JPH0260199B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a tuning device, and more particularly to improved display of pitch deviation of a signal to be tuned with respect to a reference pitch.

[Conventional technology]

Pitch deviations in tuning devices can be displayed by mechanically swinging the pointer like a pendulum (Utility Model Application No. 59-20297), or by arranging multiple display segments made of light emitting diodes, etc. There is a method (Utility Model Application No. 13591/1983) of lighting a specific segment corresponding to the pitch deviation.

[Problem that the invention seeks to solve]

The former type is mechanical, so it is expensive, and it is also susceptible to vibration and tends to cause distortion, so it requires adjustment. Although the latter is not affected by mechanical vibration and is accurate,
In the conventional display circuit configuration, the pitch deviation measurement result is directly decoded by a decoder and the corresponding display segment is lit, so as the pitch deviation measurement result fluctuates, the lighting segment jumps over the adjacent segment and changes rapidly. , Furthermore, the speed of change is so fast that it is very difficult to see.
There was a problem.

This invention was made in view of the above points,
It is an object of the present invention to provide a tuning device that achieves cost reduction and accuracy by adopting a method of selectively controlling the lighting of a plurality of display segments, and that also prevents the lighting segments from changing rapidly and provides an easy-to-read display. That is.

[Means for solving problems]

The basic configuration of the present invention will be explained with reference to FIG. display the pitch deviation of the signal). This pitch deviation display is performed by setting the segments 1a to 1n corresponding to the size of the pitch deviation to an indicated state. The indicated state is segment 1
When a to 1n are composed of light emitting elements such as light emitting diodes, they are in a light emitting or lighting state,
In the case of other elements, this refers to the corresponding display-on state. The segment specifying means 2 is for specifying a segment that is in an instruction state among the plurality of segments 1a to 1n, and is a means for supplying a signal to put a segment in an instruction state (display on) or in an instruction state. Either means for detecting segments or means for storing information indicating segments in an indicated state may be used.

The measuring means 3 inputs the signal to be tuned,
Measure the frequency or period of this input signal. The measurement result by the measuring means 3 and the output of the segment specifying means 2 are input to the determining means 4, and the determining means 4 determines whether the pitch deviation of the input signal with respect to the reference pitch corresponds to the segment currently in the indicated state. It is determined whether or not. When the determining means 4 determines that the pitch deviation does not correspond to the segment currently in the indicated state, the switching means 5 switches the segment to be next in the indicated state to a segment adjacent to the segment currently in the indicated state. This switching is sequentially performed for adjacent segments until the segment corresponding to the pitch shift is in the indicated state.

[Effect]

When the determining means 4 determines that the pitch deviation of the input signal does not correspond to the segment currently in the indicated state, the switching means 5 does not immediately change the segment corresponding to the pitch deviation to the indicated state, but changes the segment to the currently indicated state. The segment adjacent to the segment located at is sequentially switched to the indicated state. Therefore,
The segments that are in the indicated state are switched and moved in order like the wobbling of a needle, making it easier to see.

As an embodiment, when the determining means 4 determines that the pitch deviation does not correspond to the segment currently in the indicated state, the switching means 5 sets a predetermined response delay, and then switches to the next indicated state. Switch the segment that should become the next segment to the adjacent segment. More preferably, during the period from when the determining means 4 first determines that the pitch deviation does not correspond to the segment currently in the indication state until the segment corresponding to the pitch deviation becomes the indication state. , the response delay when first switching a segment to be in the instruction state to an adjacent segment is set to be larger than the response delay during subsequent segment switching.
In this way, like the vibration of a mechanical pointer,
In the process of movement of a segment in the indicated state, the response is somewhat slow at the beginning of the movement, but the response becomes faster after the segment starts moving. Therefore, it is possible to provide a display that is even easier to see.

In a preferred embodiment, the delay time is not a fixed time, but is set based on a count value using a counting means that adds or subtracts the number of times the judgment result of the judgment means 4 has been confirmed.

〔Example〕

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

FIG. 2 shows the hardware configuration of an electronic musical instrument incorporating the functions of the tuning device according to the present invention.

