JPS6073693A - Channel allotter for elecronic 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 of invention] The present invention relates to a channel assignment device for an electronic musical instrument.

[Prior art]

Recently, in electronic music and musical instruments, in order to realize polyphonic electronic instruments that can produce multiple tones simultaneously, each musical tone is divided into channels and a time-sharing processing method is used to produce multiple tones simultaneously. Various things that have been made possible have been realized. Conventionally, when such channel assignment is performed, when there is no empty channel, K is assigned to the channel with the smallest envelope value after key release and the most advanced attenuation.

[Problems with conventional technology]

However, in the above method, a new sound is assigned to the channel to which the sound that is being attenuated after the key is released, so a new sound is assigned to the channel that is assigned to the sound that is being attenuated while the key is being pressed. Therefore, certain sounds were not assigned, resulting in wasted channel assignment.

[Purpose of the invention]

The present invention has been made against the background of the above-mentioned circumstances, and its purpose is to provide a channel assignment device for an electronic musical instrument that has a simple configuration, can eliminate wasteful channel assignment, and can make maximum use of the maximum number of simultaneous sounds. It's about doing.

[Key points of the invention]

In order to achieve the above object, the main point of the present invention is to allocate a new sound to a channel to which a sound that is being attenuated and being produced while a key is being pressed is also assigned a new sound to be produced.

[First Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

In the figure, 1 is a key in which a plurality of keys are arranged in the order of musical scales, and the 6 keys of this keyboard 1 are pressed by the key operation detection unit 2.
Detected in The key operation detection section 2 generates a key-on signal KO having a pulse width of M channel cycles based on the key presses and key releases of the six keys.

A key-off attenuation signal KF indicating that the key is being released (attenuated) after the key is released is output, and the channel search unit 11 (to be described later)
, the channel allocation section 12, and the envelope control section 6, and a key code is generated by pressing the six keys of the keyboard 1 and is provided to the key code memory 3.

The key code memory 3 stores and holds up to eight types of key codes using an 8-channel time-division processing method, and the channel allocation signal KOI is sent to the channel allocation unit 12 (described later).
Each time a new key code is given, a new key code is introduced into the output channel at that time, and each key code is sequentially given to the waveform generator 4. The waveform generator 4 reads a waveform value representing a musical tone waveform based on the given key code and supplies it to the multiplier 5.

This multiplier 5 is also supplied with an envelope value EC indicating the siempelope waveform by the envelope controller 6, and the above-mentioned waveform value is multiplied by the envelope value EC, and the multiplication result data is sent to the accumulator 7. It will be done. The accumulator 7 sequentially accumulates the data supplied from the multiplier 5, and the accumulated result data is supplied to the digital-to-analog converter D/A 8 at the end of each channel period of the time-division processing operation.

In the digital-to-analog converter D/A8, the data provided from the accumulator 7 is converted into an analog musical tone signal, which is amplified via an amplifier 9t and then emitted as a musical tone from the speaker 10.

Like the key code memory 8, the envelope control unit 6 generates up to eight types of envelope values corresponding to the key codes in the key code memory 8 using an eight-channel time-sharing processing method. Then, the channel assignment signal KO
Each time I is given by the channel divider 12 (described later), the output channel at that time is instructed to start a new envelope generation operation in response to a new key depression.

The output of this envelope control section 6 is given to the multiplication section 5 as described above, and the channel search section 11
You can live even for a long time.

Further, in the envelope control section 6, if the output channel is an empty channel among each channel, an empty signal E is given to the channel search section 11, the channel allocation section 12, and the key operation detection section 2. There is no key-off attenuation signal KF from the key-off, the output envelope value is being released (attenuated) while the key is being pressed, and the top three pits are "000".
In other words, if the sound is attenuated even when the key is pressed, such as a piano sound, the attenuation progresses and the level of the output sound becomes very low. The key-on attenuation signal RO output when the channel search unit 11
and is given to the channel allocation section 12.

