JP2901154B2 - Electronic musical instrument - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic musical instrument capable of converting data read from a waveform data storage device in correspondence with a tone generator.

2. Description of the Related Art As an electronic musical instrument, it is well known that data of different waveforms are stored and stored in a storage device in accordance with a timbre and a tone range (pitch), and read out by giving a read address for each tone generator. ing. FIG. 8 shows a block diagram of a conventional electronic musical instrument. In FIG. 8, 1 is a key switch and tone selection switch, 2 is an assignment circuit for the switch,
Denotes an execution control circuit, 4 denotes a waveform data storage device, 5 denotes a bank memory, 6 denotes a frequency number circuit, 7 denotes a frequency number accumulating means, 8 denotes an envelope waveform circuit, 9 denotes a multiplier circuit, and 10 denotes an acoustic circuit.

A key switch and a tone switch 1 are a switch group for selecting a key position played by a player and a selected tone color, and an assignment circuit 2 electrically scans the switch 1 of the switch group to determine whether the switch is open or closed. Information allocated internally. Then, it sends it to the execution control circuit 3 as key information and tone color information. The execution control circuit 3 has a built-in central processing unit, and performs processes such as generating an address for reading waveform data from the waveform data storage device 4 based on the key information and timbre information as described later. The waveform data storage device 4 stores different waveform data corresponding to the timbre and the tone range (pitch) in different places. That is, the waveform data storage device 4 is composed of a plurality of banks (regions), for example, timbres and gamuts (ranges).
Correspond to the bank. Therefore, a bank is designated by the bank memory 5 in order to generate a certain musical tone.
Next, a read address range corresponding to the key information is designated by the frequency number circuit 6 and the frequency number accumulating means 7. The bank memory 5 stores the waveform data in the waveform data storage device 4 according to the address determined by the frequency number circuit 6 and the frequency number accumulating means 7.
Is read. An envelope is added to the read waveform data by the output of the envelope waveform circuit 8 by the multiplication circuit 9, and the acoustic circuit 10 performs digital-to-analog conversion to obtain a tone signal.

[Problems to be Solved by the Invention] The waveform data storage device 4 has the same data format. Therefore, the bit length of the waveform data may be small depending on the desired timbre, and the bit length of the waveform data may be small depending on the timbre. Further, as a format of the waveform data, there are a linear expression, an exponential expression, a difference data expression, and the like. Thus, the waveform data storage device 4
When various types of waveform data are stored together in
When processing is performed by using an envelope waveform after reading from the waveform data storage device 4, in some systems, the waveform cannot be converted because of the circuit device.

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned drawbacks. A waveform data storage device stores waveform data in an optimum format as a timbre and a tone range (pitch), and reads out the data format from the waveform data storage device to change the data format to a tone generator. It is an object of the present invention to provide an electronic musical instrument which can be converted and processed in accordance with the electronic musical instrument.

[Means for Solving the Problems] FIG. 1 is a diagram showing the principle configuration of the present invention. In FIG. 1, 3 is an execution control circuit, 40 is a waveform data storage device,
6 is a frequency number circuit, 7 is frequency number accumulating means, 13
Denotes a state memory, and 15 denotes a data format conversion circuit.

A plurality of tone generators, a keyboard having a plurality of keys and a plurality of tone switches for setting a desired tone, and various tone generators for controlling various tone signals in accordance with the key and tone information obtained by scanning them. An execution control circuit that transmits the frequency information according to the key information, a frequency number circuit that stores a frequency number corresponding to the key information corresponding to each tone generator, and an output value of the frequency number circuit that is accumulated in a time-division manner and the key information is accumulated. Accumulating means for outputting an address according to the key information, reading out the data of the waveform data storage device stored in advance by the address corresponding to the key information, and generating a desired musical tone by the plurality of musical tone generators. In the electronic musical instrument, the address corresponding to the key information is divided into an integer part address and a decimal part address, and the former is transmitted as a read address for the waveform data storage device, and the decimal point position conversion is performed. Path, an address control circuit for converting the output address of the decimal point position conversion circuit into a use address format at a location where the desired waveform data is stored in the waveform data storage device, and an address control circuit for converting the desired waveform data read from the waveform data storage device. A state in which a data format conversion circuit for converting the data format and various control signals corresponding to each tone generator sent from the execution control circuit for controlling the operation of the decimal point position conversion circuit / address control circuit / data format conversion circuit are stored. And a decimal point position conversion circuit according to a control signal output from the state memory.
The operation of the address control circuit / data format conversion circuit is controlled for each tone generator.

