JP3671236B2 - Keyboard drive device - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a keyboard driving apparatus that automatically presses and releases a keyboard according to performance data.
[0002]
[Prior art]
In such a keyboard driving device, a plunger, solenoid or other actuator (drive mechanism) is provided for each key, and when the performance data event is a key depression, the actuator corresponding to the key to be depressed is provided. Turn on the drive signal. When the performance data event is a key release, the actuator drive signal corresponding to the key to be released is turned off. Therefore, when the performance data event is a chord, a drive signal for simultaneously pressing and releasing a plurality of keys corresponding to the chord is given to the actuator.
[0003]
[Problems to be solved by the invention]
By the way, when keys are pressed simultaneously like chords, or when keys are pressed repeatedly for the same period other than chords, the load on the power supply for supplying drive signals to the actuators that drive the corresponding keys is also large. Become. Therefore, the maximum number of keys to be pressed simultaneously or during the synchronization is limited. For this reason, in the keyboard driving device, the key pressing process has to be omitted for performance data exceeding the maximum number of keys.
An object of the present invention is to perform a key pressing process even when performance data to be pressed exceeds the maximum number of keys that can be driven simultaneously.
[0004]
[Means for Solving the Problems]
This invention Supplied According to the driving signal Drive the key Driving means, Only a predetermined number of key number data can be stored When there is no free area in the first storage means and the first storage means, Key number Second storage means for storing data and stored in the first storage means Key number To data For driving the corresponding key Drive signal To drive means give Drive signal Supply Means, When the performance data sequentially supplied in accordance with the processing timing is key depression data, if there is an empty area in the first storage means, the key number data in the performance data is stored in the empty area, while the first data When there is no empty area in the storage means, the second storage means is controlled to store the key number data. Further, if the supplied performance data is key release data, The areas of the first and second storage means in which data having the same key number as the key number data are stored are made empty, an empty area is generated in the first storage means, and the key number data is stored in the second storage means Is stored, the key number data is transferred to the empty area of the first storage means, and the area where the key number data is stored in the second storage means is made empty. And a storage control means.
According to this configuration, when there is performance data to be pressed exceeding the maximum number of keys that can be driven, information on the key to be pressed (Key number data) Is temporarily held, and when any of the keys being driven is released, the key pressing process is performed based on the information of the held key.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, first and second embodiments of the present invention will be described with reference to FIGS.
FIG. 1 is a diagram showing a system configuration of first and second embodiments when a keyboard driving device according to the present invention is applied to an electronic musical instrument. The CPU 1 exchanges commands and data with the following units connected to the system bus to control the entire electronic musical instrument. The ROM 2 stores a control program executed by the CPU 1 and initial data in initialization processing after power-on. The RAM 3 stores data processed by the CPU 1. The keyboard 4 inputs a key number and other data to the CPU 1 in accordance with a key pressing operation and a key releasing operation. The input data is temporarily stored in the RAM 4, and a sound generation process and a mute process are performed.
[0006]
The plunger 5 is a keyboard driving means for automatically pressing and releasing the keyboard according to performance data, instead of the performer. The plunger driver 6 is a signal generating unit that generates a drive signal to be given to the plunger 5 in accordance with a command from the CPU 1. The switching circuit 7 relays an actual current for driving the plunger 5 from the power supply 8 in accordance with the drive signal. The timer 9 inputs a timer interrupt to the CPU 1 at regular intervals. The timer interrupt will be described later. The sound source 10 generates a musical sound signal based on the sound generation command and the mute command from the CPU 1 and sends it to a sound system (not shown). The MIDI interface 11 transmits / receives MIDI data to / from an external MIDI device.
[0007]
The automatic performance data memory 12 stores automatic performance data input in advance or MIDI data input from the MIDI interface 11 as automatic performance data. As shown in FIG. 2, the automatic performance data in the automatic performance data memory 12 is composed of an event and data of processing timing of the event, and is sequentially read by a read command from the CPU 1. When the event is a chord, the processing timing of the plurality of events is the same timing. The CPU 1 issues a key depression command and a key release command to the plunger driver 6 based on the automatic performance data.
