FIG. 15) at the preset loop address AL, and the old AI is the loop address AL.
(S2009). And the following S2010-S20
The process of 13 is repeated. That is, the old AI value is S20.
The differential waveform data on the external memory 116 (FIG. 1) instructed by the old AI is read out as D in S2010 while being sequentially incremented in 13, and is sequentially accumulated in S2012 in the sample data XP. Then, when the value of the old AI becomes equal to the integer part AI of the new current address,
The value of the sample data XP becomes the value corresponding to the integer part AI of the new current address after the loop processing.

In this way, when the sample data XP corresponding to the new integer part AI of the current address is obtained, S
When the determination in 2011 is YES, the process proceeds to the above-described interpolation value calculation process (S2014).

As described above, D for one sound generation channel
Waveform data based on the PCM method is generated. <Sound Source Processing by FM Modulation Method> Next, sound source processing by the FM modulation method will be described.

In the FM modulation method, normally, OP1 and OP in FIG.
A hardware or software module having the same function called an operator as shown in Fig. 2 is used, and these are connected to each other according to the connection rule shown in the figure to generate a musical tone. Be seen. In this embodiment, the FM modulation method is realized by software processing.

FIG. 23 is an operation flow chart when the sound source processing by the FM modulation method of two operators is executed. The processing algorithm is shown in FIG. Also,
Each variable in the flow is each data in the FM format of the table 1 of FIG. 16 stored in the tone generation channel area of one of the RAMs 206 and 306 of the MCPU 101 or SCPU 102 of FIG.

First, operator 2 which is a modulator
(OP2) processing is performed. PC for pitch processing
Since the interpolation is not performed unlike the M method, the integer address A
Only two. That is, it is assumed that the waveform data for modulation is stored in the external memory 116 (FIG. 1) at sufficiently fine step intervals.

First, the pitch data P is assigned to the current address A2.
2 is added (S2401). Next, the feedback output F02 is added to this address A2 as a modulation input to obtain a new address AM2 (S2402). The feedback output F02 is obtained by executing the process of S2405 described below at the previous interrupt timing.

Further, the value of the sine wave corresponding to the address AM2 (phase) is calculated. In practice, the external memory 116
The sine wave data is stored in (FIG. 1) and is obtained by drawing a table of the sine wave data at the address AM2 (S2403).

Then, the sine wave data is multiplied by the envelope value E2 to obtain the output O2 (S2404). Thereafter, this output O2 is multiplied by the feedback level FL2 to obtain the feedback output F02 (S2405). In the case of this embodiment, this output F02 is input to the operator 2 (OP2) at the next interrupt timing.

Also, the modulation level M for O2
It is multiplied by L2 to obtain the modulation output MO2 (S2406). This modulation output M02 becomes a modulation input to the operator 1 (OP1).

Next, the processing of the operator 1 (OP1) is started.
This process is almost the same as the case of the operator 2 described above except that there is no modulation input by the feedback output. First, the pitch data P is added to the current address A1 of the operator 1.
1 is added (S2407), and the above-mentioned modulation output MO2 is added to this value to obtain a new address AM1 (S2408).

Next, the value of the sine wave corresponding to this address AM1 (phase) is read from the external memory 116 (FIG. 1) (S2409), and this is multiplied by the envelope value E1 to obtain the tone waveform output O1. (S2410).

Then, this is added to the buffer B (see FIG. 17) in the RAM 206 (FIG. 2) or 306 (FIG. 3) (S2411), and the FM modulation processing for one sound channel is completed. <Sound Source Processing by TM Modulation Method> Next, sound source processing by the TM modulation method will be described.

First, the principle of the TM modulation method will be described. The FM modulation method described above is based on the arithmetic expression e = A · sin {ωct + I (t) · sinωmt}. Where ωct is the carrier wave phase angle (carrier signal), sin ωmt is the modulated wave phase angle (modulated signal),
And I (t) are the modulation indices.

On the other hand, the phase modulation method called the TM modulation method in this embodiment is basically based on the arithmetic expression of e = Af _T {fc (t) + I (t) sinωmt}. Here, f _T (t) is a triangular wave function and is defined by the following function for each phase angle region (where ω is an input).