The key switch circuit 10 includes key switches corresponding to each key of the keyboard KB. The timbre and other operator circuit 11 selects and controls timbre and other musical tone elements.
It includes a plurality of operators for setting and controlling, and also includes display means corresponding to each operator as necessary. The microcomputer 12 is for controlling the operation of this electronic musical instrument, and can be roughly divided into two types: it scans each key switch of the key switch circuit 10 to detect a pressed key, and selects the sound of the pressed key from one of a plurality of musical sound generation channels. , a function to scan the timbre and other operator circuit 11 to detect selection, setting, and control contents of timbre and other musical sound elements, and a tuning function. The musical tone forming circuit 13 is capable of independently forming musical tone signals through a plurality of musical tone generation channels, and is provided with pitch information of pressed keys assigned to each channel under the control of the microcomputer 12. At the same time, control information on timbre and other musical tone elements is given, and a musical tone signal is formed based on this information. The musical tone signal formed by the musical tone forming circuit 13 is given to a sound system 14 and is generated. The general musical tone generation function of such an electronic musical instrument is generally known and may be realized using any configuration, so its details will not be specifically explained.

A plurality of display segments 1a to 1n provided corresponding to the size of pitch deviation with respect to the reference pitch.
For example, a light emitting diode (hereinafter referred to as LED)
Consists of. Specifically, each of these segments 1a to 1n corresponds to a predetermined pitch deviation width. An example of the boundary value of each pitch deviation width is shown in Figure 2, -40 to -30 cents, -30 to -20 cents,
cents, -20 to -10 cents, -10 to -3 cents, -
3 to -1 cent, -1 to +1 cent, +1 to +3 cent, +3 to +10 cent, +10 to +20 cent, +20
11 segments 1a to 1 corresponding to 11 different pitch deviation widths of ~+30 cents, +30 to +40 cents
n is provided. In addition, in the microcomputer 12, -80 to -40 cents and +40 to +
Although determination processing is also performed regarding the pitch deviation width of 80 cents, a display segment corresponding to this pitch deviation width is not provided. The reason why the pitch shift width for performing the determination process is expanded will be described later.

The microcomputer 12 has functions corresponding to the segment specifying means 2, determining means 4, and switching means 5 shown in FIG. 1, and provides the display control circuit 15 with information indicating segments to be lit. The display control circuit 15 performs control to light up segments instructed by the microcomputer 12.

The reference pitch can be arbitrarily specified by pressing a desired key on the keyboard KB. At this time, the musical tone of the pressed key is produced in the same way as a normal electronic musical instrument, and the pitch specified as the reference pitch can be confirmed by ear. In this case, the musical tone forming circuit 13
Since the musical tone of the reference pitch is formed according to the tone selected by the timbre and other operator circuit 11, if the tone corresponding to the instrument to be tuned is selected by the circuit 11, the musical tone corresponding to the instrument to be tuned will be changed. It is possible to produce a musical tone at a reference pitch with the same or similar timbre, and it is not only easy to hear when compared with the musical tone to be tuned, but also suitable for auditory education for tuning. Further, this reference pitch can be specified using any octave key range on the keyboard KB, regardless of the octave of the input signal to be tuned. for that,
When comparing and judging the reference pitch and the pitch of the input signal, the octave of the input signal is automatically determined,
The octaves of the two are automatically matched before a comparative judgment is made. Therefore, when performing a key press operation to designate a reference pitch, it is convenient because only the note name of the musical note to be tuned needs to be considered, and the octave thereof need not be considered.

The measuring circuit 16 corresponds to the measuring means 3 described above, and is connected to the microcomputer 12 via an interface 17. Measurement circuit 1
6, a musical tone to be tuned is input from the outside in the form of an electric signal or a sound wave signal via the input terminal 18 or the built-in microphone 19. The switch 20 selects whether to accept the input signal as an electrical signal or a sound wave signal. The input signal is band pass filter 2
1 and the low-pass filter 22 in parallel,
A selector 23 selects one output of both filters 21 and 22. A response control signal LOW for controlling the frequency response of this measuring circuit 16 is applied to the selection control input of the selector 23 .

Response control signal LOW is microcomputer 1
2 via the interface 17, and depending on the fundamental frequency band of the input signal to be tuned, it is "0" if it is in the high range, and "1" if it is in the low range. This response control signal
By controlling the frequency response of the measuring circuit 16 using LOW, the measuring circuit 1
It is possible to switch to one suitable for the response of No. 6 and its frequency band, and the measurement accuracy can be improved.

The selector 23 selects the output of the low-pass filter 22 when the response control signal LOW is "1", and selects the output of the low-pass filter 22 when the response control signal LOW is "0".
In this case, the output of the bandpass filter 21 is selected. These filters 21 and 22 are for removing noise and harmonic components contained in the input signal.