[0008]
FIG. 3 (1) is a cross-sectional view showing the structure of the keyboard 4. Each key 41 has a tip portion 41 a fixed to the frame 42. At a predetermined position on the lower side of the key 41, a switch pressing portion 41b is provided so as to protrude downward. Two key-pressing touch detection switches 43 are provided at the position of the frame 42 facing the switch pressing portion 41b. The key pressing and key release are detected and the detection signal is input to the CPU 1. The CPU 1 issues a sound generation instruction and a mute instruction to the sound source 10 according to the detection signal. A protrusion 41c is provided between the tip 41a and the switch pressing part 41b on the lower side of the key 41. One end of the coil spring 44 is fixed to the protrusion 41 c and the other end is fixed to the frame 42. The key 41 is biased upward by the coil spring 44, and a repulsive force is applied to the key pressing operation.
[0009]
A plunger 5 is fixed at a predetermined position of the frame 42. Further, a key drive arm 45 is attached in the vicinity of the plunger 5 so as to be rotatable with respect to the shaft 45a. The key drive arm 45 is biased toward the plunger 5 by a spring (not shown) provided on the shaft 45a, and abuts against the lower protrusion 41d of the key 41 by the extension force of the coil spring 44. It is energized. Therefore, when the plunger 5 is not driven, the key driving arm 45 is pressed against the movable portion 5a of the plunger 5 as shown in FIG.
[0010]
Now, when a drive signal is given to the plunger 5 from the plunger driver 6, the movable part 5a of the plunger 5 protrudes to the key drive arm 45 side. As a result, as shown in FIG. 3B, the key drive arm 45 rotates downward to press the lower protrusion 41d of the key 41 downward, and the key 41 is a leaf spring of the tip 41a. Depending on the structure, it will bend down and be automatically pressed. At this time, the key pressing touch detection switch 43 is turned on when the switch pressing portion 41b of the key 41 is pressed. In this case, the two key pressing touch detection switches 43 are not turned on at the same time but are turned on with a time difference. This time difference changes according to the key pressing speed. When the drive signal to the plunger 5 is turned off, the key 41 returns to the state shown in FIG. 3A by the biasing force of the coil spring 44 and the spring of the leaf spring structure of the tip 41a of the key 41.
[0011]
Therefore, when the key is depressed, the key driving arm 45 needs to rotate so as to exceed the urging force of the spring of the leaf spring structure of the coil spring 44 and the tip 41a of the key 41. The current required for the operation is supplied to the plunger 5. Therefore, since the load of the power source 8 increases as the number of keys pressed simultaneously increases, the maximum number of keys pressed simultaneously is limited. Incidentally, the maximum number of keys is limited to 6 in the first and second embodiments.
[0012]
Next, the concept of performance data processing in the first and second embodiments will be described with reference to FIGS. Data for simultaneous processing, such as chord data, in the event data of the automatic performance data memory 12 is temporarily stored in the temporary memory area 31 of the RAM 3 shown in FIG. Therefore, as shown in FIG. 5, the event data stored in the temporary memory 31 has the same data format as the automatic performance data memory 12 shown in FIG. The data discriminating function of the CPU 1 discriminates whether or not there is an empty area in the state memory 32 of the RAM 3 that can transfer all the event data in the temporary memory 31. If there is an empty area, the event data is stored in the state memory 32. If there is not enough free area, event data that cannot be transferred is transferred to the hold memory 33.
[0013]
As shown in FIG. 5, the data format of the state memory 32 is composed of a key number, an off flag, and time data T that changes according to a timer interrupt. Off flag 1 Indicates that the key is released, and when the off flag is 0, it indicates that the key is pressed. Further, the data format of the holding memory 33 is composed only of the key number. The CPU 1 monitors the plunger driver 6 to determine whether or not the drive signal is turned off, and when it is turned off, the off flag of the corresponding state memory 32 is changed from 0 to 1 to free the area. The event data stored in the reserved memory 33 is transferred to the empty area. Further, the sound source 10 is instructed to generate sound and mute according to the keyboard drive state.
