Abstract:
The present invention provides touch sensor means for detecting the touch location along the length of an outfitted piano key as it is pressed, so as to then offset the notes of an associated piano keyboard accordingly during play. When such an outfitted key is pressed in combination with other piano keys, the touch location along the length of the outfitted key, and the separation intervals and timing of the key presses, are analyzed to determine the intended chord, such that before any notes are sounded, the notes of the pressed keys are configured for the sounding of that chord. This arrangement enables playing a wide range of notes using just a few keys, so as to provide a substantially reduced-size keyboard with full-sized keys sufficient for real-time playing. This arrangement also enables configuring the note offsets of those pressed keys to conform to a selected musical key, so as to simplify the layout of the keyboard by eliminating its black keys, while still supporting the playing of non-conforming notes. This arrangement further enables applying pitch variation to those note offsets in order to emulate the “string stretching,” “whammy bar,” and “fretless neck” playing techniques for guitars and basses. This arrangement even further enables playing advanced chords in a simplified manner. Finally, this arrangement enables providing a wide assortment of keyboards that can differ in the type, number, size, and functionality of their outfitted keys.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 14/224,625, filed Mar. 25, 2014, which was a division of U.S. patent application Ser. No. 13/491,045, now U.S. Pat. No. 8,710,344, filed Jun. 7, 2012. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention is directed toward a keyboard with touch sensors for detecting the touch location along the length of an outfitted key as it is being pressed, so as to thereby enable the functionality of the keyboard to be continually reconfigured during play in accordance with the touch location being detected. This reconfiguration can be utilized to enhance that functionality, simplify its use, and substantially reduce the number of keys and keyboard footprint required for its implementation. Such touch detection is particularly applicable to touchscreen, piano-type keyboards; however, it is generally applicable to any keyboard being associated with electronic control, especially where portability is an issue. 
     There are numerous piano keyboard apps available for iPads, and similar touchscreen devices. The popularity of these apps can be attributed, at least in part, to the portability of those tablets; however, due to the tiny size of their playing surface as compared to a standard piano keyboard, the number of keys available for playing at any given time, is extremely limited, which presents a serious obstruction to the playing of even the simplest piano arrangements. 
     In an attempt to alleviate this functionality obstruction, apps have typically: reduced key width to display additional keys; reduced key length to display multiple key rows; and provided keyboard repositioning swipes during play for revealing normally off-screen keys. While these measures do increase the number of readily available keys, the reduced key size and additionally required swipes have rendered such apps virtually unusable for real-time play. 
     Furthermore, since playing even simple arrangements requires a fair amount of skill, keyboards provide preprogrammed buttons for simulating actual playing. While such button pressing does enable beginners to circumvent this learning curve, because it is so far removed from the skills required for piano playing, very little learning is actually accomplished. A keyboard that offered skill simplification rather than complete elimination would be far more advantageous. 
     For example, consider the learning curve required for the playing of close, root-position chords, which is relatively small compared to that of advanced chord inversion and voicing. Suppose it were possible to play a close, root-position chord, but then configure the keyboard during play to automatically substitute an advanced chord inversion or voicing before any notes are sounded. This would substantially reduce the learning curve required for advanced playing, but would, at the same time, promote the learning of the basic playing skills. 
     To date, there is no such reconfigurable, piano-type keyboard that offers both full functionality and simplified playing, and especially not at a substantially reduced size. As such, there is a recognized need for a tablet-sized, piano-type keyboard, of either the touchscreen or physical variety, that can be continually reconfigured during play, so as to provide such capabilities. 