The output of the selector 23 is input to a positive peak hold circuit 24 and a negative peak hold circuit 25.
Furthermore, it is input to a positive side comparator 26 and a negative side comparator 27. The positive side peak hold circuit 24 is the selector 23
The negative peak hold circuit 25 holds the negative peak value of the output signal. The positive side comparator 26 inputs the positive peak value held by the positive side peak hold circuit 24, and switches the comparison output to an active level when the output signal of the selector 23 is a positive peak value. The negative side comparator 27 inputs the negative peak value held by the negative side peak hold circuit 25, and switches the comparison output to an active level when the output signal of the selector 23 is a negative peak value.

The output of each comparator 26, 27 is applied to the set input S and reset input R of flip-flop 28 to set or reset when at an active level. Therefore, the flip-flop 28 is set at the positive peak point of the output signal of the selector 23, that is, the signal to be tuned, and reset at the negative peak point. In this way, a square wave signal synchronized with the fundamental period of the signal to be tuned is output from the flip-flop 28.

The output of flip-flop 28 is input to a phase lock loop (PLL) circuit 29. The PLL circuit 29 absorbs minute periodic fluctuations of the input signal,
Outputs a square wave signal synchronized to the average fundamental period. In this way, a square wave signal synchronized with the fundamental period of the tuning target signal inputted from the outside, but with its fine period fluctuations removed, is transmitted to the PLL circuit 29.
is output from.

The positive peak hold circuit 24 and the negative peak hold circuit 25 each include a time constant circuit, and the time constants thereof are switched in accordance with the response control signal LOW. In addition, PLL circuit 2
Reference numeral 9 includes a voltage-controlled oscillator therein, and its oscillation frequency range is switched in accordance with the response control signal LOW.

Figure 3 shows the positive side and negative side peak hold circuits 2.
4, 25 and comparators 26, 27, the positive peak values and negative peak values of capacitors C1, C2 are held, respectively, and resistors R1,
It is discharged via R2 or R3 and R4. When the response control signal LOW is "0" (when the input signal is in the high frequency range), the transistors 31 and 32 are turned on, and the resistors R2 and R3, which have large resistance values, are short-circuited, and the time constant of the discharge circuit becomes small. Therefore, peak hold suitable for high frequency input signals can be achieved. When the response control signal LOW is "1" (when the input signal is in the low frequency range), the transistors 31 and 32 are turned off, and the time constant of the discharge circuit becomes large. Therefore, peak hold suitable for low frequency input signals can be achieved.

FIG. 4 is a diagram showing an example of the PLL circuit 29, in which the output of the voltage controlled oscillator (VCO) 33 and the output of the flip-flop 28 (FIG. 2) are connected to the phase comparator 3.
4 and its output is applied to the control input of the VCO 33 via the low-pass filter 35. VCO33
A response control signal LOW is also input, and when the signal LOW is "0", the oscillation frequency range is set to a predetermined high range, and when it is "1", it is set to a predetermined low range.

Returning to FIG. 2, the square wave signal output from the PLL circuit 29 is given to the period measurement control circuit 36. The period measurement control circuit 36 is for controlling the period measurement counter 37 to measure the period of the square wave signal output from the PLL circuit 29. The period measurement operation will be explained with reference to the timing chart in FIG. A reset signal is applied to input R to reset the old count contents. Next, the period from when the input square wave signal (output of the PLL circuit 29) whose period is to be measured rises to "1" to when it rises to "1" next time is 1.
During the period, a signal "1" is applied to the enable input EN of the counter 37 to enable counting. When counting becomes possible, the counter 37 sequentially counts the clock pulses provided from the clock oscillator 38. When one cycle to be measured is completed, the signal of the enable input EN falls to "0", the counting operation of the counter 37 is stopped, and the counter 3
4 holds a count value corresponding to the length of one cycle. At the same time, an end signal EOC is output from the control circuit 36 and applied to the microcomputer 12 via the interface 17. Further, the count value of the counter 37 is also given to the microcomputer 12 via the interface 17. The microcomputer 12 takes in and stores the count value of the counter 37 when the end signal EOC is generated as period measurement data of the externally inputted tuning target signal. Note that if the cycle is extremely long, the count value of the counter 37 will reach the maximum value before one cycle ends. In such a case, a signal MAX indicating that the maximum count value has been reached is output from the counter 37 and given to the control circuit 36, and based on this, the signal of the enable input EN is forced to "0" to stop the counting operation. and hold the maximum count value.