[Operation] A large amount of waveform data is stored in advance in the waveform data storage device 40 in FIG. 1, for example, in a format corresponding to a timbre and a tone range (pitch). A frequency number is obtained in the frequency number circuit 6 based on the key information, tone color information, and the like obtained from the execution control circuit 3, and is accumulated by the frequency number accumulating means 7 in order to obtain a predetermined read address range. Next, the waveform data storage device 40 is read based on the output value of the accumulation means 7. The read waveform data is applied to the data format conversion circuit 15. When the waveform data is linear 16 bits or linear
Even if the data format is different, such as when data of 16 bits and data of exponential expression are mixed, the data is converted into data of linear expression, for example. It is preferable to obtain a data format conversion control signal (WFS) from the state memory 13 for each tone generator so that the conversion is performed for each tone generator. Therefore, the configuration of the multiplication circuit for adding an envelope to the output value of the data format conversion circuit 15 is simple and good.

Next, the number of bits of the read address for the waveform data storage device can be easily changed by the decimal point position conversion circuit. Further, even if the memory format used for the waveform data storage device is mixed, such as a dynamic RAM / static RAM, an address corresponding to the memory format can be obtained by the address conversion circuit to easily cope with the problem.

Embodiment FIG. 2 is a diagram showing a specific configuration of the data format conversion circuit 15 shown in FIG. 1 as an embodiment of the present invention. FIG. 2A
, 15-1 indicates a data selector, and 15-2 indicates an inverter. The signal WFS applied to the data selector 15-1 switches between keeping the input data as it is and converting it to converted output data. That is, when WFS = "L", the input data MD15-0 are output data WD15-0.
(The linear 16 bits become the linear 16 bits as they are.) When WFS = “H”, MD15 to MD8 of the waveform data are the original linear 8 bits, and MD7 to 0 are indefinite data. Are output as upper bits as they are in MD15-8, and the bits in lower MD7-0 are MD15 as sign bits, which are all lower bits.

FIG. 2B shows an internal configuration circuit for one bit of the data converter. That is, the circuit can be configured by combining a known AND circuit and an OR circuit.

Next, FIG. 3 shows another circuit example of the data format conversion circuit 15 shown in FIG. In FIG. 3, reference numeral 15-3 denotes a data selector, reference numeral 15-4 denotes an inverter, and reference numeral 15-5 denotes a converter for linear expression. The input data MD15-0 are linear 16-bit data and 16 bits of exponent notation of 12 bits of mantissa and 4 bits of exponent.
When bit data is mixed, “L” and “H” of WFS
, Exponential data of M × 2- ^P is obtained from the output of the data converter 15-3 as unified data.

Next, a converter 15-5 converts the data into a linear expression Y15-
If the data of 0 is expressed as M15-0, the data of M15-0 is converted to the fourth by the value of the exponent part P expressed by Y19-16.
The result is shifted as shown in the figure. That is, data in a linear expression is obtained.

As the signal WFS in the above description, a signal predetermined for each tone generator is stored in the state memory, read, and applied to the data format converter. Alternatively, the storage of the state memory is made to correspond to the timbre or the range (pitch),
It can be read and applied to a data format converter.

FIG. 5 is a block diagram showing the addition of a configuration such as control of an address from which the waveform data storage device is read. In FIG. 5, 5 is a bank memory, 11 is a decimal point position conversion circuit, 12 is an address control circuit, 13 is a state memory, 14 is a frequency number adjustment circuit, 15 is a data format converter, and 40 is a waveform data storage device. .

The bank memory 5 stores a code for designating a bank area corresponding to each tone generator. Therefore, the stored data is read out and the area stored in the waveform data storage device 40 is specified.

The state memory 13 stores an information signal (F) for changing the read size of one bank area in the waveform data storage device 40.
S), an information signal (MS) for changing the number of address bits according to the address format of the memory included in the waveform data storage device, and changing the waveform data according to the format of the waveform data in the same memory as the tone waveform. An information signal (WFS) for performing control for taking in as data is provided corresponding to each tone generator. FIG. 6 shows an example of the configuration of one word of the state memory 13, in which the information signals WFS to FS are 0 to 3
After 4 bits, data for controlling other parts (not shown) is stored. This state memory decodes key information and tone color information sent from the execution control circuit 3 shown as a conventional technique by an address decoder, reads out a word at a predetermined position based on the address, and outputs it. It is also possible to use range information instead of the key information, and make some keys into one group as information.

