JPH03205906A - Signal generator - Google Patents

Abstract

PURPOSE:To easily change the stored arbitrary waveform data by storing the repeated waveform of an arbitrary input signal in a storage device with use of a pulse corresponding to a fundamental period of an input signal. CONSTITUTION:When a signal of a repeated period t2-t1 is inputted to a pitch extracting circuit 2, a pulse train (b) of a repeated frequency fp(t2-t1=l/fp) is outputted, and an M multiplier 3 outputs a pulse train (c) of a frequency M.fp. When a start pulse (d) is supplied to a trigger input terminal 8 at the time t0, a controller 9 synchronized with a pulse at the time t1 of the pulse train (b), and outputs a pulse train (e) and (f) of the frequency M.fp only for a period of t1 to t2. An input signal (a) is sampled by the sampling of the pulse train (e) in an A/D converter 10, and outputted. A digital signal is written in a storage device 5 by synchronizing with the write pulse of a pulse train (f). In such a way, a separate writing device is not required, and an arbitrary stored waveform can be changed simply.

Description

Detailed Description of the Invention [Industrial Field of Application J] The present invention stores an input waveform according to the fundamental period of an input signal, and also stores the input waveform according to the fundamental period of another input signal. The present invention relates to a signal generating device that enables readout.

[Prior art 1] As shown in FIG. 1, a conventional signal generator includes a pitch extraction circuit 2 that outputs a pulse train for each basic period of an input signal;
An M multiplier 3 that multiplies the frequency of the clock output pulse by M, a counter 4 that counts the pulse train multiplied by M, a clock II@box 5 that inputs the counter output as an address, and a clock storage device 5. It consists of a D/A converter 6 that takes out the read digital signal as an analog signal.

Note that 1 is an input terminal and 7 is an output terminal.

Next, its operation will be explained. First, when a signal with a certain repetition period is input to the input terminal 1, the S repetition frequency f is determined by the pitch extraction circuit M2. A pulse train is output. Further, the pulse train is input to an M multiplier 3, and the p pulse train of frequency M-f is counted by a counter 4. Since this count value is used as the address of the next stage tlHl5, if arbitrary waveform data expressing one period in M words is written in the storage device 5, each time a pulse of Mu is input to the counter 4. When the waveform of one cycle is output from the I unit If5, that is, when the pulse train M-rp is input to the counter 4, ! The stored waveform f, which is output by the device 1f5, is outputted at a repetition frequency of p. Further, the digital signal outputted at the repetition period fp was outputted as an analog signal by the D/A converter 6.

[Problem to be solved by the invention Rl However, the conventional signal generator HIf can only output waveform data that has been stored in advance, and a separate writing device is required when changing the waveform data. Therefore, it was not possible to easily change the stored waveform data.

Furthermore, Japanese Patent Application Laid-Open No. 52-33515@ describes a device that adjusts musical tones in real time by sequentially reading out musical tone signals stored in a storage device, and changes the tone color and tone quality over time. There is.

However, in such a vRH, since the musical tone is synthesized by changing the waveform one after another from the initial waveform to the final waveform, any <analog> input signal is stored in the storage device, and other <analog> input signals are This cannot be read out accordingly.

SUMMARY OF THE INVENTION In view of the conventional problems, an object of the present invention is to provide a signal generating device that can easily change arbitrary waveform data stored in a very simple manner.

Means for Solving raa The signal generating device of the present invention, which has been made to solve the above problems, comprises: pitch extraction means that outputs a pulse according to the fundamental period of an input signal; a multiplier for multiplying the frequency of the pulse train; a counter for converting the multiplied pulse train into an address signal; and a counter for outputting a control signal based on the output pulses of the pitch extraction means and the output pulse train of the multiplier. control means;
analog-to-digital conversion means for converting the input signal into a digital signal according to the control signal; storage means for storing the digital signal and from which the digital signal is read according to the address signal; and a digital signal read from the storage means. It consists of digital-to-analog conversion means for converting into analog signals.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 2, the pitch extraction circuit 2, the M multiplier 3, the counter 4, the memory 8W15, and the D/A converter 6 have the same functions as those of the prior art. Further, 8 is an input terminal to which a trigger that gives the timing to write the input signal to the storage device W5 is input, 10 is an A/D converter for converting the input analog signal into a digital signal, and 9 is the note @!
W15, and A/D] Nha-9 1 0 wo Hm
trutame I) HJfmHrllC-Yes.

Next, we will explain the operation. t as shown in Figure 3a.
When a signal with a repetition rate of 2 t 1 is input to the pitch extraction circuit 2, the repetition frequency f, (tzt1=1/fI
)) is output, and further pulse train b
The frequency is multiplied by M by the M multiplier 3, and a pulse train having a frequency M-fp like waveform C is output. The pulse train C is input to the counter 4, and each time a pulse is added, the address of the memory device W5 is incremented. Thereafter, signals are output by the conventional and @-like operations. Here, record the waveform data. Device 5
This section explains the operation for automatically writing to . The pulse trains b1 and C are controlled by IIl'I! The start pulse d is input to the R position 9 at time t. When applied to the trigger input terminal 8 at , pulse trains e1 and f having a frequency M-f are output for a period from t1 to t2 in synchronization with the pulse at time t1 of pulse train b. Here, the input signal a is input to the A/D converter 10, and the input signal a is sampled by the sampling pulse of the pulse train e and output as a digital signal. Furthermore, the digital signal is a memory device! '5, and writing is performed in synchronization with the concussion pulse of the pulse train f.

In the above embodiment, the pulse train e is used as the sampling pulse for sampling the input signal, but the pulse train C may also be used. In addition, in the above embodiment, one of the input signals
Write down the waveform of the period! We have shown the case of writing to the device, but 2
Even if the waveform is longer than the period, the same effect as in the above embodiment can be achieved.

[Effects] As described above, the present invention stores the repetitive waveform of an arbitrary input signal in a storage device using pulses corresponding to the fundamental period of the input signal, so it is easy to write arbitrary signals without the need for a separate writing device. can be changed to the stored waveform.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional signal generating device, FIG. 2 is a diagram showing a signal generating device according to the present invention, and FIG. 3 is a diagram showing waveforms of various parts in FIG. 1...Signal input terminal 3...M multiplier 5...Note I! @ Place 6...D/A converter 7...Signal output terminal 9...Control a device 10...D/A converter 2...・Pitch extraction circuit 4...Counter 8...Trigger input terminal

Claims (1)

[Scope of Claims] Pitch extracting means for outputting pulses according to the fundamental period of an input signal; multiplying means for multiplying the frequency of the pulse train output from the pitch extracting means; and converting the multiplied pulse train into an address signal. a counter for converting, a control means for outputting a control signal based on the output pulse of the pitch extraction means and an output pulse train of the multiplication means, and an analog-to-digital conversion means for converting the input signal into a digital signal using the control signal. A signal generating device comprising: storage means for storing the digital signal and reading out the digital signal according to the address signal; and digital-to-analog conversion means for converting the digital signal read from the storage means into an analog signal.