JP2004177981A - Musical sound generating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a musical sound generating device, which can generate a musical sound having channels more than channels limited depending upon the data transfer speed of a storage device according to waveform data stored in the storage device whose data transfer speed is slow, and to provide a storage medium. <P>SOLUTION: When a cache hit of waveform data whose sounding is indicated is detected, a musical sound is generated by using the waveform data held in a cache memory 11. When a cache miss of waveform data whose sounding is indicated is detected, the waveform data regarding the sounding indication are read out of a waveform memory 10 and transferred to the cache memory 11 and the waveform data having been transferred are used to generate a musical sound. Further, when timbre switching is indicated, whether waveform data used preferentially for a switching-indicated timbre are held or not in the cache memory 11 is detected and when the waveform data are not held in the cache memory 11, the waveform data are read out of the waveform memory 10 and transferred to the cache memory 11. <P>COPYRIGHT: (C)2004,JPO

Description

  The present invention relates to a musical sound generating apparatus for generating musical sounds having more channels than the number of channels limited depending on the data transfer speed of a storage device based on waveform data stored in a storage device having a low data transfer speed. About.

2. Description of the Related Art Conventionally, the following are known as tone generators that generate a tone based on waveform data stored in a storage device (including a waveform memory (ROM)) having a low data transfer rate. That is,
(1) By interpolating the waveform samples read from the waveform memory, in the musical sound generating device that generates the target musical sound waveform, the read waveform samples used for interpolation are stored in the cache memory, and the cached waveform samples are stored in the cached waveform samples. (2) Load waveform data stored in a hard disk, which is a storage device having a low data transfer rate, into a RAM having a low capacity and a high data transfer rate, and load the waveform data A musical sound generating device that generates musical sounds based on the above.

  However, in the above-described conventional musical tone generator (1), when a musical sound waveform to be generated advances and a waveform sample for interpolating and generating this musical sound waveform is not held in the cache memory, the waveform sample is converted into a waveform. Since the data must be read from the memory, the number of musical sound waveform channels to be generated eventually depends on the data transfer rate of the waveform memory.

  Also, in the above-mentioned conventional musical tone generating device (2), when the tone generation is instructed, if the waveform data corresponding to the instructed tone is not loaded on the RAM, the tone is generated. could not.

  The present invention has been made paying attention to this point, and based on waveform data stored in a storage device having a low data transfer rate, the number of channels limited depending on the data transfer rate of the storage device. An object of the present invention is to provide a musical sound generating apparatus capable of generating musical sounds with a larger number of channels.

  In order to achieve the above object, a musical sound generating apparatus according to claim 1, a first storage unit having a predetermined data transfer rate, each storing a plurality of waveform data assigned waveform IDs, and a data transfer rate The second storage means faster than the first storage means, the third storage means for storing the waveform ID of the waveform data stored in the second storage means, and a plurality of waveform data are simultaneously read out The waveform data related to the readout instruction is input to the readout means for instructing the read instruction and whether each waveform data related to the readout instruction input by the input means is stored in the second storage means. First discrimination means for discriminating on the basis of the waveform ID stored in the third storage means and the waveform relating to the readout instruction as a result of discrimination by the first discrimination means When it is determined that the data is not stored in the second storage means, in response to the read instruction, the waveform data related to the read instruction is read from the first storage means and the second storage means And the first transfer means for storing the waveform ID of the transferred waveform data in the third storage means, and the reading from the second storage means in response to the input read instruction. Reading out a plurality of waveform data related to the instruction, and generating a plurality of musical sounds simultaneously based on the read-out plurality of waveform data, and transferring the waveform data by the first transfer unit; It is characterized in that it can be executed in parallel with the reading of the waveform data by the tone generation means.

  Here, the first storage means is typically a waveform memory (ROM). However, the first storage means is not limited to this, and any storage means having a low data transfer speed, such as a hard disk or an MD, may be used. There may be. The second storage unit is typically a cache memory, but is not limited thereto, and may be a RAM as long as the data transfer rate is high. The above is the same even if the claims change.

Preferably, the transfer of the waveform data by the first transfer means and the reading of the waveform data by the tone generation means proceed asynchronously with each other, and the first transfer means performs transfer of the waveform data by block transfer and It is characterized in that it is performed by a highly efficient transfer method including burst transfer.

  Preferably, before the first transfer means transfers the waveform data to the second storage means, the second storage means has sufficient free space for storing the waveform data. A second discriminating unit for discriminating whether or not there is a sufficient free area by the second discriminating unit, and at least one of the waveform data already stored in the second storage unit Erasing means for erasing one waveform data to secure a free space necessary for storing the waveform data, and erasing the waveform ID of the erased waveform data from the third storage means It is characterized by that.

  More preferably, the first transfer means sends a plurality of waveform data in parallel from the first storage means to the second storage means within the limitation of the data transfer speed of the first storage means. It is possible to transfer it.