In the channel search unit 11, an envelope control unit 6 is applied. Empty signal E1 Key-on decay signal RO
, envelope value EC, key operation detection unit 2), it is determined whether each channel is an empty channel or is being released (attenuated) after key release even if it is an assigned channel. It is determined whether the key is being pressed or being released (attenuated), and the empty channel is given the highest priority, and the allocated channel is given a certain priority condition to the one that is being released after the key is released, as described below. For those with low envelope values, the rewriting signal ψ is applied. is output and given to the channel allocation section 12.

In the channel allocation section 12, the above-mentioned key-on signal KO
, key-on attenuation signal RO, key-off attenuation signal KF, empty signal E, rewriting signal ψ0, and θ~70 channel value ah of each channel are given, and while key-on signal KO is not given, when rewriting signal ψ0 is output. When the channel value ah of the specified channel is latched and a key-on signal KO with a pulse width equal to the channel interval is given, the next new signal will be output at the same channel output as the latched channel value Ch after the next channel period. The above channel assignment signal KO for assigning the pressed key musical tone to this channel
I is given to the envelope control section 6 and the key code memory 3.

Next, with reference to FIG. 2, the specific circuit configuration of the channel search section 11 will be explained.

The top three pits of the envelope value EC from the envelope control section 6 are OR gates of 13 degrees to 13 degrees, respectively. The signal is input to a 3-bit latch 14 and a comparator circuit 15 via. Orgate 13 above. ~13s, or dirt 1 where the most significant bit (M) of the envelope value EC is given
3. , the inverted signal KF of the key-off attenuation signal is inputted, and the lower OR gate 132.13m receives inverted signals RO, RO, and the inverted key-off attenuation signal, respectively.
The outputs of the AND/DART 16 to which KF is input are respectively input. Therefore, if the sound being played/applied to the specified channel is attenuated after the key is released, KF=1
In other words, since KF = 0 "1" and "0" are binary logic levels (High and Low states, respectively), the envelope value EC is often output as the value up to i, but the specified channel If the note indexed by is a note that is being attenuated while the key is being pressed, if the envelope value EC of the top three pits is "001" to "111J", RO = 1, K.
Since F=1, the output of OR gates 13° to 133 is "111", and the envelope value EC of the top three pits is
When the value is 000J, RO=O1KF=1, so the output of or dirt 13, ~13. is 1oOJ, and even with the same envelope value, the sound that is attenuating after the key is released can be determined. A priority condition is added so that the channel has a smaller envelope value.

The latch 14 has an or gate 13. The envelope value EC through 13 is the rewriting signal ψ. The output of the latch 14 is latched at the time of the output of the comparator circuit 15.
is input.

Comparison circuit 15 includes exclusive or dirt 171 to 179-3, inverter 181% 182% and gate 191 to
193, or dirt 20, the above or dirt 13
．． ~13. If the envelope value EC from is smaller than the envelope value HCI latched in the latch 14, it is output. That is, the above OR/l'-)13. ~13
Each output of s is an exclusive orte 17. ~17. , each output of the latch 14 is applied to the or dart 17 . −
173 and and gate 19. ~19. is also given. Name Exclusive or Dirt 17. ~17. Each output of and dart 19. ~19. 19. ．． Also given in 193, exclusive or r-)17. Inverter 18. The output via
It is also given to And Dirt 19. For each exclusive or gate 17. ~17. i, the value of each bit of latch 14 and each or dart 13. ~13. It is output when the output values of the inverters 181 and 188 are different, and furthermore, when each pit of the latch 14 is larger and is "1", each AND dart 19110- to 193 is output, but due to the output of each inverter 181 and 188, the upper mismatch occurs. The comparison is given with priority, and only when the output value of the OR gates 13□ to 133 is smaller, one of the AND darts 19m to 19.0 will output.