     SUMMARY OF THE INVENTION 
     The present invention provides touch sensor means for detecting the touch location along the length of an outfitted piano key as it is pressed, so as to then offset the notes of an associated piano keyboard accordingly during play. When such an outfitted key is pressed in combination with other piano keys, the touch location along the length of the outfitted key, and the separation intervals and timing of the key presses, are analyzed to determine the intended chord, such that before any notes are sounded, the notes of the pressed keys are configured for the sounding of that chord. This arrangement enables playing a wide range of notes using just a few keys, so as to provide a substantially reduced-size keyboard with full-sized keys sufficient for real-time playing. This arrangement also enables configuring the note offsets of those pressed keys to conform to a selected musical key, so as to simplify the layout of the keyboard by eliminating its black keys, while still supporting the playing of non-conforming notes. This arrangement further enables applying pitch variation to those note offsets in order to emulate the “string stretching,” “whammy bar,” and “fretless neck” playing techniques for guitars and basses. This arrangement even further enables playing advanced chords in a simplified manner. Finally, this arrangement enables providing a wide assortment of keyboards that can differ in the type, number, size, and functionality of their outfitted keys. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For the purpose of illustrating this invention, there are shown in the accompanying drawings forms that are presently preferred; it being understood that the invention is not intended to be limited to the precise arrangements and instrumentalities shown. 
         FIG. 1  is a top view of a first operational state of a first embodiment of an iPad, piano-type, touchscreen keyboard; 
         FIG. 2  is a top view of a second operational state of the first keyboard embodiment shown in  FIG. 1 ; and 
         FIG. 3  is a top view of a third and fourth operational state of the first keyboard embodiment shown in  FIGS. 1 and 2 . 
         FIG. 4  is a logic diagram of the first keyboard embodiment shown in  FIGS. 1 to 3 . 
         FIG. 5  is a top view of a second embodiment of an iPad, piano-type, touchscreen keyboard. 
         FIG. 6  is a top view of a third embodiment of an iPad, piano-type, touchscreen keyboard. 
         FIG. 7  is a top view of a fourth embodiment of an iPad, piano-type, touchscreen keyboard. 
         FIG. 8  is a top view of a first operational state of a fifth embodiment of an iPad, piano-type, touchscreen keyboard; 
         FIG. 9  is a top view of a second operational state of the fifth keyboard embodiment shown in  FIG. 8 ; 
         FIG. 10  is a top view of a third operational state of the fifth keyboard embodiment shown in  FIGS. 8 and 9 ; 
         FIG. 11  is a top view of a fourth operational state of the fifth keyboard embodiment shown in  FIGS. 8 to 10 ; 
         FIG. 12  is a top view of a fifth operational state of the fifth keyboard embodiment shown in  FIGS. 8 to 11 ; and 
         FIG. 13  is a top view of a sixth operational state of the fifth keyboard embodiment shown in  FIGS. 8 to 12 . 
         FIG. 14  is a top view of a sixth embodiment of an iPad, piano-type, touchscreen keyboard. 
         FIG. 15  is a top view of a seventh embodiment of an iPad, piano-type, touchscreen keyboard. 
         FIG. 16  is a logic diagram of the fifth keyboard embodiment shown in  FIGS. 8 to 13 . 
         FIG. 17  is a logic diagram of the sixth keyboard embodiment shown in  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings in detail, like reference numerals have been used throughout the various figures to designate like elements. 
     A first embodiment of an iPad, piano-type, touchscreen keyboard of the invention is shown in  FIGS. 1, 2, and 3 , and is designated generally as  300 . This keyboard  300  is comprised of 7, piano-sized, white keys  120 ,  122 ,  124 ,  126 ,  128 ,  130 , and  132  arranged across the full portrait screen width. The first white key  120  is divided lengthwise into 15 sections  340 ,  342 ,  344 ,  346 ,  348 ,  350 ,  352 ,  354 ,  356 ,  358 ,  360 ,  362 ,  364 ,  366 , and  368 . The corresponding notes  370 ,  372 ,  374 ,  376 ,  378 ,  380 ,  382 ,  384 ,  386 ,  388 ,  390 ,  392 ,  394 ,  396 , and  398 , respectively, played by touching those sections are set to the first 15 notes (C3-D-E-F-G-A-B-C4-D-E-F-G-A-B-C5) of the 3-octave note sequence C3-D-E-F-G-A-B-C4-D-E-F-G-A-B-C5-D-E-F-G-A-B of the C Major scale, those 15 notes being initially centered around middle C (C4), so as to currently have a center octave of 4. 