  Further preferably, the readout instruction includes speed designation information for designating a readout speed of each waveform data related to the readout instruction, and the tone generation unit is configured to specify the waveform data as a corresponding speed designation. Reading is performed at a reading speed designated by the information to generate a musical tone, and the first transfer means controls the transfer speed for each waveform data to be transferred based on the corresponding speed designation information. .

  Preferably, the transfer of the waveform data by the first transfer means and the reading of the waveform data by the tone generation means proceed asynchronously with each other, and the first transfer means is the first storage means. A plurality of waveform data can be transferred in parallel from the first storage means to the second storage means at different speeds within the limitation by the data transfer speed.

  More preferably, timbre switching instructing means for instructing timbre switching, and waveform data that is preferentially used in the instructed timbre when the timbre switching is instructed by the timbre switching instructing means. A third discriminating means for discriminating whether or not the data is stored on the basis of the waveform ID of the waveform data used preferentially and the waveform ID stored in the third storage means; When the waveform data used preferentially is not stored in the second storage means as a result of the determination by the determination means, the waveform data is read from the first storage means in units of waveform data, and the second data is read out. In addition to the transfer to the storage means, there is further provided a second transfer means for storing the waveform ID of the transferred waveform data in the third storage means.

  According to the first aspect of the present invention, when the waveform data related to the read instruction is stored in the second storage means, the waveform data related to the read instruction is stored based on the stored waveform data. When not stored in the second storage means, the waveform data is read from the first storage means, transferred to the second storage means, and then a musical tone is generated based on the stored waveform data. In other words, when generating a musical tone, the waveform data is supplied at high speed using only the waveform data stored in the second storage means having a high data transfer speed. However, the limitation on the number of tone generation channels depending on the low-speed first storage means can be eliminated.

  Further, since the transfer of the waveform data from the first storage means to the second storage means and the generation of the musical sound based on the waveform data read from the second storage means are performed asynchronously, the second storage The method of transferring the waveform data to the means is not limited, and the most efficient transfer method such as block transfer or burst transfer can be used.

  According to the fifth aspect of the present invention, the readout instruction includes speed designation information for designating a readout speed of each waveform data related to the readout instruction, and the musical sound generating means stores the waveform data. The first transfer means controls the transfer speed for each waveform data to be transferred based on the corresponding speed specifying information for each waveform data to be transferred. Since it did in this way, the state that the waveform sample which should be read to the 2nd memory | storage means in the middle of sounding is not transferred can be eliminated, and a musical sound can be reproduced | regenerated stably.

  According to the seventh aspect of the present invention, when the timbre switching is instructed, if the waveform data used preferentially in the instructed timbre is not stored in the second storage means, the waveform data is Since the data is read from the first storage means and transferred to the second storage means, the waveform data that is used for the first time can be efficiently cache hit.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of a musical sound generating apparatus according to an embodiment of the present invention.

  As shown in the figure, the musical tone generating apparatus of the present embodiment includes a panel switch 1 having a plurality of switches for inputting various types of information, and displays various types of information such as a large liquid crystal display (LCD) and Display device 2 provided with a light emitting diode (LED), CPU 3 for controlling the entire device, ROM 4 for storing a control program executed by CPU 3 and various table data, performance data, various input information and calculation results RAM 5 for temporarily storing, etc., timer 6 for measuring interrupt time and various times in timer interrupt processing, hard disk device 7 for storing various application programs and various data including the control program, and external MIDI (Musical instrument digital interface) Input signal or output MIDI signal to outside And a register 9 having an area for storing data such as ch (channel) data (described later using FIG. 2) and C (cache) management data (described later using FIG. 3). These components 1 to 9 are connected to each other via a bus 18.

  As described above, the hard disk device 7 can also store a control program executed by the CPU 3. When the control program is not stored in the ROM 4, the hard disk device 7 stores the control program in the hard disk and reads it into the RAM 5. Thus, the CPU 3 can be caused to perform the same operation as when the control program is stored in the ROM 4. In this way, control programs can be easily added and upgraded.

  The MIDI interface 8 is not limited to a dedicated interface, and may be configured by a general-purpose interface such as RS-232C, USB (Universal Serial Bus), IEEE 1394 (I Triple 1394) or the like. In this case, data other than MIDI messages may be transmitted and received simultaneously.

  The register 9 stores waveform data stored in the waveform memory (ROM) 10 having a large capacity (for example, 128 Mword) and a low data transfer rate (for example, 6 Mword / second), and a small capacity (for example, 4 Mword) and data. A cache control unit 12 that loads into the cache memory 11 having a high transfer rate (for example, 66 Mword / second) or reads out the waveform data loaded in the cache memory 11, and one sample when reading out the waveform data By accumulating the F number FN indicating the advance amount of the address for each sound generation channel, the phase generator 14 for generating the read address (relative address) of the waveform data for each channel is read from the cache memory 11. DSP (digital signal p) for processing processed waveform data rocessor) 15 is connected.