Next, the processing related to the tuning function executed by the microcomputer 12 will be explained with reference to FIGS. 6 and 7. Note that FIG. 8 lists the names and symbols of the main registers used in this program.

When the tuning function is selected, the program shown in FIG. 6 performs other program processing (for example, key press detection scanning, sound generation assignment processing, operation detection scanning of the operator circuit, data transfer processing to the tone forming circuit 13, etc.) is executed as appropriate between executions.

First, in step 39, the start register is
Check whether TSTART is "1", and if NO, proceed to step 40, output start signal START,
Next, the register TSTART is set to "1". By outputting the start signal START, the measuring circuit 16 (FIG. 2) starts counting for measuring the period of the external input signal, as described above.

If you want to execute the program shown in Figure 6 when the counting operation has already started, step 39 is
If the answer is YES, the process advances to step 41 to check whether the aforementioned end signal EOC has been given. If YES, the count value of the counter 37 is taken into the period measurement value register TCD and stored. Next, output the start signal START again to prepare for the next cycle measurement.

In step 42, the latest key code register
Compare the contents of NKC and reference key code register RKC. The latest key code register NKC is a register that is subjected to storage control in the key press detection scanning process, and stores the key code for the most recently pressed key. Reference key code register RKC
stores the key code of the key corresponding to the reference pitch. When the latest key code does not match the current reference key code, that is, step 42
When “NKC≠RKC?” is YES, step 4
Proceed to step 3 and write the contents of the latest key code register NKC to the reference key code register RKC. In this way, the contents of the reference key code register RKC are always updated with the key code of the latest pressed key.
The most recently pressed key becomes the reference pitch designation key.

The flow from step 43 to "return" is executed when the tuning reference pitch is changed by a new key depression. Step 4
In step 4, data indicating the note frequency of the reference pitch (the frequency corresponding to the note name of the reference pitch in a specific octave, for example, the lowest octave, regardless of the octave of the reference pitch specified key) is obtained based on the reference key code of the register RKC, and this reference pitch is calculated based on the reference key code of the register RKC. Based on pitch note frequency data (that is, frequency data corresponding to a pitch shift of 0 cents), each boundary value of pitch shift width corresponding to each display segment 1a to 1n (for example, +1, +3, +10, +20, +30 ，
+40, +80, -1, -3, -10, -20, -30, -40, -
80
The frequency of each boundary value (cents) is calculated, and the reciprocal of the frequency of each boundary value is taken to convert it into data indicating the period, and the period data of each boundary value is stored in the boundary value data register BDD. The comparison between the reference pitch and the pitch of the external input signal is not performed using data indicating the reference pitch itself, but using pitch data corresponding to the boundary value of the pitch deviation width corresponding to each display segment 1a to 1n. It is starting to be done. To this end, in the process of step 44, each boundary value is converted from a cent value to pitch data (periodic data in this example) corresponding to the reference pitch. In addition, the register
The reason why the pitch data of each boundary value stored in the BDD is made into period data is to match the period of the external input signal, which is measured in the measurement circuit 16 (FIG. 2).

Steps 45, 46, and 47 are processes for initial setting, and when the reference pitch is changed, these processes are performed to temporarily return to the initial state. In step 45, the response control signal LOW is set to "1" and output (corresponding to the bass range). In step 46, the octave data of the octave register TOCT is set to "0" indicating the lowest octave. The octave register TOCT is used to automatically determine the octave range of an external input signal, and searches for the octave of the external input signal while sequentially increasing the octave data stored there. As is clear from this initial setting, the octave search for the external input signal is performed from the low octave side. In this case, the cycle data of each boundary value stored in the boundary value data register BDD is determined based on the note frequency of the reference pitch in the lowest octave. In step 47, a start signal START is output.

If the reference pitch has not been changed, "NKC≠RKC?" in step 42 is NO, and the process advances to step 48. In step 48, the contents of the octave register TOCT are raised to a power of 2 by the number of octaves corresponding to the number of octaves (2 ^TOCT ), and this is multiplied by the contents of the period measurement value register TCD (TCD*2 ^TOCT ).
The contents of the register TCD are rewritten according to the multiplication result. Initially, TOCT is "0", so the contents of register TCD do not change. When the number of octaves of TOCT changes from "1" to "2" to "3", etc., the period measurement value of the register TCD changes from 2 times, 4 times, 8 times, etc. in octave units. This step 48
is the reference pitch (i.e., the period data of each boundary value in register BDD) and the pitch of the external input signal (i.e., the period measurement value data in register TCD)
This is a process to match or bring the octave ranges closer together. register as mentioned above
The cycle data of each boundary value in the BDD corresponds to the lowest octave, so if the octave of the external input signal is higher than the lowest octave, you can increase the octave of the data in the register BDD by that amount ( (dividing the BDD period data by 2 ^TOCT ), the calculation is cumbersome because there are many boundary values. Therefore, by multiplying the cycle measurement value data of register TCD by 2, 4, or 8 times, without changing the data in register BDD, the octave of the external input signal is apparently lowered.
Depending on how many octaves the external input signal is lowered (in other words, depending on the contents of the octave register TOCT), it becomes clear how many octaves above the lowest octave the external input signal is.

In step 49, the boundary value data register
Minimum period data TCMIN corresponding to the outermost boundary values of +80 cents and -80 cents from BDD
(corresponds to +80 cents) and maximum cycle data TCMAX
(corresponding to -80 cents) and register
The cycle measurement value data in the TCD is compared to check whether the cycle measurement value data is within the range of TCMIN and TCMAX. If it is within the range, the LED display program 50 is executed to light up any one of the display segments 1a to 1n made up of LEDs. If it is not within the range, the process advances to step 51 and the contents of the octave register TOCT are incremented by one.
If the contents of the octave register TOCT correspond to the octave of the external input signal, the judgment "TCMIN<TCD<TCMAX?" in step 49 is satisfied, and the pitch shift can be displayed using segments 1a to 1n. . But the register
If the contents of TOCT do not yet correspond to the octave of the external input signal, the judgment in step 49 is not satisfied, and the pitch shift is corrected for segments 1a to 1n.
cannot be displayed using . Therefore, by the process of step 51, the octave register is
TOCT is further increased by 1 and the octave search for the external input signal is continued.

Step 52 provided in the loop for octave search is for determining the switching condition of the response control signal LOW. In this example, the effective number of octaves is 5, and the octave data corresponding to each octave is "0", "1", "2", "3", "4", starting from the lowest octave.
”
It is said that it is. The three octaves on the bass side are defined as the low range, and the two octaves on the high range are defined as the high range, and the response control signal LOW is switched depending on which range the external input signal belongs to. Therefore, in step 52, it is determined whether the content of the octave register TOCT is "3", and if YES, the external input signal belongs to the high range, so in step 53, the response control signal LOW is set to "0". As a result, the measurement circuit 16
Since the period measurement conditions in (Fig. 2) change,
It is preferable to measure the period again with high accuracy.
Therefore, in step 54, a start signal START is output to cause period measurement to be performed.

On the other hand, if step 52 is NO, the process proceeds to step 56 via step 55, and the register is
Double the period measurement in the TCD. This is a process corresponding to the increment of the contents of the octave register TOCT by 1 in step 51, and
Lower the TCD period measurement value by one octave. Thereafter, the process returns to step 49 and the above-described determination is repeated.

Step 51 until step 49 becomes YES
-56 loops are repeated to search the octave of the external input signal. Step 55 is to check whether the search has been performed beyond the predetermined highest octave, and if the contents of the register TOCT are less than or equal to the valid maximum value of octave data "4",
TOCT=“5”? is NO, proceeding to step 56 and continuing the octave search loop. However, if the octave of the external input signal cannot be determined within the valid number of octaves, step 55
YES, and the process returns to steps 45, 46, and 47 (initial settings).

The LED display program 50 will be explained with reference to FIG. 7. In step 57, the upper limit of the pitch shift width corresponding to the currently lit segment (one of 1a to 1n) is determined based on the contents of the lighting segment number register LEDNO. Read the lower limit boundary value data from register BDD. For example +1 to +3
When the segment corresponding to the cent pitch deviation width is lit, periodic data corresponding to +1 cent is read out as lower limit boundary value data, and periodic data corresponding to +3 cents is read out as upper limit value data. The register LEDNO stores the number of the currently lit segment. In addition,
Although display segments corresponding to pitch deviation widths of +40 to +80 cents and -40 to -80 cents are not actually provided, the register LEDNO stores the number data as if the corresponding segments were provided. can do. The contents of the register LEDNO are initially - in the initial state.
The number of the center segment corresponding to the pitch deviation width of 1 to +1 cent is shown. It is assumed that the segment number has a larger value as it corresponds to a higher pitch, and a smaller value as a segment number corresponds to a lower pitch.