[0014]
For example, as shown in FIG. 6, when note 1 to note 5 are simultaneously depressed and the key depression event data of note 6 at processing timing t1 is transferred to temporary memory 31, the maximum key depression Since there is one vacant area for Equation 6, the event data of Note 6 can be transferred to the state memory 32 to perform the key pressing process. After that, when the notes 1 to 6 are being depressed and the event data of the note 7 is transferred to the temporary memory 31, there is no one empty area for the maximum number of depressed keys 6. The event data is stored in the holding memory 33.
[0015]
When the note 5 is turned off at the timing t2, the event data of the note 7 is transferred from the holding memory 33 to the state memory 32 at that time. In addition, the event data of note 8 in a state where there is no free area in the state memory 32 But When transferred to the temporary memory 31, the event data of the note 8 is transferred to the hold memory 33. When the note 6 is turned off at the timing t3, the event data of the note 8 is transferred from the hold memory 33 to the state memory 32 at that time. Forward to.
[0016]
Next, the operation of the first embodiment will be described in detail with reference to the flowchart of the CPU 1.
In the main flow of FIG. 7, after the initialization process (step S1), a loop that repeats the data read / write process (step S2), the sound generation process (step S3), and other processes (step S4) is executed.
[0017]
In the data read / write process in step S2, as shown in FIG. 8, it is determined whether or not data remains in the temporary memory 32 (step S5). When no data remains, data consisting of an event and processing timing is read from the currently designated area of the automatic performance data memory 12 (step S6), and the data is stored in the temporary memory 31 (step S7). Next, the next area of the automatic performance data memory 12 is designated (step S8). Then, it is determined whether or not the processing timing of the designated area immediately before the automatic performance data memory 12 is the same as the processing timing of the current designated area (step S9).
[0018]
Since these data represent chords at the same timing, it is necessary to perform a key pressing process at the same time. Therefore, the process proceeds to step S6, and the data of the current designated area is read. In step S9, when the processing timing of the immediately preceding designated area is different from the processing timing of the current designated area, whether or not the processing timing of the data in the temporary memory 31 is the current value of the timer 9 in the flow of FIG. That is, it is determined whether it is the event start time (step S10). If data remains in the temporary memory 31 in step S5 in FIG. 8, the process proceeds to step S10 in FIG. 9 without reading the data from the automatic performance data memory 12, and the data in the temporary memory 31 is read. It is determined whether or not the processing timing is the event start time.
[0019]
In step S10, when the data processing timing in the temporary memory 31 is not the event start time, the process returns to the main flow. When the processing timing is the event start time, the event data is read from the non-empty area of the temporary memory 31 and the area is made empty (step S11). Then, it is determined whether the read event data is key-on data for turning on the keyboard 4 or key-off data for turning off the keyboard 4 (step S12). If it is key-on data, whether or not there is an empty area in the state memory 32 is determined based on the presence or absence of a key number (step S13). If there is a free area, the key number is stored for the free area, 0 is set in the off flag, and 0 is set in T (step S14). Then, it is determined whether or not all the areas of the temporary memory 15 are empty (step S15). On the other hand, if there is no empty area in the state memory 32 in step S13, the key number is stored in the first empty area of the reserved memory (step S16). Then, the process proceeds to step S15, and it is determined whether or not all areas of the temporary memory 31 are empty.
[0020]
When all the areas of the temporary memory 15 become empty, the process returns to the main flow. However, when there is an area that is not empty, the process proceeds to step S11 and data is read from the area that is not empty. In step S12, when the read event data is key-off data for turning off the keyboard 4, it is determined whether or not the key number to be turned off is stored in the holding memory 33 (step S17). If not stored, the area of the state memory 32 in which the key number to be turned off is stored is searched (step S18). Then, 1 is set to the off flag of the found area, and 0 is set to T (step S19). Next, the process proceeds to step S15, and it is determined whether or not all areas of the temporary memory 31 are empty. In step S17, when the key number to be turned off is stored in the holding memory 33, the stored area is made empty, and data below the area is left-justified in the empty area (step S20). Thereafter, the process proceeds to step S15, and it is determined whether or not all areas of the temporary memory 31 are empty.