  Here, when generating a musical sound, the musical sound generating apparatus of the present embodiment always reads out waveform data serving as a reference for generating the musical sound from the cache memory 11 and generates a musical sound based on the waveform data. When the waveform data serving as a reference for generating the musical sound is not held in the cache memory 11, that is, when a cache miss occurs, the waveform data is read from the waveform memory 10 and transferred to the cache memory 11. The waveform data is read from the cache memory 11 to generate a musical sound. At this time, as will be described later, the transfer speed of the waveform data from the waveform memory 10 to the cache memory 11 is set faster than the advance amount (read speed) of the read address of the waveform data on the cache memory 11. In the middle of the process, the waveform sample to be read out to the cache memory 11 is not transferred.

  In the present embodiment, when the sampling frequency of the apparatus is 50 kHz, for example, and the decimal part is included in the read address generated by the phase generator 14, the waveform sample at that address is calculated by linear interpolation. Since it is necessary to read two waveform samples per cycle, the sampling frequency is substantially 100 kHz.

  If one waveform sample (with a data capacity of 1 word) can be read out in one cycle of the sampling frequency of 100 kHz, a musical sound for one channel can be generated. Therefore, as in this embodiment, a cache memory is always used. 11, when the stored waveform data (waveform sample) is read and used for tone generation, it is possible to generate tone for 66 Mword / second ÷ 100 kword / second / ch = 660 ch.

  However, in this embodiment, since data transfer of a maximum of 6 Mword / second, that is, data transfer of waveform data from the waveform memory 10 to the cache memory 11 is also performed within one sampling period, 6 Mword / second ÷ 100 kword / second It is necessary to subtract from the above-mentioned 660 ch for / ch = 60 ch. Therefore, the musical tone generation apparatus according to the present embodiment can generate a maximum of 600 ch.

  Based on the channel data for each tone generation channel (the maximum number of channels is 600 channels as described above) stored in the register 9, the phase generator 14 reads the waveform data for each channel (real value). And the integer part is supplied to the cache control unit 12 and the decimal part is supplied to the DSP 15.

  Based on the C management data stored in the register 9, the cache control unit 12 determines whether or not the waveform data to be read by each channel is stored in the cache memory 11. At the same time as reading of the waveform data in the channel is started, the waveform data is read from the waveform memory 10 and transferred to the cache memory 11, while corresponding to the integer part of the read address generated in the channel when stored. The waveform data at the position (and the next position) is read from the cache memory 11 and supplied to the DSP 15.

  Here, the waveform data is read from the waveform memory 10 in block units (one block is 1 kword in the present embodiment) and loaded into the cache memory 11. Normally, since the capacity of the waveform data to be read is larger than 1 kword, a plurality of blocks are loaded into the cache memory 11, but when there is no free space in the cache memory 11 where the capacity of the plurality of blocks is gathered, each block is loaded. Are stored discretely on the cache memory 11. On the other hand, the phase generation unit 14 generates a read address as a continuous address of the waveform data. For this reason, by defining a virtual address for the real address on the cache memory 11 and rearranging this virtual address (virtual address for each block), a waveform that still exists discretely at the real address. The data addresses are seemingly continuous. This type of technology is called garbage collection. This eliminates the need to transfer the data stored on the cache memory 11 when collecting the free areas, and thus the processing can be performed at high speed.

  The cache control unit 12 is connected to the cache memory 11 via an address conversion unit 13 that converts the virtual address into a real address on the cache memory 11 in order to read out target waveform data from the cache memory 11.

  The DSP 15 performs tone generation channel processing, effect processing, and mixer processing, and outputs digital musical tone data subjected to these processes to a DAC (digital to analog converter) 16. The DAC 16 receives the digital musical tone data supplied from the DSP 15. It is converted into an analog musical sound signal and converted into sound via a sound system 17 including an amplifier and a speaker.

  Here, examples of the sound generation channel processing include inter-sample interpolation processing, timbre filter processing, volume envelope processing, and channel accumulation processing.

  In the inter-sample interpolation processing, interpolation calculation is performed based on the waveform data supplied from the cache control unit 12 and the decimal part of the read address supplied from the phase generation unit 14 to generate waveform samples of the interpolated waveform data. In the present embodiment, the cache control unit 12 supplies two waveform samples for each channel to the DSP 15, and the DSP 15 generates an interpolation sample by linear interpolation based on the two waveform samples. Of course, waveform samples read in the past may be stored, and higher order interpolation may be performed based on this waveform sample and the newly read waveform sample.

  In the timbre filter process, timbre control is performed on the interpolated waveform data by, for example, low-pass filter calculation. This low-pass filter calculation is performed based on the cut-off characteristics, resonance characteristics, etc. supplied as parameters.

  In the volume envelope processing, the time change (envelope) of the volume from the rising edge to the falling edge of the musical tone is given to the waveform data subjected to the timbre filter processing. This volume envelope process is also performed based on EG (envelope generator) control information supplied as a parameter.

  In the channel accumulation process, the waveform data with the envelope is subjected to level control for each effect process (in this embodiment, there are three types of processes, chorus process, reverb process, and equalizer process). Accumulate channels and output to each effect process.

  In the chorus process, a chorus effect is imparted to the waveform data output for this process.

  In the reverb process, a reverberation effect is given to the waveform data output for this process.