Next, the frequency number adjusting circuit 14
Is adjusted before the frequency number obtained in the step (1) is supplied to the accumulating means 7. That is, even if the data selector as shown at 15-1 in FIG. 2A is used to change the bit string of the frequency number to the same frequency even if the size of one bank area of the waveform data storage device 40 is changed according to the information FS. Adjust to read the waveform with. The accumulating means 7 is composed of an adder and an accumulating buffer as is well known, accumulates frequency numbers in a time-division manner for each tone generator, and outputs the adder output as an address for reading out the waveform data storage device. Get an integer value and a decimal value (fraction of the accumulation result).

The decimal point position conversion circuit 11 determines which position of the bit string of the output of the accumulation means 7 is a decimal point,
It is determined according to the FS, a bank code is added to a higher order, and then a read address for the waveform data storage device 4 is output. At this time, 15- of FIG.
Use the one shown in 1. For example, one bank is 64k
In the waveform data storage device 40 having a total of 256 banks of words, when FS = "L", it is used as it is.
When FS = “H”, shift by 4 bits and transfer one bank
Control to be 1M words. If the information FS is stored and stored in the state memory 13 in correspondence with the tone generators, it is possible to selectively use waveforms that use a large amount of memory space and waveforms that do not use much for each tone generator.

The address control circuit 12 is a circuit for controlling the read address by the information MS when the memory constituting the waveform data storage device 40 is various such as ROM and D-RAM. Has a configuration like the data selector 15-1 shown in FIG. Dynamic RAM with multiplexed row and column addresses of 64k words and 25
6k words and 2 types, ROM and S
-Information MS when the format is 2 types of RAM and 4 types in total
The memory can be switched and used by the control using the combination of 1, MS0.

FIG. 7 shows the control based on the information FS in time when the number of tone generators is eight. One sample time of the system is the entire time when the tone generators GEN0 to GEN7 are operated at the same time. Each information value of one word shown in FIG. 6 is described in the vertical direction for each tone generator. As described above, each information signal can be set differently for each tone generator, or can be set in the same manner.

[Effect of the Invention] As described above, according to the present invention, when the system generates a musical tone waveform using the waveform data stored in the waveform data storage device, even if the waveform data has a different data format, it is common. Therefore, an improved sound quality can be easily obtained by selecting a data format according to the timbre. Also, since the data format can be controlled for each tone generator, an optimal method can be executed for compressing the waveform data.

Further, no matter what form the memory in the waveform data storage device is, appropriate addressing can be performed. The size of the address space can easily be made to correspond to each tone generator, so that it is practically applicable to a wide range and various types of electronic musical instruments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a principle configuration of the present invention, FIG. 2 is a diagram showing a configuration of a data format conversion circuit as an embodiment of the present invention, and FIG. 3 is another embodiment of the present invention. FIG. 4 is a diagram illustrating a configuration of an example, FIG. 4 is a diagram illustrating data shift to linear expression data, FIG. 5 is a block diagram illustrating a configuration of still another embodiment of the present invention, and FIG. FIG. 7 is a diagram showing word information, FIG. 7 is a diagram showing operation timings of eight tone generators, and FIG. 8 is a block diagram showing a configuration of a conventional electronic musical instrument. 3 Execution control circuit 4, 40 Waveform data storage device 5 Bank memory 6 Frequency number circuit 7 Frequency number accumulating means 11 Decimal point position conversion circuit 12 Address control circuit 13 State memory 14: Frequency number adjustment circuit 15: Data format converter

Claims (1)

(57) [Claims] 1. A plurality of tone generators, a keyboard having a plurality of keys, a plurality of tone switches for setting a desired tone, and various control signals corresponding to key / tone information obtained by scanning the keys. An execution control circuit for transmitting the frequency number corresponding to each tone generator, a frequency number circuit for storing a frequency number corresponding to the key information corresponding to each tone generator, and an output value of the frequency number circuit in time division Accumulating means for accumulating and outputting an address corresponding to the key information, reading out the data of the waveform data storage device stored in advance by the address corresponding to the key information, and In an electronic musical instrument for generating a desired musical tone, an address corresponding to the key information is divided into an integer part address and a decimal part address, and the former is transmitted as a read address for a waveform data storage device. A several-point position conversion circuit; an address control circuit for converting an output address of the decimal point position conversion circuit into a use address format where a desired waveform data is stored in the waveform data storage device; A data format conversion circuit for converting the data format of the desired waveform data; and various controls corresponding to each tone generator sent from the execution control circuit for controlling the operation of the decimal point position conversion circuit / address control circuit / data format conversion circuit A state memory for storing signals, wherein the operation of the decimal point position conversion circuit / address control circuit / data format conversion circuit is controlled for each tone generator in accordance with a control signal output from the state memory. An electronic musical instrument characterized by that: