JPS59107389A - Tone varying apparatus for electronic musical instrument - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a device that instructs an electronic musical instrument to change the wave j[3 at an arbitrary time, and changes the tone color by this waveform change.

Background Technique 1 (,i) Conventionally, tones of electronic musical instruments have been changed by adding multiple single tones to the electronic ones and outputting them, or by adding a waveform of light containing 8 harmonics, as in a music synthesizer. Using several vibrators, each mouth waveform is passed through a plurality of filters whose frequency characteristics can be changed to increase or decrease the harmonics contained in the output waveform of the filter.

In addition, one basic sine wave is stored in a digital memory, and when the bee ejects the bladder, it is stored in the digital memory, and the tone is changed by modulating the basic sine wave. is also being carried out.

However, the method of adding multiple single tones requires a large number of oscillators, and the level of each sine wave may be changed in order to change the timbre, so a circuit for this must be provided. First, the equipment was large.

On the other hand, the method of increasing/decreasing harmonics using filters also required a large number of optical oscillators and filters, making the entire device large.

Furthermore, the method of digitally storing or modulating a fundamental sine wave poses a problem in the transverse speed of the device, which also requires large hardware.

For example, if the output of this method is expressed mathematically, Y-[5ill(ωt +l'sin l(ω[)...) where ω is the fundamental frequency.
・・・・It becomes ■, which changes ■ and 1ku,
Since the actual device handles time-discrete data, Y 11 − Hi sin (ωn △
l−1y s 1nKzy+ ω n△Ln・
...■ However, I+ =0.1.2,3. It can be expressed as... Here, 8t is the difference between tlI between the 1st of n and 1F1, but it may also be the period of the tarok during calculation. Furthermore, although E is generally a function of time, in this case it would not depart from the gist of the explanation even if it were assumed to be a constant.

■The formula is a formula with many east lines, as is obvious from a child's perspective. In digital calculations, multiplication and division are much more time-consuming than addition and subtraction (this takes a long time, so the calculation of the formula (■) takes a long time.Moreover, the calculation must be completed within a time well below Δ℃. Therefore, Δt cannot be made shorter than S, and there is a limit due to the amount of data that can be incorporated into calculations.Therefore, this method does not cause timbre changes unless calculations are performed at high speed. This means that 80% of data cannot be utilized in 1 minute.

DISCLOSURE OF THE INVENTION The purpose of the present invention is to solve the problems of the traditional technique Ki as described above, and to switch from a single waveform being read out from Memo 96 to the reading of the waveform of a song by command. An object of the present invention is to provide a timbre changing device for an electronic musical instrument that changes the timbre by changing the timbre.

In order to accomplish this objective), the Pi device of the present invention includes a memory that stores waveform data and waveform change data, an address generation circuit that can send an address input to this memory, and a value of the address input that is converted into waveform change data. A central processing unit may be provided that issues a command to change the output waveform from the memory when the two match.

Since the present invention is configured as shown above, the output waveform can be varied in a variety of ways with a simple device. It has also become possible to reduce the size of electronic musical instrument equipment.

Best mode for carrying out the invention Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 shows the configuration of an embodiment of the color changing device of the present invention, in which 1 is a central processing unit (hereinafter referred to as FCl-'U), and 2 is a memory in which waveform data is stored. (hereinafter referred to as memory M1), 3 is an address generation circuit that generates the lower address of memory M1, and 4 is a memory in which the execution program of this device and waveform change point data are stored (hereinafter referred to as memory M2). , 5 is an expansion board that connects the CPU I and peripheral elements, 6 is an input/output coincidence detection circuit that compares the address generation circuit and waveform change point data, and outputs a match signal if they match, and 7 is a memory. This is a D/Δ transformer that converts the digital waveform data output from M1 into analog. In addition, φ is a clock signal, Ao of memory MI
``At is the lower address designation input, 〇 and above are the upper address designation inputs, [)o to D7 of the memory M1 are the waveform output data, and the CPU 1 paste.

~D7 is waveform change point data and upper address data of Ml. Furthermore, RD is a signal that instructs the memory to read,
WR is a signal for instructing writing, RESET is a signal for resetting the address redundancy circuit 3, and C0UT is a signal for transmitting the A-barflow of the lower address to the CPU 1.

The operation will be explained below.

Here, waveform data representing a specific waveform such as a square wave or a triangular wave is stored in advance in the memory M+, and an execution program and one period of the specific waveform are stored in the memory M2 at what point and in what order. It is assumed that waveform change point data that has been preliminarily set has already been stored.