F _T (ω) = 2 / πω (region: 0 ≦ ω ≦ π / 2) f _T (ω) = − 1 + 2 / π (3π / 2−ω) (region : π / 2 ≤ ω ≤ 3π / 2) f _T (ω) = -1 + 2 / π (ω-3 π / 2) ・ ・ ・ (Area: 3π / 2 ≤ ω ≤ 2π) Also, fc is the modified sine wave. Is a carrier signal generation function obtained by accessing the external memory 116 (FIG. 1) in which different sine waveform data is stored for each phase angle region at the carrier phase angle ωct. For each phase angle region
fc is defined as follows.

Fc (t) = (π / 2) sin ωct (area: 0 ≦ ωct ≦ π / 2) fc (t) = π− (π / 2) sin ωct (area: π ≦ ωct ≦ 3π / 2) fc (t) = 2π + (π / 2) sin ωct (area: 3π / 2 ≦ ωct ≦ 2π) In the TM modulation method, a carrier signal generated by the function fc (t) as described above. In addition, the above-mentioned triangular wave function is modulated by the addition signal obtained by adding the modulation signal sin ωmt at the ratio indicated by the modulation index I (t). With this, if the value of the modulation index I (t) is 0, a sine wave can be generated, and if the value of I (t) is increased, a very deeply modulated waveform can be generated. . Here, various signals can be used in place of the modulation signal sin ωmt, and as described below, the operator's output during the previous calculation is fed back at a constant feedback level, or the output of another operator is input. It can be done.

FIG. 25 shows an operation flowchart in the case where the sound source processing by the TM modulation method is executed based on such a principle. Also in this case, as in the case of the FM modulation method in FIG. 23, this is an example of the case where the sound source processing is performed by two operators, and the processing algorithm is shown in FIG. In addition, each variable in the flow is the R of the MCPU 101 or SCPU 102.
It is each data of the TM format of the table 1 of FIG. 16 stored in one of the tone generation channel areas of FIG. 14 on the AMs 206 and 306.

First, operator 2 which is a modulator
(OP2) processing is performed. PC for pitch processing
Since the interpolation is not performed unlike the M method, the integer address A
Only two.

First, the pitch data P is assigned to the current address A2.
2 is added (S2601). Next, by the modified sine conversion fc, the modified sine wave corresponding to the address A2 (phase) is read from the external memory 116 (FIG. 1), and the carrier signal is generated as O2 (S2602).

Then, the feedback output FO2 (S2606) is added as a modulation signal to the above-mentioned O2 which is a carrier signal, and a new address is obtained to be O2 (S260).
3). The feedback output F02 is obtained by executing the process of S2606 described later at the previous interrupt timing.

Then, the value of the triangular wave corresponding to the above-mentioned addition address O2 is calculated. In reality, the external memory 11
6 (FIG. 1) stores the above-mentioned triangular wave data,
It is obtained by drawing a table of the triangular wave data at the address O2 (S2604).

Subsequently, the triangular wave data is multiplied by the envelope value E2 to obtain the output O2 (S2605). Thereafter, this output O2 is multiplied by the feedback level FL2 to obtain the feedback output F02 (S2607). In the case of this embodiment, this output F02 is input to the operator 2 (OP2) at the next interrupt timing.

Also, the modulation level M for O2
L2 is multiplied to obtain the modulation output MO2 (S2607). This modulation output M02 becomes a modulation input to the operator 1 (OP1).

Next, the processing of the operator 1 (OP1) is started.
This process is almost the same as the case of the operator 2 described above except that there is no modulation input by the feedback output. First, the pitch data P is added to the current address A1 of the operator 1.
1 is added (S2608), the above-mentioned modified sine transform is performed on the obtained value, and the carrier signal is obtained as O1 (S2609).

Next, the above-mentioned modulation output MO2 is added to this O1 to obtain a new O1 (S2610), this value O1 is subjected to triangular wave conversion (S2611), and the envelope value E1 is further multiplied to obtain the tone waveform output O1. Is obtained (S
2612).

This is the RAM 206 (FIG. 2) or 306.
It is added to the buffer B (see FIG. 17) in (FIG. 3) (S
2613) The TM modulation processing for one sound channel is completed.
Up to this point, the operation principle has been described in the case where the four various sound source systems of PCM, DPCM, FM and TM are executed. Of these, the two systems, FM and TM, are modulation systems, and in the above example, both are processes by two operators based on the algorithms shown in FIGS. 24 and 26. May be more complex and the algorithm may be more complex. <Transfer Operation of Sound Source Processing Program> Finally, the transfer operation of the sound source processing program related to the present invention will be described.