[0021]
10 and 11 are flowcharts of the timer interrupt process. When a timer interrupt is entered every 10 ms, it is determined in FIG. 10 whether there is a non-empty area in the state memory 32 (step S21). If there is an area that is not empty, the first area in which data is stored is designated (step S22). Next, 10 (ms) is added to T of the designated area (step S23), and the added T is divided by the reference time TB (in this case, TB = 40 ms) (step S24) to obtain the quotient A and the remainder. Find B. Then, the values of the quotient A and the remainder B are compared (step S25).
[0022]
When A is larger than B, it is determined whether or not the off flag of the designated area is 1, that is, whether or not the event of the area is muted (step S26). When the off flag is 0 (sounding), a plunger signal ON is sent to the plunger driver 6 corresponding to the key number of the area (step S27). On the other hand, when the off flag is 1 (silence), a plunger signal OFF is sent to the plunger driver 6 corresponding to the key number of the area (step S28).
[0023]
If A is B or less in step S25, it is determined whether or not the off flag of the designated area is 1 (step S29). If the off flag is 0 (sounding), a plunger signal off is sent to the plunger driver 6 corresponding to the key number of the area in step S28. On the other hand, when the off flag is 1 (silence), in step S27, a plunger signal ON is sent to the plunger driver 6 corresponding to the key number of the area.
[0024]
After sending the plunger signal on or off in step S27 or step S28, it is determined whether or not the off flag of the designated area is 1 (silence) (step S30). If the off flag is 1, T Is greater than 160 ms (step S31). If T is larger than 160 ms, the designated area is made empty (step S32). Then, it is determined whether or not there is a non-empty area after the designated area (step S33). If the off flag is 0 in step S30, or if T is 160 ms or less in step S31, it is determined whether there is a non-empty area after the area designated in step S33. When there is an area that is not empty, the found area is designated (step S34), and the process proceeds to step S24 to calculate T / TB.
[0025]
In step S33, when there is no empty area after the area specified in the state memory 32, or when the state memory 32 is all empty areas in step S21, in the flow of FIG. It is determined whether or not there is (step S35). If there is a free area, the first area in which data is stored is designated (step S36). Next, it is determined whether or not there is an empty area in the state memory 32 (step S37). If there is an empty area, the key number data stored in the holding memory 33 is moved to the empty area of the state memory 32. Then, the off flag in that area is set to 0, and 0 is set to T (step S38).
[0026]
Next, the designated area of the holding memory 33 is made empty (step S39). Then, it is determined whether or not the next area of the holding memory 33 is not empty (step S40). If the next area is not empty, the next area is designated (step S41). Then, the process proceeds to step S37 to determine an empty area in the state memory 32. If there is no empty area in the state memory 32 in step S37, or if there is no non-empty area after the area specified in the reserved memory in step S40, the data in the reserved memory 33 is left-justified. (Step S42). Thereafter, the process returns to the main flow. In step S35, if all the reserved memories 33 are free areas, the process returns to the main flow.
[0027]
FIG. 12 shows the transition of the plunger signal in response to a timer interrupt every 10 ms when TB = 40 ms.
In accordance with a timer interrupt every 10 ms (hereinafter abbreviated as “TI”), the quotient A and the remainder B of the calculation T / TB (= 40) in step S24 of FIG. 10 are the values shown in FIG. Therefore, when the off flag is 0, that is, when the key is depressed, the plunger signal is turned off by the processing of step S25, step S29, and step S28 in FIG. During the period of TI = 40 to 50, the plunger signal is turned on by the processing of step S25, step S29, and step S27 in FIG. Similarly, the period of TI = 50-80 is off, the period of TI = 80-100 is on, the period of TI = 100-120 is off, the period of TI = 120-150 is on, the period of TI = 150-160 Is off, and is always on after TI = 160. That is, the plunger signal in the key-pressing start transition period is intermittently turned on, and the on-time gradually becomes longer, and finally becomes a continuous on signal.