  In the mixer processing, each volume of the waveform data to which the chorus effect is applied and the waveform data to which the reverberation effect is applied is controlled, and the waveform data that has been subjected to the volume control and the waveform data that is output for the equalizer processing are mixed. .

  In the equalizer process, the frequency characteristic of the waveform data mixed by the mixer process is processed and controlled.

  Waveform data whose frequency characteristics are processed and controlled is supplied from the DSP 15 to the DAC 16.

  As described above, each of the phase generation unit 14 and the DSP 15 needs to perform processing for generating instruments for a maximum of 600 channels in one sampling period in a time division manner. In order to realize this processing, each circuit may be parallelized or pipelined as necessary. That is, a configuration in which each process is pipelined into a plurality of stages with time division 600 ch, a configuration in which two processes are paralleled and each of which is pipelined into a plurality of stages with each time division 300 ch, and a plurality of processes are parallelized in four and each with a time division 150 ch It is possible to adopt a configuration such as a pipeline in stages. Generally, the number of pipeline stages can be reduced by increasing the number of parallelizations.

  FIG. 2 is a diagram showing a data format of the ch data stored in the register 9.

  Each ch data is composed of a plurality of data necessary for generating a musical tone in the sound generation channel, and the register 9 is provided with areas ch1 to ch600 in which data for 600 ch is stored. Since the data format of each ch data is common, the data format of ch3 ch data is representatively illustrated in FIG.

  In the figure, the ch data includes an F number FN, an overall volume of a generated musical tone, a waveform ID for specifying waveform data on the waveform memory 10 used for musical tone generation, and a waveform memory 10 ( Alternatively, a relative address of a predetermined position (for example, a read start position, a loop read start position, and a loop read end position) with reference to the start storage position (address) of the waveform data (corresponding to the waveform ID) on the cache memory 11 Information, DCF (digital controlled filter) control information (including the cutoff characteristics and resonance characteristics) that are parameters used for filter calculation in the timbre filter processing, and parameters used for volume control in the volume envelope processing EG control information, other information used for tone generation, and note on / off status It is composed of ON / OFF data indicated by “0” and “1”.

  As described above, the F number FN indicates the advance amount of the address per sample when the waveform data is read. If the pitch of the musical tone to be generated and the waveform data used for the generation are determined, the F number FN Is determined. The phase generator 14 accumulates the F number FN for each channel in synchronization with the sampling frequency of the system (in this embodiment, 50 kHz as described above), and reads the waveform data for each channel. Generates an address (relative address).

  Each waveform data stored in the waveform memory 10 is given an ID, and the target waveform data can be specified on the waveform memory 10 by designating the waveform ID in the ch data.

  The on / off data starts to generate a tone of the channel when the value changes from “0” to “1”, and when the value changes from “1” to “0”, This is for instructing the DSP 15 to start the release.

  FIG. 3 is a diagram showing a data format of the C management data stored in the register 9.

  The C management data is composed of a plurality of data necessary for managing the state of the waveform data stored in the cache memory 11, and the register 9 is provided with areas cw1 to cw600 for storing data for 600 waveforms. It has been. Since the data format of each C management data is the same, the data format of the C management data of cw (cache wave) 3 is illustrated in FIG.

  In the figure, the C management data includes a waveform ID that operates in the same manner as the waveform ID in the channel data, a transfer state TS indicating the transfer state of the waveform data to the cache memory 11, and the waveform data to the cache memory 11. Of the waveform data, the cache storage position virtual address representing the storage position of the waveform data on the cache memory 11 with a virtual address, and the data transferred to the cache memory 11 of the waveform data The transferred size indicating the data size, the total size indicating the total data size of the waveform data, and the storage location of the waveform data on the waveform memory 10 are the real addresses (the waveform data is linear on the normal waveform memory 10 (continuous Waveform memory storage location indicated by a linear address) It is constituted by a near-address.

  The transfer state TS takes any integer value from “0” to “2”, and each integer value means the following state.

0: The waveform data indicated by the waveform ID is not used for music generation 1: The waveform data indicated by the waveform ID is being transferred to the cache memory 11 2: The waveform data indicated by the waveform ID is stored in the cache memory 11 Transfer completed state The transfer rate TA takes any integer value from “0” to “120”, and the number of blocks transferred per second (in this embodiment, 50 blocks = 50 kwords) ) Is one unit. For example, TA = 0 indicates a state in which data transfer to the cache memory 11 is not performed, TA = 1 indicates a state in which data transfer of 50 blocks / second to the cache memory 11 is performed, and TA = 2 indicates a cache transfer state. This indicates a state in which data transfer of 100 blocks / second to the memory 11 is performed. As the value set as the transfer speed TA increases, the number of blocks transferred per second, that is, the transfer speed increases. It has become.

  Here, the unit of the number of blocks transferred per second is set to 50 blocks when the F number FN is set to “1” (at the system sampling frequency (= 50 kHz)). This is because the speed corresponds to the musical sound reproduction (when each waveform sample of the waveform data is read).