As described above, depending on the setting of the tone color or the like,
Different sound source systems such as PCM, DPCM, FM or TM can be assigned to each sounding channel. And
When a tone color or the like is set, a sound source processing program in which a sound source method for eight channels is determined is collectively loaded from the external memory 116 (FIG. 1) to the program memory 201 (FIG. 2) or the program RAM 301. As a result, it is not necessary to perform the determination process of which sound source method is used to generate a musical sound for each sounding channel.

In this case, the program memory 201 of the MCPU 101 is composed of a ROM portion and a RAM portion, and the ROM portion prestores the program of the main flow of FIG. On the other hand, in the RAM part,
At the time of setting a tone color, the interrupt processing program of FIG. 10 is collectively transferred from the external memory 116 of FIG. Further, the interrupt processing program of FIG. 11 is similarly transferred to the program RAM 301 of the SCPU 102.

FIG. 27 shows the data arrangement of various sound source processing programs stored in advance in the external memory 116, and FIG. 28 shows the RAM arrangement of the program memory 201 in the MCPU 101 or the program RAM 301 in the SCPU 102. Show.

Now, when the performer sets a tone color or the like by using the function key 701 of FIG. 7, the musical tone waveform generating apparatus according to the present embodiment produces, for example, eight tones for generating musical tones on the MCPU 101 and SCPU 102. In each of the channels, for example, musical tone generation is performed by the PCM method in all sound generation channels, or musical tone generation is performed by the TM method, or 1 to 3
Musical tones can be generated by the FM system for channels, the TM system for 4 to 6 channels, and the PCM system for 7 to 8 channels.

Then, on the external memory 116, for example, a sound source processing program for eight continuous channels based on the operation flow chart of FIG. 13 for generating musical tones by the PCM system for all tone generation channels, or musical tone generation by the TM system. 8 channel continuous sound source processing program for performing, or FM channel for 1 to 3 channels, TM method for 4 to 6 channels, and 8 channel continuous tone generation for PCM method on 7 to 8 channels. The sound source processing program is stored in an independent address area on the external memory 116 as shown in FIG.

The data arrangement in this case is in units of 16 bits as shown in FIG. This is the external memory 11
This is because when a general-purpose ROM or the like is used as 6, etc., there are many 16-bit units, so that it is possible to deal with it. The sound source processing program described above is stored in each address area allocated in units of 16 bits.

On the other hand, the data arrangement of the RAM portion of the program memory 201 and the program RAM 301 is 28-bit next-address type program data as shown in FIG.

Then, on the program memory 201,
For example, addresses 1BFF to 1F allocated in 28-bit units
The above-mentioned sound source processing program for eight continuous channels is transferred from the external memory 116 to FF (hexadecimal notation).
The address portion before the address 1BFF is an RO for storing the program corresponding to the main flow of FIG.
It is the M region.

Here, at the time of transferring the program data of the sound source processing from the external memory 116 to the program memory 201, the command analysis unit 207 and the memory address control unit 205 of FIG. 2 which will be described later synchronize their addresses.

The above operation is similarly performed for the program RAM 301. However, the program RAM 30
Since No. 1 only performs sound source processing, there is no ROM area for storing the main flow of FIG.

Next, the specific transfer operation of the sound source processing program based on the above data arrangement will be described with reference to the operation timing chart of FIG. This transfer operation is
The command analysis unit 207 in the MCPU 101 shown in FIG.
2 of (b) and (c) in the figure generated from the original oscillation clock in (a)
It shall be executed in synchronization with the phase clocks CK2 and CK1.

First, when the performer performs a tone color setting operation using the function key 701 shown in FIG. 7, the command analysis section 207 causes the command analysis section 207 shown in FIG.
29 (i) in the function key processing of step S903 in FIG.
The execution of the sound source processing program transfer instruction is started at the timing of. The following operations are all realized as an operation in which the command analysis unit 207 executes the transfer instruction.

First, the command analysis unit 207 determines the sound source processing group corresponding to the set tone color, and determines the start address on the external memory 116 in which the continuous sound source processing programs for 8 channels corresponding thereto are stored. decide.