[0028]
On the other hand, when the off flag is 1, that is, when the key is released, the phase is opposite to that when the key is pressed. When T exceeds 160 ms, the key is completely released, so that the designated area is made empty after step S31 to step S32 in FIG.
[0029]
As described above, according to the first embodiment, when there is performance data to be pressed exceeding the maximum number of keys that can be driven, the information on the key to be pressed is temporarily held, and driving is in progress. When any one of the keys is released, the key pressing process is performed based on the information on the pending key. Accordingly, the key pressing process can be performed even when there is performance data to be pressed exceeding the maximum number of keys that can be driven simultaneously. In this case, the key pressing timing of the held key is slightly delayed from the actual performance data processing timing, that is, the sound generation timing. However, this timing shift is regarded as a so-called “pitch” and is rather mechanically accurate. It is not necessarily a drawback because it is thin and impersonal.
[0030]
Also, as shown in FIG. 12, the key is gradually depressed and released, so that the stress change with respect to the spring (not shown) provided on the shaft 44a of the coil spring 44 and the key drive arm 45 in each key shown in FIG. It becomes gentle and its fatigue level is reduced. In addition, since the peak value of the current supplied from the power source 8 to the plunger 5 when the key is depressed is reduced, there is an effect that a small and inexpensive power source having a low rated value can be used. Further, the cushioning material provided at a predetermined location of each key can also have a simple structure.
[0031]
FIG. 13 and FIG. 14 show the transition of the plunger signal according to the timer interrupt when the reference time TB is 30 ms and 20 ms. As is apparent from these two figures, the key pressing speed and the key releasing speed increase as the reference time TB decreases. Although omitted in the automatic performance data shown in FIG. 2, the event data includes velocity data indicating the key pressing speed in addition to the key number and the on / off information indicating key pressing or key release. . As described in the key structure, the two key pressing touch detection switches 43 are not turned on at the same time but are turned on with a time difference, and this time difference changes according to the key pressing speed.
[0032]
Therefore, the velocity information can be supplied to the sound source 10 by changing the reference time TB according to the velocity data included in the event data. As a result, even with the automatic key pressing by the plunger 5, it is possible to generate a sound with strength and weakness based on the velocity data in the performance data as if the person had performed.
[0033]
Next, a second embodiment of the present invention will be described with reference to FIGS.
Also in the second embodiment, as in the first embodiment, as shown in FIG. 12, key pressing and key release are gradually performed. In this case, there is a time during which no current flows from the power supply 8 to the plunger 5 in the transient state of the key pressing start. On the contrary, in the transient state of the key release start, there is a time during which current flows from the power source 8 to the plunger 5. Therefore, in the second embodiment, the key pressing and key releasing transient states are overlapped without increasing the load current of the power source 8. Therefore, the RAM 3 has a state memory having an area twice the number of keys that can be driven simultaneously. A half of the total area of the state memory is an area corresponding to key depression, and the remaining half is an area corresponding to key release.
[0034]
The main flow of the CPU 1 in the second embodiment is the same as that in the first embodiment, and the data read / write process and the timer interrupt process include many of the same processes as in the first embodiment. Therefore, in FIG.15 and FIG.16, the same process as 1st Embodiment is represented by the same code | symbol, and the description is abbreviate | omitted.
[0035]
FIG. 15 is a partial flow of data read / write processing in the second embodiment. When there is an empty area in the state memory in step S13, the off flag is 0, that is, the number of areas of the state memory in the sounding state is the state. It is determined whether or not the total number of memory areas (for example, 12 areas) is less than one half (6 areas) (step S43). If the number of areas whose off flag is 0 is less than half of the total number of areas, the process proceeds to step S14, where the key number is stored in the empty area of the state memory, 0 is set in the off flag, and T is set. Set 0.
[0036]
FIG. 16 is a flowchart of a part of the timer interrupt process in the second embodiment. When there is an empty area in the state memory in step S37, the number of areas of the state memory in the sounding state in which the off flag is 0 is set in the state memory. It is determined whether or not it is less than half of the total number of areas (step S44). If the number of areas whose off flag is 0 is less than half of the total number of areas, the process proceeds to step S38, and the key number data stored in the designated area of the reserved memory is stored in the empty area of the status memory. Then, 0 is set in the off flag, and 0 is set in T.