First, the CPU 1 specifies the upper address of the memory M1 via the expansion baud 1-5, thereby specifying the waveform to be read out first. Next, the waveform change point data is taken out from the memory M2 and inputted to one input of the input coincidence detection circuit 6 (using an integrated circuit 74LS85, for example) via the expansion board 5. Since the waveform to be read and the changing point of the waveform have been determined, when the reset l~ of the address generation circuit 3 is released, the address generation circuit 3 changes the clock φ to the clock 1~.
Then, the lower addresses of the memory M1 are outputted, and starting from the lowest address of the previously determined waveform, the waveforms specified earlier are read out in increasing order of the lower addresses. Since the output of the address generation circuit 3 is the other input of the input coincidence detection circuit 6, as the lower address increases as reading progresses, it will eventually match the waveform change point data.

Then, the CPU 1 detects this via the expansion board 5,
Change the upper address of memory M1. When the upper address is changed, reading jumps from the originally selected waveform to another waveform, and reading of the new waveform continues as the lower address increases. In this way, when the output of the address generation circuit 3 reaches the maximum lower address (C), the address generation circuit overflows and all bits of the output become zero,
Output C01JT. Here CPLJI is C0IJT
If this is detected, the upper address is returned to the state before the change, and the waveform change point data is left as it was at the beginning, the exact same read operation will be performed and the same waveform as the beginning will be output from memory M1.
Ru.

Figure 2 shows a waveform diagram explaining the above read operation.1°Addressing is performed using 10 bits 1~, so Ao''-△7 is the lower address designation input, 88~A9 is the upper address designation input. Addressing will be the human power.Pa.

Pl...P765 indicates each address of the memory M1 where waveform data is stored. Waveform selection by upper address specification is as follows ←X (-r Now.

Initially, since the address generation circuit 3 is being reset, Ao=A7 is all zero. Here, if we take 80 mira 1, AO to A9 is 0100oooooo, which is expressed in binary, so if we change it to decimal, it is 256.
Therefore, P2SG, that is, the first address of the waveform ■ has been designated.

If As and A9 are both zero, Ao”A9 is oooo.

Since the decimal representation of oooooo is zero, it means that Pa, that is, the first address of the corrugator, has been specified.

After selecting the waveform, the reset of the address generation circuit 3 is released, and each time one clock ψ is input, Ao-AV increases by 1, and P25G, P2S5, etc.
The reading is performed in the order of . . . , and waveform output data Do to 07 are output from the memory M1. One of the two human inputs of the human force coincidence detection circuit 6 contains waveform change point data (currently 51
] is set to cell 1 before reading starts, and the other input is input to specify the lower file ζless.
Since the lower address designation signal increases and reaches 110011 in binary notation, it matches the waveform change point data, and the input match detection circuit 6 outputs a match signal. CI) tJ1 detects this through the expansion port 5 and changes 0 to A9 to the upper addressing input, so the read jumps from one waveform to another. o i to jump from waveform ■ to waveform ■
o o '+ '+ o o i i to 000011
0011 and 7, and jump from waveform 1 to waveform H (reverse change from side to side).

Figure 913 shows a jump from waveform J to waveform ■ with the waveform change point data set to 51. JjG], the same waveform is repeated.

In this embodiment, 74 and 885 are used for the input coincidence detection circuit, but this part can be processed by the CPtJ 1 program.

As explained above, in the timbre changing device of the present invention, when the lower address of the memory M1 matches the waveform change point data, the upper address is changed, the waveform being read is jittered to another waveform, and the output waveform is changed. do. As the waveform changes, the harmonic components included in the waveform fluctuate, resulting in a change in tone. In addition, since the waveform change point data can be changed by simply changing the numerical value set in the input coincidence detection circuit 6, processing can be performed within an extremely short FR, making it suitable for program control.

Furthermore, by using multiple tone color changing devices in parallel, the conventional real Jli! Even difficult tones can now be easily achieved, and the number of circuits in the device can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a 1J block diagram showing an embodiment of the timbre changing device of an electronic musical instrument according to the present invention, FIG. 2 is a diagram showing an example of the correspondence between waveforms stored in the memory M+ and their addresses, and FIG. FIG. 3 is an output waveform diagram from the D/A converter 7 according to the embodiment of the present invention. 1...Memory, 3...Address generation circuit, 4...Memory, 5... - To expansion board 1, 6...Person car i'2 detection circuit. l...o, /A converter, Au~/\3...address designation input, Do~I
J? ...Waveform output data, RD...
Readout No. 18, W) (...Inclusion f3. Applicant: ShinNippon Electric Co., Ltd. Agent, Patent Attorney: Takeo Masuda

Claims (1)

[Claims] 1. Store the digitized waveform data and the waveform change point data that indicates the timing of the waveform change during reading of this molding. - Address generation circuit that provides address input for
1 = Tone change device of an electronic musical instrument, comprising a central arithmetic processing unit for reading and instructing waveform change.