JPH0443398A - sound effect adding device - Google Patents

Abstract

PURPOSE:To prevent a noise from being generated owing to other arithmetic processing during the output of an additional sound by storing data for decision making in an output register and performing interpolation arithmetic based upon data before and behind the data for decision making when other arithmetic processing is performed. CONSTITUTION:A control program memory 6 is stored with plural control programs for generating an effect sound selected by an effect sound selecting circuit 3 and a control program corresponding to the effect sound is selected by the effect sound selecting circuit 3 and outputted. Then when the effect sound adding device performs the process for other equipment, the data for decision making is stored in the output register and the process is carried out according to the data before and behind the stored data for decision making to interpolate absent data for additional sound generation. Consequently, even when an another program which is large in process quantity is executed during the musical sound generation, the effect sound adding device generates no noise.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a digital signal processor (hereinafter referred to as
The present invention relates to a sound effect adding device that adds desired sound effects to musical sounds generated from an electronic musical instrument or the like using a DS processor (abbreviated as DS processor).

(Prior Art) Conventionally, there has been a sound effect adding device that adds sound effects such as reverberation to the output of an electronic musical instrument or the like.

Such sound effect adding devices are provided with a plurality of programs corresponding to various independent sound effects, and therefore have the disadvantage that the scale becomes large when selecting and adding sound effects from among the plurality of sound effects. With the recent development of DS/processors, it has become possible to construct a small-scale sound effect adding device by synthesizing and controlling a plurality of sound effects using a program.

(Problems to be Solved by the Invention) However, such an S processor does not require the above-mentioned
The sound effect adding device not only performs digital arithmetic processing on musical sound signals, but also performs various arithmetic processing, controls external equipment, and communicates with a microcomputer. However, when fishing on a boat, the sound effect adding device described above must perform other processing such as other large calculations or control at the same time while playing musical tones with added sound effects, in other words, while performing calculations on musical sound signals. Never.

The reason for this is that the DS/processor normally repeats the execution of one cycle of instructions in one sampling period, so if another instruction with a large amount of processing is executed in the meantime, the instruction cycle will exceed the sampling period, resulting in no effect. I didn't pronounce it properly.

This is because noise may be generated. In that case, usually
- After temporarily muting the sound and canceling the arithmetic processing of the musical tone signal, performing the above separate processing, and then repeating the above again.

Performs arithmetic processing on musical tone signals. However, it is extremely unnatural to temporarily mute the sound during pronunciation.

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a sound effect adding device that does not generate noise even when other processing is performed while maintaining a natural sounding state.

(Means for Solving the Problems) The present invention achieves the above object by providing a sound effect adding device with an output register for storing a plurality of arithmetic processing results of a musical sound signal, so that the sound effect adding device can be used for other devices. When performing processing, data for discrimination is stored in the above output register, and additional sound formation data that is missing due to the above and other processing is interpolated from data before and after the stored discrimination data. Achieve with configuration.

(Function) According to the first aspect of the present invention, a sound effect adding device that does not generate noise even if another program with a large processing amount is executed while musical sounds are being generated is realized.

(Example) Hereinafter, the present invention will be explained using the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
1 is a musical tone signal generation circuit, 2 is an A/D converter, 3 is a sound effect selection circuit, 4 is a sampling clock generation circuit, and 5 is a D
S. processor, 6 a control program memory, 7 a data memory, 8 a D/A converter, 9. lO is an LPF (low pass filter).

The musical tone signal generation circuit 1 is a circuit that generates a musical tone signal corresponding to keyboard information etc. in an electronic musical instrument, etc., and its output is an A/D
In the converter 2, the signal is sampled by the sampling clock supplied from the sampling clock generation circuit 4, converted into digital data, and serially outputted to the DS/processor 5. The sound effect selection circuit 3 is a circuit for selecting a desired sound effect to be added to a musical sound signal, and includes a sound effect designation switch circuit for specifying the sound effect, parameters regarding the sound effect, delay time, and calculation coefficients. It is composed of a data forming circuit that forms parameter data, and the formed data is supplied to the DS processor 5.

The sampling clock generation circuit 4 includes A/D converters 2 and D.
The signal is supplied to the S-processor 5 and the D/A converter 8 and synchronized with each other.

The digital musical tone signal is processed and output to the DS processor 5. The digital musical tone signal inputted from the A/D converter 2 is written into and read out from the data memory 7 based on the data inputted from the sound effect selection circuit 3 and according to the control program outputted from the control program memory 6. and calculations to form a digital musical tone signal to which desired sound effects have been added, and output it to the D/A converter 8. Further, the DS processor 5 executes one cycle of the program outputted from the control program memory 6 in one sampling period generated by the sampling clock generation circuit 4.

The control program memory 6 stores a plurality of control programs for forming the sound effects selected by the sound effect selection circuit 3, and outputs the control programs corresponding to the sound effects selected by the sound effect selection circuit 3. do. The data memory 7 is controlled by the DS processor 5, and data is written and read according to the control program described above. The D/A converter 8 converts the digital musical tone signal input from the DS processor 5 into one of the sampling clocks generated by the sampling clock generation circuit 4.
At the timing of /2, the signals are divided into Rch and Lch channels, converted into analog signals, and outputted to LPFs 9 and 10, and respective predetermined high frequencies are cassetted and outputted. The DS processor 5 also includes an input/output port for external device control signals for controlling external devices.