[0037]
FIG. 17 shows a key pressing signal and a key releasing signal for two different keys. As is apparent from this figure, the periods of the plunger signals that are turned on (high level) in the two keys do not overlap. Therefore, before any key in the key-pressed state starts to be released and completely released, it is possible to start pressing another key corresponding to the key number stored in the holding memory. . As a result, it is possible to operate the keyboard without waste.
[0038]
【The invention's effect】
According to the present invention, when there is performance data to be pressed exceeding the maximum number of keys that can be driven, information on the key to be pressed is temporarily held, and any of the keys being driven is released. When the key is locked, the key pressing process is performed based on the information on the key being held. Therefore, even when there is performance data to be pressed exceeding the maximum number of keys that can be driven simultaneously, the key pressing process can be performed.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a system of an electronic musical instrument in each embodiment of the present invention.
FIG. 2 is a diagram showing automatic performance data in an automatic performance data memory in FIG. 1;
3 is a cross-sectional view showing the structure of a key of the keyboard in FIG. 1. FIG.
FIG. 4 is a diagram showing a flow of automatic performance data according to the present invention.
5 is a diagram showing a data area of a RAM in FIG.
FIG. 6 is a timing chart showing a key pressing signal.
FIG. 7 is a main flowchart of a CPU according to the first embodiment.
8 is a flowchart of data read / write processing in FIG.
FIG. 9 is a flowchart of data read / write processing following FIG. 8;
FIG. 10 is a flowchart of timer interrupt processing in the first embodiment.
FIG. 11 is a flowchart of timer interrupt processing following FIG. 10;
FIG. 12 is a timing chart showing the transition of the key pressing signal at a certain reference time in the first embodiment.
FIG. 13 is a timing chart showing the transition of the key depression signal at another reference time in the first embodiment.
FIG. 14 is a timing chart showing the transition of the key pressing signal at another reference time in the first embodiment.
FIG. 15 is a partial flowchart of data read / write processing according to the second embodiment.
FIG. 16 is a flowchart showing a part of timer interrupt processing in the second embodiment;
FIG. 17 is a timing chart showing transition of a key press signal and a key release signal in the second embodiment.
[Explanation of symbols]
1 CPU
3 RAM
4 keyboard
5 Plunger
6 Plunger driver
10 sound sources
12 Automatic performance data memory

Claims (5)

Driving means for Ru to drive the key in response to a drive signal supplied,
First storage means capable of storing only a predetermined number of key number data ;
Second storage means for storing the key number data when there is no empty area in the first storage means;
Drive signal supply means for providing the drive means with the drive signal for driving the key corresponding to the key number data stored in the first storage means;
When the performance data sequentially supplied according to the processing timing is key depression data, if there is an empty area in the first storage means, key number data in the performance data is stored in the empty area, When there is no empty area in the first storage means, control is performed so that the key number data is stored in the second storage means, and further, when the supplied performance data is key release data The areas of the first and second storage means in which data having the same key numbers as the key number data in the performance data are stored are made empty, an empty area is generated in the first storage means, and the When the key number data is stored in the second storage means, the key number data is transferred to an empty area of the first storage means, and the key number in the second storage means is transferred. A storage control unit for the area in which data is stored in the vacant state,
A keyboard driving device comprising:   2. The keyboard driving apparatus according to claim 1, wherein the signal generating means gives a driving signal of a signal pattern for controlling a key pressing speed and a key releasing speed to the driving means.   3. The keyboard driving apparatus according to claim 2, wherein the signal generating means generates the signal pattern by calculation according to performance data.   3. The keyboard driving apparatus according to claim 2, wherein the signal generating means generates the signal pattern based on preset data.   When the storage control unit transfers key data to be pressed after key data to be released in the same area of the first storage unit, the signal pattern should be released 5. The keyboard driving apparatus according to claim 2, wherein the driving signals for the key and the key to be pressed are mutually exclusive signal patterns.

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