Further, as described above, the maximum transfer rate TA can be “120”. This is because the data transfer rate from the waveform memory 10 is 6 Mword / second in the present embodiment. Therefore, when there are a plurality of waveform data to be transferred to the cache memory 11, it is necessary to distribute “120”. (In other words, the total value of the transfer rates TA assigned to each load does not exceed “120”.) As a method of distributing, for example, the following method can be considered. That is,
(1) A larger integer value is preferentially assigned to the load during sound generation than the load during tone switching. (2) For the load during sound generation, the F number FN of the sound generation channel using the waveform data. (3) An arbitrary integer value of 120 or less may be assigned to the load at the time of timbre switching (for example, the total of transfer rates TA assigned to other loads is When “120” has been reached, the transfer speed TA may be set to “0” for the load at the time of the remaining tone switching)
Here, in the above (1), the load at the time of sound generation means that the waveform data corresponding to the musical sound that is about to be sounded is not stored in the cache memory 11 and the waveform data is read from the waveform memory 10. Reading and loading into the cache memory 11. The load at the time of timbre switching is, for example, a waveform that is used preferentially (for example, most frequently used) in the instructed timbre when data instructing timbre switching is supplied as performance data, for example. In the present embodiment, when the data is not stored in the cache memory 11, the waveform data is read from the waveform memory 10 and loaded into the cache memory 11.

  In the above (2), the integer value corresponding to the F number FN is, for example, a value obtained by rounding up the decimal point of the F number FN, and is “2” when FN = 1.5. The transfer rate TA is set to an integer value greater than or equal to the integer value according to the F number FN because one unit of the transfer rate is set based on the transfer rate required when the F number FN = 1. Therefore, if the F number FN is set to a value larger than “1”, if the waveform data is not transferred to the cache memory 11 at a transfer rate corresponding to the F number FN, the read address advance amount is the waveform that has been transferred. This is because the sample address may be exceeded, and at this time, the musical sound cannot be reproduced.

  Furthermore, in the above (3), the setting value of the transfer rate TA for the load at the time of timbre switching is not provided with the condition as in (2) above, because the tone is actually generated with the timbre from the timbre switching instruction. This is because there is time to spare before it is done.

  As described above, the cache storage position virtual address represents the storage position of the waveform data on the cache memory 11 with a virtual address, and is discretely arranged in the real address space of the cache memory 11. Each block constituting the waveform data is continuously rearranged on the virtual address space. In the present embodiment, each waveform sample of the waveform data is read out based on the cache storage position virtual address. Therefore, the phase generation unit 14 simply accumulates the F number FN and sets the read address. Can be generated. The cache control unit 12 automatically rearranges the data blocks in the virtual address space. Based on the result, the cache control unit 12 converts the virtual address and the real address to each other. The address conversion table provided in the conversion unit 13 is rewritten. Since the control processing executed by the cache control unit 12 is described in detail in Japanese Patent Laid-Open No. 6-35473, description thereof is omitted. By adopting the hardware address conversion described in this publication, access to the cache memory 11 by the virtual address can be executed without time delay.

  The control process executed by the musical tone generating apparatus configured as described above will be described in detail with reference to FIGS.

The tone generation device of the present embodiment mainly performs the following control processing. That is,
(1) A cache hit or a cache miss is detected in the waveform data for which sound generation is instructed. When a cache hit is detected, a musical tone is generated using the waveform data held in the cache memory 11, and a cache miss is detected. When detected, the waveform data related to the sound generation instruction is read from the waveform memory 10, transferred to the cache memory 11, and a musical tone is generated using the transferred waveform data. (2) When timbre switching is instructed, It is detected whether or not the waveform data that is preferentially used for the tone for which switching is instructed is held in the cache memory 11, and when this waveform data is not held in the cache memory 11, this waveform data Is read from the waveform memory 10 and transferred to the cache memory 11 (3) (1) and (2) above Asynchronous transfer of waveform data from the waveform memory 10 to the cache memory 11 and reading of waveform data (waveform samples) held in the cache memory 11 for generating musical sounds for each channel (4) Caching of waveform data to the cache memory 11 is performed in units of one waveform (however, it is not necessary to transfer waveform data from the waveform memory 10 in units of one waveform, and in the present embodiment, the waveform is divided into a plurality of waveforms. In short, cache management such as determining cache hits and loading instructions when there is no hit is not for each sample or multiple samples in one waveform. In other words, the waveform data is stored in the cache memory 11 as a unit. It may be a discrete or may be continuous.)
(5) The transfer at the time of a cache miss in the above (1), that is, the transfer of waveform data from the waveform memory 10 to the cache memory 11 is performed faster than the waveform sample reading speed (address advance amount) at the time of tone generation. Details of the control processes (1) to (5) will be described.

  FIG. 4 is a flowchart showing the procedure of the timbre switching event process executed by the tone generator of the present embodiment, particularly the CPU 3, and realizes the control process (2). This process is started when a timbre switching event is supplied as performance data.