Then, the command analysis section 207 sends an address signal sequentially incremented as shown in FIG. 29 (d) from the above start address via the external memory access address bus interface 215, the address bus MA, etc. of FIG. And supplies it to the external memory 116. by this,
Addresses in which continuous sound source processing programs for 8 channels corresponding to the set tone color, which are allocated in 16-bit units in FIG. 27, are sequentially designated, and consist of continuous 16-bit and 12-bit valid data. The program data PRG is a, a ', b, b', ...
.. are sequentially output.

Both the 16-bit valid data and the 12-bit valid data are input from the 16-bit data bus MD of FIG. 1 to the external memory data bus interface 216 of the MCPU 101 of FIG. 201 is transferred.

At the same time, the command analysis unit 207 sends the address switching signal C rising to a high level as shown in FIG. 29 (h) to the memory address control unit 205 of the MCPU 101 of FIG. 2 and the RAM of the SCPU 102 of FIG. It is output to the address control unit 305 and the gate circuit 314. When the address switching signal C is at the high level, the memory address control unit 205 does not generate the program address for tone generation, and is sequentially incremented A0 as shown in FIG. 29 (e).
An address signal ADR consisting of 13 bits from A12 to A12 is output. The address signal ADR is input to the program address decoder 202.

Further, since the address switching signal C is at the high level, the gate circuit 314 in FIG. 3 selects the program data PRG for tone generator processing transferred from the external memory 116 via the MCPU 101 in FIG. The address signal ADR is selected and sent to the RAM address control unit 305. Then, the control unit 305 stores it as it is in the RAM.
Input to the address decoder 302. As a result, FIG.
Addresses 1BFF to 1FFF allocated in 28-bit units of 8
Are sequentially specified.

At the same time, the command analysis section 207 has the function shown in FIG.
An up / down instruction signal UD as shown in FIG. 29H and a write signal to W as shown in FIG.
Supply to M301.

By the above control operation, the external memory 11
2 of continuous 16-bit and 12-bit data of the sound source processing program data PRG output from
The lower 16 bits and the upper 12 bits (determined by the up / down instruction signal UD) of each address (determined by the 13-bit address signal ADR) on the program memory 201 and the program RAM 301 are sequentially stored.

As described above, the memory address control unit 205 controls the program address decoder 202 and the RAM.
When the 13-bit address signal ADR designated to the address decoder 302 is incremented to 1FFF as shown in FIG. 29 (e) and the transfer of the program data PRG of the continuous sound source processing for 8 channels is completed, this is notified. The control unit 205 notifies the command analysis unit 207. As a result, the analysis unit 207 ends the generation of the address signal for the external memory 116 as shown in FIG. 29 (d), and at the same time, as shown in FIG. 29 (f), (g), (h), the up / down instruction signal. The UD, the write signal to W, and the address switching signal C are returned to the low level.

The above-described processing operation is performed by the command analysis unit 207.
However, in the function key processing of step S903 of FIG.
This is realized by executing the sound source processing program transfer instruction of 9 (i). During the above-described processing operation, the command analysis unit 207 of FIG. 2 controls the interface control unit 203 so as not to generate an interrupt signal for sound source processing.

After the above-described operation, tone generation is executed by an arbitrary sound source system for each sound generation channel based on the transferred sound source processing program. In the above operation, depending on the selected sound source processing program for 8 channels,
Although the program capacities are different, in the present embodiment, the area for the maximum program capacity is secured on the program memory 201 or the program RAM 301, and the above-mentioned program transfer is unconditionally executed for the maximum program capacity. Therefore, although an extra program part is transferred depending on the selected program, the end command is stored at the end of the sound source processing program for eight channels in succession, and by executing it, There is no problem because the subsequent extra program parts are not executed.

Further, the sound source processing program described above includes a program part of the MCPU interrupt processing corresponding to FIG. 10 or a program part of the SCPU interrupt processing corresponding to FIG. Therefore, the program memory 20
Strictly speaking, in the program transfer to 1 and the program transfer to the program RAM 301, the former has a larger number of program steps by the processing corresponding to steps S1012 to S1014 ′ in FIG. The same program corresponding to FIG. 10 is transferred to both the program memory 201 and the program RAM 301. Therefore, in the same program, a special instruction is inserted in the boundary portion near step S1012, and the SCPU of FIG.
The command analysis unit 307 of the program RAM 3
When the above special command is read from 01, the SCP
U Ends the interrupt processing and sends S to MCPU 101
The CPU processing end signal B (see FIG. 1) is output. Therefore,
On the SCPU 102 side, the above-mentioned extra program part is not executed.