In step 58, the upper and lower boundary values of the currently lit segment read in the previous step 57 are compared with the contents of the period measurement value register TCD, and the pitch deviation of the external input signal with respect to the reference pitch is determined by the pitch deviation of the currently lit segment. Determine whether it is within the range of a segment. In step 58, the following (A),
Make either one of (B) or (C).

(A) The period measurement value data of register TCD is greater than the period data of the lower limit boundary value. In other words, the pitch of the external input signal is lower than the currently lit segment.

(B) The period measurement value data of register TCD is between the lower limit boundary value and the upper limit boundary value. In other words, the pitch of the external input signal corresponds to the currently lit segment.

(C) The period measurement value data of register TCD is smaller than the period data of the upper limit boundary value. In other words, the pitch of the external input signal is higher than the currently lit segment.

In steps 59 to 61, the counting operations of the high side movement counting register HCNT and the low side movement counting register LCNT are controlled according to the result of the judgment at step 58.
The high side movement count register HCNT is used to set a response delay between judgment and switching operation when switching the segment to be lit to an adjacent segment on the high pitch side. Low side movement count register
The LCNT is used to set a response delay between the decision and the switching operation when switching the segment to be lit to an adjacent segment on the lower pitch side. Addition or subtraction is performed on the contents of each register HCNT and LCNT.
When the subtraction progresses and the contents of the registers HCNT and LCNT reach "0", they do not respond to subsequent subtraction instructions and remain "0".

First, a case in which the above-mentioned judgment condition (A) is satisfied will be described. In step 59, the contents of the register HCNT are subtracted by 1, and the contents of the register LCNT are incremented by 1. Next, in step 62, the register
Check whether the content of LCNT is greater than "10".
If NO, return and step 57, 58, 5
Repeat steps 9 and 62. Each time it is repeated, the count value of register LCNT increases by 1, and eventually
If the content of LCNT exceeds “10”, step 6
Proceed to step 63 from YES in step 2. Step 6
In step 3, "5" is set in the register LCNT.
Next, in step 64, "1" is subtracted from the contents of the lighting segment number register LEDNO, and the segment number to be stored is rewritten to the number of the segment adjacent to the currently lighting segment on the lower pitch side.
In step 65, the contents of the register LEDNO are output to the display control circuit 15 (Fig. 2), and the contents of the register LEDNO are output to the display control circuit 15 (Fig. 2).
Lights up the segment corresponding to the segment number stored in LEDNO. Thus, if the pitch of the external input signal is lower than the pitch corresponding to the currently lit segment, the lit segment is switched to an adjacent segment on the lower pitch side.

If the judgment condition (A) is still satisfied even after switching the lighting segment to an adjacent segment, it is necessary to switch the lighting segment to an adjacent segment on the lower pitch side, so steps 57, 58, and 5 are performed.
9 and 62 are repeated to count up the contents of register LCNT. In this case, the register
LCNT is preset to "5" in step 63, so when the contents of LCNT are counted up six times, "LCNT >10?" is displayed in step 62.
becomes YES. Based on this, steps 63, 64, and 65 are executed in the same manner as described above, and the lit segment is further switched to an adjacent segment on the lower pitch side.

In this way, the lit segments are sequentially switched to adjacent segments until the segment corresponding to the pitch shift of the external input signal is lit.

When the lighting segment corresponds to the pitch shift of the external input signal, the judgment condition (B) of step 58 is satisfied. In that case, in step 60, the contents of both registers HCNT and LCNT are each subtracted by 1, and the process returns.

In this way, from when judgment condition (A) is first satisfied until judgment condition (B) is satisfied, when switching the lighting segment to the adjacent segment for the first time, the LCNT is set to ``10'' without going through step 63. ”
After that, when switching the lighting segment to an adjacent segment, the LCNT is preset to "5" in step 63 and the count is continued until it exceeds "10". register
The switching of lit segments is delayed until the content of LCNT exceeds 10, and this delay time is longest when first switching to an adjacent segment, and shorter when switching to sequentially adjacent segments. It's also short. This is because in the former case, counting starts from "0" or at least a number smaller than "5" to "11".