FIG. 2 is a flowchart explaining the operation of FIG. 1. Detects the falling edge of the clock pulse of the sampling clock generation circuit 4 and starts the control program (
Step 1 (hereinafter abbreviated as Sl). After one cycle is completed, it waits until the falling edge of the next clock pulse.

The musical tone data of Rch and Lcth after adding the sound effects of the previous cycle is read from the output register and output to the D/A converter 8 (S2), and the digital musical tone signal from the A/D converter 2 is input to the input register. (not shown) or written into the data memory 7 (S3).

The delay data and calculation coefficient data corresponding to the sound effect selected by the sound effect selection circuit 3 are compared with those in the previous cycle to determine whether there is a change (S4), and if there is a change, the sound effect is changed to a mode change routine. Branches to step S5), and if there is no change, the main routine determines whether to perform arithmetic processing on the musical tone signal or control external equipment (
56), when processing as the main routine, the sound effect selected by the sound effect selection circuit 3 is added to the digital musical tone signal applied to the input register by performing a predetermined calculation. If so, a control signal for controlling the external device is generated (S8). Note that the external device may be a display LED, a microcomputer, or the like.

The data to be calculated by the main routine in S7 is
If the calculation cannot be performed due to external device calculation, data is formed by interpolation calculation based on the output data of the cycles before and after the calculation could not be performed (S9). 87. The data calculated and formed in S9 is stored in the output register (S
10), one cycle of the program ends here, and Sl
Return to (Sll).

FIG. 3 shows the data state for each cycle of the output register (S10) in which data for performing the interpolation calculation of FIG. 2 89 is stored.

In Figure (a), address 110 is the value output by the current calculation, address 111 is the previous value, and address 112 is the value from the previous time. Also, address 111
The value of is used as the musical sound signal after adding sound effects.

It is output to the D/A converter.

First, in the first cycle, the value 3 calculated at address 110
333 is stored and the previously calculated value 2 of address 111 is stored.
Outputs 222. In the second cycle, the values stored at each address are moved, and the calculated new value 4444 is stored at address 110, and the previous value 3333 is stored at address 110.
Output. The third cycle is similarly output.

Figure (b) shows the output register (s) during the interpolation routine (S9).
io), and if the routine branches to another routine (S8), the result of the operation in the main routine (S7) cannot be obtained, so the determination data 8000 is stored at address 110 of the output register. Further, the address 111 stores the previous calculation value, and the address 112 stores the calculation value of the previous calculation, respectively, and the calculation value of the address 111 is output. In the second cycle, the calculated value is similarly stored at address 110 and the value at address 111 is output. However, since 5ooo is stored as discrimination data at address 111, instead of outputting it as is, interpolation is performed using the values at addresses 112 and 110 to output an interpolated value of 3333, and the interpolated value is stored as is at address 111. .

Figure (C) is a redrawn version of Figure 1 (b) to make it easier to understand, and shows the state of the second cycle. B represents the previous calculation value, ie, the value at address 112, and B' represents the current calculation value, ie, the value at address 110.

Since address 111 was discrimination data 8000, B
-B' is interpolated to obtain the value of A. At the same time, it is stored in address 111 of the output register and D/
It is output to the A converter 8.

As described in detail above, by performing interpolation between two points, even if another routine S8 is executed, it is possible to approximate the value that could not be calculated in the main routine of S7. However, 1. Normally, musical tone signals have many curve-like changes, and interpolation between the two points described above is not sufficient. In that case, changing the number of output registers of the 510 from three to five, for example, will produce a more beautiful result. It is possible to make approximations.

Note that in the above-described present invention, the output of the signal after the arithmetic processing is delayed by one sampling pulse, but this does not pose a practical problem. For example, suppose the sampling clock is 20kHz.

This is because one sampling time is 50 μsec, and the human auditory sense of delay is 2 to 3 msec, which is not a problem.

(Effect of the invention) As will be clear from the above detailed description, the present invention is advantageous.

It has an output register that can store a plurality of arithmetic processing results of musical tone signals, and when performing other arithmetic processing, discrimination data is stored in the output register, and data before and after the discrimination data stored in the output register is used. This device is designed to perform interpolation calculations, and is a musical sound effect adding device that does not generate noise even if other calculation processing is performed during output of additional sound and the processing is missed, so there are benefits to using it. .

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, the second part is a flowchart showing the operation of FIG. 1, and FIG. 3 is a diagram explaining the interpolation operation of the register, which is the main part of the present invention. 1...Musical sound signal generation circuit, 2...A/D converter, 3...Sound effect selection circuit, 4...Sampling clock generation circuit, 5...Digital signal processor (DS processor) ), 6...control program memory, 7...data memory. Patent applicant: Matsushita Electric Industrial Co., Ltd. Agent: Hisashi Hoshino. , p Figure 2

Claims (1)

[Claims] A musical sound output means for digitally outputting the musical sound of an electronic musical instrument, a sound effect adding means for adding a sound effect to the output, and a sound effect selection means for selecting one of a plurality of sound effects, The sound adding means includes a control program memory having a plurality of control programs corresponding to selected sound effects, a plurality of data memories, and a data memory control for writing, reading, and addressing the data memory in accordance with the control program. In addition to outputting a signal,
A sound effect adding device characterized by having a digital signal processor constituted by a calculation means for performing calculations based on the control program described above.