As described above, when the tone color is set, the continuous tone generator processing programs for eight channels are collectively loaded from the external memory 116 to the program memory 201 and the program RAM 301, so that which tone generator is used for each tone generation channel. It is not necessary to perform the determination process of whether to generate a musical sound by the method, and the execution time of the interrupt process of FIG. 10 or 11 can be shortened. As a result, it is possible to increase the execution time of the program of the main flow of FIG. 9 for processing the performance information, and to improve the response performance of tone generation. <Aspects of Other Embodiments> In the above embodiment, the performer is shown in FIG.
When the tone color setting operation is performed using the function key 701 of FIG. 9, the sound source processing program transfer command is executed in the function key processing of step S903 of FIG. 9, but it is performed when an operation other than tone color setting is performed. You may do it. Further, it may be configured to be automatically executed when the power is turned on.

Further, in the series of embodiments of the present invention described above, as shown in FIG. 1, the MCPU 101 and the SCPU are
Two CPUs, 102, share the different sounding channels and process them, but the number of CPUs may be one, or three or more.

Further, the input port 2 of the MCPU 101 shown in FIG.
Various operation units can be connected to the instrument 10 in addition to the instrument operation units as shown in FIGS. 7 and 8, whereby various types of electronic musical instruments can be realized. Further, it is easy to realize as a sound source module that inputs performance information from another electronic musical instrument and performs only sound source processing.

[0146]

According to the present invention, the program executing means stores the execution program storage means in advance by the sound source processing program transfer control means at the time of setting a tone color, etc., when the tone generation of each tone generation channel is performed at predetermined time intervals. It is possible to collectively execute the sound source processing programs that are continuous for all the transmitted sound generation channels.

As a result, it is not necessary to perform the discrimination process of which sound source method is used to generate a musical tone for each sounding channel, and the number of branch instructions can be reduced. It is possible to improve the performance of the musical instrument such as increasing the number.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an embodiment according to the present invention.

FIG. 2 is an internal configuration diagram of a master CPU.

FIG. 3 is an internal configuration diagram of a slave CPU.

FIG. 4 is a configuration diagram of a conventional D / A converter unit.

FIG. 5 is a configuration diagram of a D / A converter unit according to the present embodiment.

FIG. 6 is a timing chart in D / A conversion.

FIG. 7 is a layout view of function keys and keyboard keys.

FIG. 8 is an explanatory diagram of keyboard keys.

FIG. 9 is a main operation flowchart.

FIG. 10 is an operation flowchart of MCPU interrupt processing.

FIG. 11 is an operation flowchart of SCPU interrupt processing.

FIG. 12 is a conceptual diagram showing a relationship between a main operation flowchart and interrupt processing.

FIG. 13 is an operation flowchart of sound source processing.

FIG. 14 is a diagram showing a storage area for each sound generation channel on a RAM.

FIG. 15 is a configuration diagram (part 1) of a data format for each sound source method on a RAM.

FIG. 16 is a configuration diagram (part 2) of a data format for each sound source method on the RAM.

FIG. 17 is a diagram showing a buffer area on a RAM.

FIG. 18 is an operation flowchart of sound source processing according to the PCM method.

FIG. 19 is an operation flowchart (No. 1) of sound source processing by the DPCM method.

FIG. 20 is an operation flowchart (No. 2) of the sound source processing by the DPCM method.

FIG. 21 is an explanatory diagram of the principle in the case of obtaining the interpolation value XQ using the difference value D and the current address AF in the PCM method.

FIG. 22 is a difference value D and a current address AF in the DPCM method.
It is a principle explanatory view in the case of calculating interpolation value XQ using.

FIG. 23 is an operation flowchart of sound source processing by the FM system.

FIG. 24 is a diagram showing an algorithm of sound source processing by the FM system.

FIG. 25 is an operation flowchart of sound source processing by the TM method.