The reason why the contents of the register HCNT are subtracted by 1 in step 59 is that when moving the lighting segment in the opposite direction (towards a higher pitch) in the future, the 1 addition count of the register HCNT in step 61 starts from the smallest possible number. This is to increase the response delay at the start of movement. The reason why the contents of both registers HCNT and LCNT are subtracted by 1 in step 60 is for the same reason; no matter whether the lighting segment is moved to the high pitch side or the low pitch side in the future, the response at the start of the movement will be This is to increase the delay.

If the above judgment condition (C) is satisfied, proceed to step 6.
1, and the processes of steps 66, 67, 68, and 69 are executed. These processes are performed in step 5 above.
9, 62 to 65, and the relationship between registers HCNT and LCNT is exactly reversed. That is, in step 61, the register
Add 1 to the contents of HCNT and subtract 1 from the contents of register LCNT. In step 66, the register
It is determined whether the contents of HCNT exceeds "10", and in step 67 the register HCNT is preset to "5". In step 68, the contents of the lighting segment number register LEDNO are incremented by 1 and rewritten to the number of the segment adjacent to the currently lit segment on the high pitch side. In step 69, the register
The contents of LEDNO are output to the display control circuit 15, and the segment corresponding to the rewritten segment number is lit. Thus, if the pitch of the external input signal is higher than the pitch corresponding to the currently lit segment, the lit segment is switched to the adjacent segment on the higher pitch side.

As described above, the flow of judgment condition (C) is repeated until judgment condition (B) is satisfied, and the number of lit segments is 1.
Move one segment at a time to the higher pitch side. Also, since "5" is preset in the register HCNT in step 67, the time delay when the lighting segment first moves to the next segment is the best, and the subsequent switching of lighting segments is the best, as described above. Time dilation is shorter than that.
Also, the reason why the contents of the register LCNT are decremented by 1 in step 61 is the same as described above, and in the future, the lighting segments will be moved in the opposite direction (toward the lower pitch side).
This is to increase the response delay at the start of movement by starting the 1 addition count of register LCNT in step 59 from the smallest possible number when moving.

By the above processing, for example -40 to -30
Segment 1a corresponding to cent pitch deviation width
When switching the lighting segment from a state in which is stably lit to segment 1d, which corresponds to a pitch deviation width of -10 to -3 cents, when lighting is first switched from segment 1a to segment 1b, set "1" in register HCNT. '' to ``11'' and the count changes relatively slowly, but then 1b
When the lighting changes from 1c to 1c, further from 1c to 1
When the lighting is switched to d, the register HCNT counts from ``6'' to ``11'' and the switching occurs relatively quickly. Then, when the lighting position stops moving at segment 1d, the register
The HCNT performs a subtraction counter from "5" to "0". In this way, by making the response delay when starting to move the lighting position larger than the response delay during movement, it is possible to make the continuous switching operation of the lighting segments similar to the movement of a mechanical pointer. It will be easy to see.

Note that although the outermost pitch deviation widths -80 to -40 cents and +40 to +80 cents do not actually have corresponding display segments, these pitch widths are applied as if there were corresponding display segments. Register the corresponding segment number
The LED display program 50 of FIG. 7 is executed with respect to these pitch widths. Accordingly, when the contents of the period measurement value register TCD correspond to these pitch widths, step 49 in FIG.
The answer is YES, and the process does not proceed to step 51, which is the process of counting up the octave register TOCT.
Therefore, by operating the LED display lamp 50 even for pitch widths that are not actually lit, it is possible to prevent the octave register TOCT from being counted up frequently, and accordingly, the response control signal LOW is suppressed. Frequent switching can be suppressed, unnecessary fluctuations in measurement conditions in the measurement circuit 16 can be suppressed, and period measurement can be performed under stable conditions.

Note that in the above embodiment, register BDD
Each boundary value data stored in the register is a periodic representation of the actual pitch at each boundary.
The cycle measurement value data of the TCD and the upper and lower boundary value data read from the register BDD are directly compared in step 58 of FIG. However, the present invention is not limited to this. Data indicating the pitch deviation of each boundary pitch with respect to the reference pitch is stored in the register BDD, and in step 58, the difference between the period of the reference pitch and the period measurement value is calculated, and this difference is calculated. The upper limit and lower limit boundary value data in the pitch deviation data format may be compared. Also,
The data representation format of the pitch deviation or pitch is not limited to data corresponding to the period, but may also be numerical data corresponding to the frequency or the cent value itself.

In the embodiments described above, the present invention is implemented using a microcomputer, but it goes without saying that implementation using a dedicated discrete circuit is also within the scope of the present invention.