The respective outputs of these AND gates 191 to 19 are given to an OR gate 20, and the output of this OR gate 20 is given to an OR ff-) 21. The OR gate 21 is also supplied with the output of a hold circuit 22 which will be described later, and the output of the OR gate 21 is as follows:
It is given to ANDGATE23. This AND dart 23 is controlled to open and close by an inverted signal KO of the key-on signal, and is closed while the key-on signal KO is being output, and the output of this AND dart 23 is given to an AND dart 24.

This AND gate 24 is also supplied with a channel pulse signal ψ, which is output with a slight delay from the time of each channel switching. At the output timing, the above rewriting signal ψ. The output will be closed.

The hold circuit 22 includes an OR gate 25, a latch 26, an AND gate 27, an inverter 2B, an AND dart 29, and an OR dart 30. During the channel period from output channel 0 to 7,
It is controlled so that the empeloop value latched by the latch 14 is the lowest value.

That is, the output of the AND dart 23 is OR r-) 25
The channel pulse signal ψ1 is applied to the latch 26 via e.
The output of this latch 26 is applied to an AND gate 27.

AND gate 27 contains "0" only when channel 0
The negative output eho of the channel zero signal ahO is also 4
As can be seen, the output of the AND dart 27 is fed back to the latch 26 via the OR gate 25, and is also applied to the AND dart 29 via the inverter 28. The output of the OR gate 30 to which the key-off attenuation signal KF and the key-on attenuation signal RO are applied is applied to the AND ff -) 29, and the output of the AND gate 29 is applied to the AND gate 23 via the OR gate 21. It is being

A rewrite signal ψ is an output of the channel search unit 11 configured as described above. is input to the channel allocation section 12.

The channel allocation unit 12 includes a 3-bit latch 31, an exclusive or dart 32 . ~321, Noah Gate 33, And Gate 34 and Or? -) 35, which allocates the next new key-pressed musical tone to the channel searched for by the channel search section 11.

The above 3-bit latch 31 is set to a, rooo(.

)'' to rill(7)J, when the rewriting signal ψ0 is output, the channel value ahs at that time, that is, among the channels O to 7,
Taking in the value of the channel with the smallest envelope value mentioned above, each output of each bit of this latch 31 is exclusive-or-dirt 13-321-32. are input respectively. This exclusive or dirt 321-32. , each bit value of the channel value ah is also input as is, and this exclusive OR gate 3
2. The output of ~32J+ is input to the Nordart 33.

The output of this NOR gate 33 is input to an AND gate 34, and the AND gate 34 receives the key-on signal KO.
is also input, and the output of the or-dirt 35 to which the empty signal E, key-on attenuation signal KF, and key-on attenuation signal RO are input is also input, and the output of the ANDe-) 34 is output as the channel assignment signal KOI.

Next, the operation of this embodiment will be described.

When the electronic musical instrument is powered on, each of channels 0 to 7 is repeatedly designated by time-sharing processing, but in this state, all channels are empty and no musical sound is output. Therefore, an empty signal E is output for each channel, and since no key has been pressed yet at this time, the key-on signal KO is not output, and the AND gate 23 is open. A rewriting signal ψ0 is output for each channel, and the latch 31 of the channel allocation section 12 successively stores the channel value C.
“-11”J will be rewritten.

When a key on the keyboard 1 is operated, the key operation detection unit 2 sends a key-on signal K having a width equal to the key cycle.
Since O outputs, KO=0, and dart 23
Since latch 3 is closed, from now on, the channel period is as follows: latch 3
1 holds the channel value ah immediately before the output of the key-on signal KO.

Then, when the value of the output channel matches the channel value in the latch 31, the 11" signal is output from the NOR gate 33. At this time, the key-on signal KO is still output, and the empty signal E is output again when this channel is output. Therefore, the channel assignment signal KO1 is output.In this case, the AND gate 23 is closed during the channel period and the rewriting signal ψ0 is not output. The contents of the latch 31 will not be rewritten while the search is being performed until it matches the channel value of .

Then, the channel indexing signal KOI is given to the key code memory 3 and the envelope control unit 6, and the key code of the operation key is input to the specified channel, and an envelope signal whose value changes with time As a result, the musical sound waveform is generated by the wave generation section 4, envelope-controlled by the multiplication section 5, and then the musical sound is emitted from the speaker via the accumulating section 7, etc. be done.