FIG. 26 is a diagram showing an algorithm of a sound source processing by the TM method.

27 is a data layout diagram of the external memory 116. FIG.

FIG. 28 is a program memory 201 and a program RAM
3 is a data layout diagram of 301. FIG.

FIG. 29 is an operation timing chart of the sound source processing program transfer.

[Explanation of symbols]

101 Master CPU 102 Slave CPU 103 MCPU External Memory Access Address Latch Unit 104 SCPU External Memory Access Address Latch Unit 105 Access Address Conflict Avoidance Circuit 106 External Memory Selector Unit 107 Left D / A Converter Unit 108 Right D / A Conversion Device section 109 Input port 110 Output port 111, 112 Output terminal 113 Left output terminal 114 Right output terminal 115 External memory data-in terminal 116 External memory 201 Program memory 202 Memory address decoder 203 Interrupt control section 204, 205, 304, 305 RAM address Control unit 206, 306 RAM 207, 307 Command analysis unit 208, 308 ALU unit 209, 309 Multiplier 210 Input port 211 Output port 21 SCPU Internal RAM addressing bus interface 213 Data bus interface for writing to SCPU 214 Data bus interface for reading from SCPU 215 Address bus interface for external memory access 216 External memory data bus interface 217 D / A data transfer bus Interface 218 Program ROM 219 Initial transfer control unit 301 Program RAM 302 RAM address control unit 303 SCPU by MCPU Internal RAM addressing bus interface 310 Write data bus interface by MCPU 311 Read data bus interface to MCPU 312 External memory access Address bus interface 313 External memory data bus interface 31 Gate circuit 401, 501 Latch 402 D / A converter 701 Function key 702 Keyboard key A SCPU Reset release signal (processing start signal) B SCPU processing end signal C Address switching signal Ma SCPU Internal RAM addressing bus Dout MCPU writes to SCPU Data bus Din MCPU reads to SCPU Data bus MA MCPU specifies external memory Address bus SAS CPU specifies external memory Address bus MD MCPU reads from external memory Data bus SD SCPU reads from external memory PRG program Data ADR address signal UD up / down instruction signal ~ W write signal

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kosuke Shiba 3-2-1 Sakaemachi, Hamura-cho, Nishitama-gun, Tokyo Inside Casio Computer Co., Ltd. Hamura Technical Center (72) Kazuo Ogura Sakae-cho, Hamura-cho, Nishitama-gun, Tokyo 3-2-1, Casio Computer Co., Ltd., Hamura Technology Center (72) Inventor Jun Hosoda 3-2-1, Sakaemachi, Hamura-cho, Nishitama-gun, Tokyo Casio Computer Co., Ltd., Hamura Technology Center (56) References Special Kaihei 2-179696 (JP, A) JP 59-168493 (JP, A)

Claims (2)

(57) [Claims] 1. A musical tone waveform generator including program executing means for executing a tone generator processing program of an arbitrary tone generator system among a plurality of tone generator systems at predetermined time intervals to generate a tone signal for each of a plurality of tone generator systems. In the above, a sound source processing program that is continuously executed for all sound generation channels, and a plurality of sets of storage program storage means for storing a plurality of sets for each combination of sound generation methods of all sound generation channels, and the program execution for each predetermined time interval. An execution program storage means for storing a sound source processing program continuously executed for all sound generation channels by means, and an arbitrary sound source processing program continuously executed for all sound generation channels from the storage program storage means. And a sound source processing program transfer control means for reading out the set and transferring the set to the execution program storage means. Tone waveform generation apparatus characterized by. 2. A plurality of processors including a program executing means for executing a sound source processing program of an arbitrary sound source method among a plurality of sound source methods for a plurality of sound source channels at predetermined time intervals to generate a musical tone signal. In the musical tone waveform generating apparatus, a storage program storage means for storing a plurality of sound source processing programs continuously executed for all sound generation channels for each processor for each combination of sound source systems of all sound generation channels. An execution program storage means is provided for each processor, and stores a sound source processing program that is continuously executed for all sound generation channels of each processor by the program execution means of each processor at each predetermined time interval. And a sound source processing program continuously executed for all the sound generation channels from the storage program storage means A sound source processing program transfer control means for reading out any set of the above and transferring it to the execution program storage means of each processor.