  In the figure, first, a timbre number (new timbre number) of a new timbre indicated by a timbre switching event is acquired, and an area TC secured at a predetermined position in the RAM 5 (hereinafter, the contents of this area are referred to as “timbre TC”). (Step S1).

  Next, among the various waveform data used in the timbre TC, the waveform ID of the waveform data to be loaded into the cache memory 11 is determined according to the priority (step S2).

  Then, it is determined whether or not the waveform data corresponding to the determined waveform ID is to be newly loaded into the cache memory 11 (step S3). Here, whether or not it should be newly loaded is determined as follows.

  That is, it is checked whether or not the same waveform ID as the waveform ID determined in step S2 is in the C management data in which the transfer state TS is other than “0”. It is determined that the waveform data is to be newly loaded.

  In step S3, when the target waveform data is being transferred to the cache memory 11 or has been transferred and there is no waveform data to be newly loaded, the tone color switching event processing is immediately terminated, while the new waveform data is loaded. When there is power waveform data, a load instruction processing subroutine (described later with reference to FIG. 6) for instructing loading of the waveform data into the cache memory 11 is executed (step S4), and then the timbre switching event process is terminated. .

  Here, as will be described later, the load instruction processing subroutine is configured so that the low-speed load instruction and the high-speed load instruction can be switched in one subroutine according to the value set in the transfer speed TA. The low speed load instruction is issued by setting a value corresponding to “low speed” to the transfer speed TA. This is because it is not necessary to load quickly when switching timbres as described above.

  FIG. 5 is a flowchart showing a procedure of note-on event processing executed by the CPU 3, and realizes the control processing (1). This process is activated when a note-on event is supplied as performance data.

  In the figure, first, a note number and (&) velocity are obtained from a supplied note-on event, and each area NN secured at a predetermined position in the RAM 5 (hereinafter, the contents of this area are referred to as “note number NN”). ) And area VEL (hereinafter, the contents of this area are referred to as “velocity VEL”) (step S11).

  Next, the waveform ID corresponding to the note number NN and the tone color TC (this tone color TC is already set when the note-on event is supplied) is detected (step S12).

  Then, it is determined whether or not the waveform data of the detected waveform ID is loaded on the cache memory 11 (step S13). This determination is performed by the same method as the determination in step S3.

  If the target waveform data is not loaded on the cache memory 11 in step S13, the load instruction processing subroutine (however, high-speed load instruction) is executed (step S14) after step S15, in the same manner as in step S4. On the other hand, when the target waveform data is loaded on the cache memory 11, the process skips step S14 and proceeds to step S15.

  In step S15, an empty channel is detected and sound generation is assigned to that channel.

  In subsequent step S16, various parameters corresponding to the tone color TC and the note number NN are set in the assigned channel. Specifically, in the ch data storage area for 600 channels of the register 9, the F number FN, waveform ID, relative address, DCF control information, EG control information, and other information are stored in the ch data area corresponding to the assigned channel. Write.

  Then, note-on is set for the channel (step S17), and then the note-on event processing is terminated. Here, note-on is set by setting note-on / off data in the ch data area in step S16 to note-on (“1”).

  FIG. 6 is a flowchart showing a detailed procedure of the load instruction processing subroutine of steps S4 and S14. The control process (5) is realized by the load instruction process.

  In the figure, first, among the C management data storage areas for 600 waveforms in the register 9, the smallest k in the area cwk (k is an integer value of 1 to 600) in which the transfer state TS is “0”. Obtain (step S21).

Next, an area on the cache memory 11 for storing the waveform data indicated by the determined (or detected) waveform ID is allocated (step S22). This area allocation is performed as follows, for example. That is,
(1) A plurality of waveform data stored in the cache memory 11 is left-justified on the virtual address. (2) An area for writing the waveform data indicated by the waveform ID is secured in a free area formed thereafter. ) If there is not enough free space, the area where the waveform data not currently used is stored is released, and the above processes (1) and (2) are repeated.

  In the subsequent step S23, necessary parameters are set in the area cwk. Specifically, the waveform ID, transfer state TS, cache storage location virtual address, total size, and waveform memory storage location linear address are written.

  Then, according to the priority of the waveform data to be loaded at the same time, the transfer rate TA of each waveform data is assigned (distributed) (step S24), and then this load instruction process is terminated. Here, the distribution is performed by the method described above, and each distributed transfer rate TA is written in the corresponding transfer rate TA area in the area cwk. As a result, a transfer speed corresponding to “low speed” is set in the timbre switching event process, and a transfer speed corresponding to “high speed” is set in the note-on event process. Note that “low speed” and “high speed” are relative expressions of the transfer speed in the timbre switching event process and the note control event process. As a result of the distribution, a larger speed is required for the transfer in the note on event process. It means to be assigned. Even when “low speed” is set, all “120” is assigned to the transfer speed TA if no other transfer is performed.

  FIG. 7 is a flowchart showing the procedure of the transfer process executed by the cache control unit 12, and implements the control processes (3) and (4). This transfer process is activated when a load instruction is issued by the load instruction process subroutine of FIG.