In this way, as the number of pressed keys is increased sequentially, musical tones are assigned to empty channels one after another in the same way. At this time, since the empty signal E, key-off attenuation signal KF, and key-on attenuation signal RO are not output from the assigned channels, there is no possibility that musical tones will be assigned twice to the same channel.

Then, when eight keys are pressed on the keyboard 1 and musical tones are assigned to all channels, there are no empty channels.

After that, when the designated channel becomes 0 and the AND gate 27 of the hold circuit 22 of the channel search section 110 is closed, the contents of the latch 26 are cleared when the next channel no. 4 pulse signal ψ is output. This state is maintained until the AND gate 29 is opened and a channel to which a new musical tone can be assigned appears. That is, after the channel is 00, it is incremented as 1.2... and the AND gate 27 is opened. , the AND gate 23 does not output a 1" signal, and the launch 26 holds "O".

Then, while pressing the keys like a piano sound, the envelope 7' waveform Z (FIJ-) will be played, and if the upper 3 bits of the envelope value are ``U00J'', for example, the 3rd channel will appear. Since the key-on attenuation signal RO is output from the envelope control section 6, the OR gate 30, AND gate 29, OR gate 21, and
ff-) 23 outputs "1" signal tube, and the channel no? in the next third channel is output. When the pulse ψ is output, the rewrite signal ψ〇17- is output, and the content of the latch 26 also becomes "1".

As a result, the latch 31 of the channel dividing part 12
The value "011(3)J" of the third channel is latched, and the envelope value EC is latched in the latch 14 of the channel search unit 11. At this time, RO=0, KF
= 1, the actual envelope value EC is “00
Even if it is "0", "100" will be latched in the latch 14.

In addition, since the latch 26 of the hold circuit 22 becomes "1", the AND dart 27 outputs "1" and the AND dart 29 is closed, so that from then on, until the θ channel becomes available again, The key-on attenuation signal RO and the key-off attenuation signal KF are not accepted after the third channel. In this way, whenever the envelope value to be compared is latched in the latch 14, an envelope value EC smaller than the envelope value "100" input to the latch 14 is given, and the or-dart 218 of the comparison circuit 15 is - If 0 is output or the empty signal E is not given, the rewrite signal ψ0 will not be output, and the channel assignment unit 120 launch 3 will not be rewritten.

Then, if roll (3) J is latched in the ratte 31 and the 9th key is pressed, the key-on signal KO will be output for one cycle in the same way as described above.
When the AND gate 23 is closed and the value of the latch 31 is held for one cycle, and the designated channel becomes 3, the Noah Dart 33 outputs a match signal, and at that time the key-on signal K
O is output and the key-on attenuation signal RO is output again on channel 3, so the channel assignment signal is AND dirt 3.
4, and the tone of the ninth key is newly assigned to channel 3. In this way, even if the musical tone currently being pressed is assigned to all channels, if there is a decaying channel whose upper envelope value is "000", a new musical tone is assigned.

In addition, when assigning a new channel to a pressed key, for example, in channel 3 as described above, the key is being pressed and is attenuating, and the latch 31 is set to "011(3)" and the latch 14 is set to [011(3)].
100J is latched and, for example, in channel 4, the key associated with the assigned musical tone is released and the musical tone is attenuated, and the key-off attenuation signal KF is detected by the key operation detection unit 2.
, and if the top three pits of the envelope ff1Ec at that time are less than ``o11J'', then of course all other channels are held down and the envelope is larger than the above three channels, then the fourth channel is KF.
= 0, so just and dart] 3m to 13.
is compared with the value in latch 14 via . Then, the most significant bit indicates that the output of the latch 14 is r'IJ, and the OR gate 13 . Since the output of is "0", it is AND GO) 19
．． outputs "1", AND gate 2o outputs "]", and AND dart 23 outputs "1" via Oake"-1.21, so rewrite signal φ0 is output [2, The channel value rxoo(4)J is latched to the latch 31, and the envelope value r011J is latched to the latch 14. Therefore, an instruction is given to allocate a new key-pressed musical tone to the fourth channel.