Further, although the keyboard KB is used as a means for specifying the reference pitch, the present invention is not limited to this, and any other appropriate pitch selection operator may be used.

Further, in the above embodiment, the tuning device is built into the electronic musical instrument, but the above-mentioned tuning function-related parts may be made independent to form a single tuning device.

〔Effect of the invention〕

As described above, according to the present invention, when a display segment corresponding to a pitch deviation of an input signal with respect to a reference pitch is to be brought into an indication state, the indication state is immediately switched from the segment currently in an indication state to the target segment. Instead, the segments in the indicated state are switched one segment at a time to the adjacent segments, making it easier to see. Also, a response delay is set when switching the segment that should be in the instruction state, so
Frequent fluctuations in the display can be suppressed to make it easier to see, and the movement can also be made to resemble the movement of a mechanical hand, making it even easier to see.

[Brief explanation of drawings]

FIG. 1 is a conceptual block diagram showing the basic configuration of this invention, FIG. 2 is a block diagram showing the hardware configuration of an embodiment of this invention, and FIG. 3 is a positive side and negative side of the measuring circuit of FIG. 2. Figure 4 is a block diagram showing a detailed example of the peak hold circuit and comparator in the measurement circuit, Figure 4 is a block diagram showing an example of the phase lock loop circuit in the measurement circuit, and Figure 5 is the input/output of the period measurement control circuit in the measurement circuit. A timing chart showing an example of a signal, FIG. 6 a flowchart showing an example of a tuning function program executed by the microcomputer in FIG. 2, and FIG. 7 showing an example of the LED display program in FIG. 6. The flowchart, FIG. 8, is a diagram showing the main registers used when executing the programs of FIGS. 6 and 7. 1a to 1n... multiple display segments, 2...
Segment specifying means, 3... Measuring means, 4... Judgment means, 5... Switching means, KB... Keyboard, 10...
... Key switch circuit, 12 ... Microcomputer, 13 ... Musical tone forming circuit, 16 ... Measurement circuit, LEDNO ... Lighting segment number register,
HCNT……High side movement count register, LCNT……
Low side movement count register.

Claims (1)

[Scope of Claims] 1. Measuring means for measuring the frequency or period of an input signal; a plurality of display segments provided corresponding to the magnitude of pitch deviation with respect to a reference pitch; and an indicated state of the plurality of display segments. segment specifying means for specifying a segment in the indicated state; and determining whether the pitch deviation of the input signal with respect to the reference pitch corresponds to the segment in the indicated state, based on the measurement result by the measuring means and the output of the segment specifying means. a determining means for determining whether the pitch deviation corresponds to the segment in the indicated state, and when the determining means determines that the pitch deviation does not correspond to the segment in the indicated state, the segment that should be in the indicated state next is replaced with the segment currently in the indicated state; A tuning device comprising: a switching means for switching to a segment adjacent to the segment, and sequentially performing this switching for the adjacent segments until the segment corresponding to the pitch deviation is in an instruction state. 2. When the determining means determines that the pitch deviation does not correspond to the segment in the instruction state, the switching means sets a predetermined response delay and then switches the segment to be in the instruction state to the segment in the instruction state. The tuning device according to claim 1, wherein the tuning device switches between adjacent segments. 3. The switching means is configured to switch between the time when the determining means first determines that the pitch deviation does not correspond to the segment in the instruction state and the time when the segment corresponding to the pitch deviation becomes the instruction state. In the present invention, the response delay when the segment to be in the indicated state is first switched to the adjacent segment is set to be larger than the response delay when the segment is switched after that. The tuning device according to item 2. 4. Claim 2, wherein the switching means includes a counting means that performs addition or subtraction counting according to the determination result of the determining means, and the response delay is set based on the value of the counting means. Or the tuning device according to paragraph 3. 5. The counting means is a first counting means used for setting the response delay when moving a segment to be in an instruction state to a high pitch side, and a first counting means used for setting the response delay when moving a segment to be in an instruction state to a low pitch side. and a second counting means used to set the response delay, and the pitch deviation corresponds to a segment on the higher pitch side than the segment currently in the instruction state, and corresponds to a segment on the lower pitch side. 5. The tuning device according to claim 4, wherein the first and second counting means are in an addition or subtraction counting state in opposite directions depending on the case. 6. The tuning device according to claim 1, wherein the segment specifying means comprises a storage means for storing information indicating which segment is in the designated state among the plurality of segments.