  In FIG. 7, first, the minimum k (initial value) is detected in the area cwk in which the load is instructed (TS = 1), and the area L (hereinafter referred to as “index L”) secured at a predetermined position in the RAM 5 is detected. (Referred to as ")" (step S31).

  Then, the transfer speed TA (L) in the area cwL indicated by the index L is acquired and stored in a software counter area CNT (hereinafter, this content is referred to as “counter CNT”) secured at a predetermined position in the RAM 5 (step CNT). S32).

  Next, the waveform data corresponding to the waveform ID (L) in the area cwL indicated by the index L is read from the waveform memory 10 and transferred to the area on the cache memory 11 allocated in step S22 (step S33). This transfer is performed for one block or a plurality of blocks, that is, blocks for which a transfer rate of 50 blocks / second is obtained.

  In a succeeding step S34, it is determined whether or not the transfer of the waveform data corresponding to the waveform ID (L) is completed. This determination is performed by comparing the transferred size in the area cwL with the total size.

  If the transfer of the waveform data corresponding to the waveform ID (L) is not yet completed in step S34, the counter CNT is decremented by “1” (step S35), and then whether or not the counter CNT is “0”. Is determined (step S36).

  If CNT ≠ 0 in step S36, there is a block of waveform data to be transferred, so the process returns to step S33 to repeat transfer of one or more blocks.

  On the other hand, when the transfer of the waveform data corresponding to the waveform ID (L) is completed in step S34, “2” is set in the transfer state TS (L) in the area cwL (step S37), and then the transfer state TS is It is determined whether or not there is another “1” area cwk (step S38).

  In step S38, when there is no other area cwk whose transfer state TS is “1”, this transfer process is terminated. On the other hand, when there is another area cwk whose transfer state TS is “1”, the area cwk is between the areas cwk. Then, the transfer rate TA is redistributed (step S39). For example, the redistribution is performed in consideration of the trigger factor and the priority among the waveform data being transferred. Then, the transfer rate TA redistributed in this way is written in the corresponding transfer rate TA area.

  In subsequent step S40, in order to obtain the waveform data to be transferred next, in the area cwk whose transfer state TS is "1", the next k (here, the next "k") of the area cwL transferred in the previous column. For example, when the region where the transfer state TS is “1” is k = 2, 5, 10, 25, and the “L” of cwL is “2”, the next “k” is selected. Is "5", and if "L" is "25", the next "k" is "2") and set to the index L. Similarly to step S32, After obtaining the transfer rate TA (L) in the area cwL indicated by the index L and storing it in the counter CNT (step S41), the process returns to step S33.

  On the other hand, if CNT = 0 in step S36, there is no waveform data block to be transferred, and the process proceeds to step S40.

  As described above, in the present embodiment, when generating a musical sound, waveform data is supplied at high speed using only the waveform data stored in the cache memory, so that the data transfer rate of the waveform memory is slow. The limitation of the number of sound generation channels depending on the can be solved.

  When a cache hit occurs, a musical tone is generated using the waveform data held in the cache memory, so there is no need to transfer the waveform data from the waveform memory to the cache memory.

  When the waveform data for which sound generation is instructed is missed, it is transferred to the cache memory with higher priority than the waveform data for which loading has been instructed due to other factors, and the lower limit of the transfer speed is set to the F number of the waveform data. Therefore, the state that the waveform sample to be read to the cache memory is not transferred during the sound generation can be solved, and the musical sound can be reproduced stably.

  Since the progress of the waveform sample read address and the transfer of the waveform data from the waveform memory to the cache memory are performed asynchronously, the transfer method of the waveform data to the cache memory is not limited. For example, block transfer, burst transfer, etc. An efficient transfer method can be used.

  Since the caching of the waveform data to the cache memory is performed in units of one waveform, that is, it is not a method of dividing the waveform data and caching only a part thereof, so that the data management becomes simple.

  Since the waveform data with high priority is previously stored in the cache memory in accordance with the tone color selection, the waveform data to be used for the first time can be efficiently cache hit.

  In this embodiment, a waveform memory (ROM) is used as a storage device for storing waveform data. However, the present invention is not limited to this, and a randomly accessible hard disk device or MD device may be used. In this case, first, only the head portions of all waveform data are stored in the cache memory, and thereafter, the used waveform and necessary waveforms are sequentially transferred from the storage device to the cache memory.

  In the present embodiment, waveform data having a high priority is loaded when a tone color is selected. However, the present invention is not limited to this, and waveform data that is likely to be used later in accordance with changes in the performance range, tempo, etc. The predicted waveform data may be loaded in advance. Alternatively, the waveform data that the player wants to use in the future may be designated prior to the point of use, and the designated waveform data may be loaded in advance.

  Furthermore, in the present embodiment, when transferring the waveform data read from the waveform memory to the cache memory, the so-called full associative method is adopted as an arbitrary place where the transfer location is vacant. Either a map method or a set associative method may be adopted.

  A program in which a storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or apparatus, and a computer (or CPU 3 or MPU) of the system or apparatus is stored in the storage medium. It goes without saying that the object of the present invention can also be achieved by reading and executing the code.