If a musical tone is assigned between the 5th channel and the 7th channel, and the tone is being sounded attenuated after the key is released, and there is a channel whose envelope value is even smaller than the above "011", the OR gate 20 will output the "1# signal". and output the rewrite signal ψ
0 is output, and its channel value ah and envelope value are latched in the latch 31 and latch 14.

Furthermore, if there is an empty channel after that, or gate 2
1 is output and the rewrite signal ψ. outputs, and in the same way, the value ah of that empty channel and the envelope value 1”-000
J is latched.

Also, roll is applied to latch 31 on specified channel 3 mentioned above.
(3) Even if J outputs the key-off attenuation signal KF in another channel after 100J is latched, the contents of latch 31.14 are It remains as it is.

In this way, after channel 0, if a channel with better conditions appears compared to the channels that can be assigned, the search assignment channel is changed to one with better conditions, and eventually an empty channel and a key-off decaying channel appear. Channels where the upper envelope value is ro 11J or less, channels where the upper envelope value is roooJ during key-on, and r when the upper envelope value is at key-off
Channel search and assignment is performed in priority order of channels of l00J or higher. In this case, if all channels are occupied, the empty signal E, key-off attenuation signal KF, and key-on attenuation signal RO are not output, and no channel assignment is made.

Then, when the output channel becomes 0 again, latch 2
6 is cleared and the AND/DART 29 is opened, and the same operation is repeated until the key-on signal KO is output, and the channel value ch most suitable for assignment is latched in the latch 31. In this way, the assigned channel is searched in advance in preparation for the next key press, and according to the new key press, the channel specified by the latch 31 is assigned.
Of course, the channel is an empty channel or the key pressed 22.
- Or, the musical tone is controlled to be assigned only when the key is in the attenuated state while the key is being released.

[Second Embodiment] FIG. 4 shows a specific circuit configuration diagram of the channel allocation section 12 of the second embodiment, and since the other configuration of the second embodiment is the same as the first embodiment, Explanation will be omitted. 1st above
In the embodiment, the channel value of the latch 310 of the channel assignment unit 12 is not rewritten during the one-cylinder period in which the key-on signal KO is output, and therefore the new key assignment is performed at least within one cycle of all channels from the previous assignment. This could not be done until later, but in the second embodiment, by providing two latches, channel value rewriting and channel assignment are performed alternately in each channel cycle, and channel value rewriting can be performed even when a key-on signal is output. This made it possible.

Channel search unit 1 ``The output rewriting signal ψ is input to AND gates 36 and 37, respectively, and the AND gate 36 is given the output of the latch 38 to open and close. controlled and dirt 3
7, the output of the latch 38 is applied as an inverted output via an inverter 39, and is similarly controlled to open and close. The output of the inverter 39 is fed back into the latch 38, and each time the output channel becomes 0, the output of the inverter 39 is taken in and latched when the output signal ψ6 is output. Therefore, the contents of the latch 38 are inverted every channel cycle, and the contents of the latch 38 are
．． 37 are opened alternately every channel-period.

This AND GO) 36.37 output signal ψ. 1, ψ. ,
are the first latch 40 and the second latch 41 of 3 bits, respectively.
is given as a latch signal to “000(0)J to r
The three-pit channel values ah up to ill(7)J are captured and latched.

The outputs of each bit of the first latch 40 and the second latch 41 are transferred to transfer darts 421 to 425 and 431 to 43.
．． 44°44. This transfer gate 42. ~42. , the inverted output of the latch 38 via the inverter 39 is transferred to the other transfer circuit (431 to 43.). The above latch 3
The output of No. 8 is given as is as an opening/closing control signal.

Therefore, the AND gate 36 is opened and the signal ψ is output. When 1 is output, the transfer dart is 43° to 43. is opened, and on the other hand, the AND dart 37 is opened and the signal ψ is opened.

, when the transfer gates 421 to 42 .
will be opened. , the exclusive or gate 44. ~44
．． , each bit value of the channel value ah is also input as is, and each output of the exclusive OR gates 441 to 443 is input to the nordart 45.

The output of this NOR gate 45 is input to an AND dart 46, and this AND gate 46 receives the key-on signal K.
O is also input, and the output of the or-dirt 47 to which the empty signal E, key-off attenuation signal KF and key-on attenuation signal RO is input is also input, and the output of the and-dirt 46 is sent to the key code memory 3 and the envelope as the channel side vortex signal KO1. 25- In place of KO, channel search section 11's AND? −)
23 and is inverted and input.

Next, the operation of the channel allocation section 12 of this embodiment will be explained.

Now, assuming that the content of the latch 38 is "1", the AND gate 36 and ;・Runsno dart 43, ~43
1 is opened. Then, when a channel that can be assigned is searched and the channel search unit 11 outputs the rewrite signal ψ0, the AND gate outputs the signal ψ01 and the first latch 40 receives the current output channel value a.
h is latched.

Thereafter, when the channel period period elapses and the content of the latch 38 is inverted from "1" to "0", the AND dart 37
And transfer gates 421 to 42.0 are opened. Then, when the rewriting signal ψ0 is input this time, the signal ψ0! Since the channel value ch is outputted, the channel value ch is latch 26 to the second latch 41. If the channel value Ch input during this channel period and the channel value h latched in the first latch 40 match, the NOR gate 45 outputs.

If the key-on signal KO is applied during this time, the AND gate 46 is opened, and the channel assignment signal KOI is output and channel assignment is performed. At the same time, even if this key-on signal KO is given, the AND gate 23 of the channel search section 11 is oxidized and therefore,
The aforementioned latching of the channel value ah into the second latch 41 continues without being stopped.

In this way, while one latch is specifying the channel to be actually allocated, the other latch is latching the channel value to be allocated next, so there is an advantage that channel allocation can be performed one after another.

〔Effect of the invention〕

As described above, according to the present invention, a new sound is assigned and produced even in a channel to which a note is being attenuated while a key is being pressed, so that channel assignment can be done efficiently without waste. In addition, channels are assigned with priority given to empty channels, and envelope values are compared and assignments are made to channels with smaller envelope values, so channels can be used more effectively. play.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is an overall block circuit diagram, and FIG. 2 is a channel search unit 11.
3 is a circuit diagram of the channel allocation section 12, and FIG. 4 is a circuit diagram of the channel allocation section 12 of the second embodiment. 11...Channel search section, 12...
Channel allocation section, 14... Latch, 15...
... Comparison circuit, 22 ... Hold circuit, 3
1... Latch, 40... First latch,
41...Second latch. Patent applicant Casio Computer Co., Ltd. agent Patent attorney Hajiko Yamada'

Claims (2)

[Claims] (1) In a polyphonic electronic musical instrument in which the envelope of an output musical sound gradually attenuates even when a key is pressed, a first means for detecting an empty channel that is not in a sound generation state among a plurality of musical sound generation channels; a second means for detecting a channel among the musical sound generation channels in which the key is being released and whose envelope is attenuated the most; A third channel that detects the channel whose envelope is attenuated the most among the plurality of musical tone generation channels when the key is being pressed.
and determining each channel detected by the first, second, and third means as a channel to which a musical tone corresponding to a new key depression is to be assigned, using different priority conditions;
A channel allocation device for an electronic musical instrument, comprising an allocation means for allocating musical tones to skeleton sound generation channels. (2) When the above-mentioned allocation means assigns the channel detected by the above-mentioned first means as the highest priority allocation channel, and each channel detected by the second and third means has the same level of energy ff, 2. The channel assignment device for an electronic musical instrument according to claim 1, wherein the channel detected by the second means is preferentially assigned as the assigned channel.