  In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium storing the program code constitutes the present invention.

  As a storage medium for supplying the program code, for example, a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM 4 or the like is used. be able to. Further, the program code may be supplied from a server computer via another MIDI device or a communication network.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also the OS running on the computer based on the instruction of the program code performs the actual processing. It goes without saying that the case where the functions of the above-described embodiment are realized by performing part or all of the above and the processing thereof is included.

  Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that the case where the CPU 3 or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

It is a block diagram which shows schematic structure of the musical tone production | generation apparatus which concerns on one embodiment of this invention. It is a figure which shows the data format of the ch data stored in the register | resistor of FIG. It is a figure which shows the data format of the C management data stored in the register | resistor of FIG. FIG. 2 is a flowchart showing a procedure of tone color switching event processing executed by the musical tone generating apparatus of FIG. It is a flowchart which shows the procedure of the note-on event process which CPU of FIG. 1 performs. 6 is a flowchart showing a detailed procedure of a load instruction processing subroutine of FIG. 4 or FIG. 5. It is a flowchart which shows the procedure of the transfer process which the cache control part of FIG. 1 performs.

Explanation of symbols

3 CPU (first determination means, second determination means, third determination means, first transfer means, second transfer means, tone color switching instruction means, erasure means), 9 register (third storage means) ),
10 waveform memory (first storage unit), 11 cache memory (second storage unit), 12 cache control unit (first transfer unit, second transfer unit, musical tone generation unit), 13 address conversion unit (first unit) 1 transfer means, second transfer means, tone generation means), 15 DSP (music tone generation means)

Claims (7)

First storage means for storing a plurality of waveform data each assigned a waveform ID and having a predetermined data transfer rate;
A second storage means having a data transfer rate higher than that of the first storage means;
Third storage means for storing the waveform ID of the waveform data stored in the second storage means;
Input means for inputting a read instruction for instructing to simultaneously read a plurality of waveform data;
Whether or not each waveform data related to the read instruction input by the input means is stored in the second storage means is stored in the waveform ID of the waveform data related to the read instruction and the third storage means. First discriminating means for discriminating based on the waveform ID,
When it is determined that the waveform data related to the read instruction is not stored in the second storage means as a result of the determination by the first determination means, the waveform data related to the read instruction is determined according to the read instruction. Is transferred from the first storage means and transferred to the second storage means, and the first transfer means for storing the waveform ID of the transferred waveform data in the third storage means,
In response to the input read instruction, a plurality of waveform data related to the read instruction is read from the second storage means, and a plurality of musical sounds are generated simultaneously based on the read plurality of waveform data Means,
A musical sound generating apparatus characterized in that the transfer of waveform data by the first transfer means and the reading of waveform data by the musical sound generation means can be executed in parallel. The waveform data transfer by the first transfer means and the waveform data read by the tone generation means proceed asynchronously with each other,
2. The musical tone generation apparatus according to claim 1, wherein the first transfer means transfers waveform data by a highly efficient transfer method including block transfer and burst transfer. Prior to the transfer of the waveform data to the second storage means by the first transfer means, it is determined whether or not there is a sufficient free area in the second storage means for storing the waveform data. A second discriminating means;
When the second determination means determines that there is not enough free space, at least one waveform data is erased from the waveform data already stored in the second storage means, and the waveform data is 2. The musical tone according to claim 1, further comprising: an erasing unit that secures a free space necessary for storage and erases the waveform ID of the erased waveform data from the third storage unit. Generator.   The first transfer means transfers a plurality of waveform data in parallel from the first storage means to the second storage means within the limitation of the data transfer speed of the first storage means. The musical tone generation apparatus according to claim 1, wherein: The readout instruction includes speed designation information for designating the readout speed of each waveform data related to the readout instruction,
The musical sound generating means reads the waveform data at a reading speed specified by the corresponding speed specifying information, generates a musical sound,
5. The musical tone generation apparatus according to claim 4, wherein the first transfer means controls the transfer speed for each waveform data to be transferred based on the corresponding speed designation information. The waveform data transfer by the first transfer means and the waveform data read by the tone generation means proceed asynchronously with each other,
The first transfer means is different in parallel from the first storage means to the second storage means in parallel with each other within the limitation due to the data transfer rate of the first storage means. 2. The musical sound generating apparatus according to claim 1, wherein the musical sound generating apparatus can transfer at a speed. Timbre switching instruction means for instructing timbre switching;
When timbre switching is instructed by the timbre switching instruction means, whether the waveform data used preferentially in the instructed timbre is stored in the second storage means is used preferentially. Third determining means for determining based on the waveform ID of the waveform data and the waveform ID stored in the third storage means;
If the waveform data used preferentially is not stored in the second storage means as a result of the determination by the third determination means, the waveform data is read from the first storage means in units of waveform data. 2. The musical tone according to claim 1, further comprising a second transfer unit that stores the waveform ID of the transferred waveform data in the third storage unit in addition to the transfer to the second storage unit. Generator.

Images