     When the first white key  120  is pressed from one of its sections  340 ,  342 ,  344 ,  346 ,  348 ,  350 ,  352 ,  354 ,  356 ,  358 ,  360 ,  362 ,  364 ,  366 , or  368 , the remaining white keys  122 ,  124 ,  126 ,  128 ,  130 , and  132  will be reconfigured in correspondence with a span of 7 white keys on a standard piano keyboard starting with the note  370 ,  372 ,  374 ,  376 ,  378 ,  380 ,  382 ,  384 ,  386 ,  388 ,  390 ,  392 ,  394 ,  396 , or  398  associated with that touched section  340 ,  342 ,  344 ,  346 ,  348 ,  350 ,  352 ,  354 ,  356 ,  358 ,  360 ,  362 ,  364 ,  366 , or  368 . As such, if the first white key  120  is progressively pressed from its first section  340  to its last section  368 , the corresponding notes of the 7 keys  120 ,  122 ,  124 ,  126 ,  128 ,  130 , and  132  will progress from C3-D-E-F-G-A-B to C5-D-E-F-G-A-B. 
     In this manner, with just 7 white keys, a 3-octave keyboard can be implemented in a footprint the size of an iPad screen, while retaining the full key size and basic functionality of a standard piano keyboard, as well as enabling all chords to start from the same key, so as to simplify their playing. This keyboard can also be configured to substitute a chord inversion or alternate chord voicing when a standard, root-position chord is pressed, so as to further simplify the playing of chords. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
       FIG. 1  shows a first operational state of the above keyboard  300 . As such, the corresponding notes  384 ,  322 ,  324 ,  326 ,  328 ,  330 ,  332  played by the touching of the 7 white keys  120 ,  122 ,  124 ,  126 ,  128 ,  130 , and  132 , respectively, are set to the note sequence C4-D-E-F-G-A-B from the above 3-octave note sequence, starting with the note ‘C4’  384  associated with the initially last touched section  354  of the first white key  120 . 
       FIG. 2  shows a second operational state of the above keyboard  300 . As such, the touching of section  362  accordingly shifts the corresponding notes  392 ,  322 ,  324 ,  326 ,  328 ,  330 , and  332  played by the touching of the 7 white keys  120 ,  122 ,  124 ,  126 ,  128 ,  130 , and  132 , respectively, to the note sequence G-A-B-C5-D-E-F from the above 3-octave note sequence, starting with the note ‘G4’ 392 of the currently touched section  362  of the first white key  120 . 
       FIG. 2  also shows that the keyboard  300  is further comprised of a pop-up data picker  310  with a control wheel  312  to select the current center octave (4)  314 , and another control wheel  316  to select the current musical key (C Major)  318 . This combination is used to determine the scale and octave range of the above 3-octave note sequence. 
       FIG. 3  shows a third operational state of the above keyboard  300  corresponding to an initial center octave of 4 and musical key of C Major. As such, the combination of the 3 touched keys  120 ,  124 , and  128  respectively plays the corresponding notes ‘A#3’ 382, ‘D4’ 324, and ‘F4’ 328, where the first note (A#3)  382  does not conform to the current musical key of C Major, but has been programmed to replace the conforming note (B3) normally played by the section  352 , so as to enable, in a limited fashion, the playing of notes outside the set of notes conforming to the current center octave and musical key, while using the same keyboard keys that would normally play only conforming notes. 
       FIG. 3  also shows a fourth operational state of the above keyboard  300 . As shown in the figure, there is a first touch position (p 1 )  334  along the length of the third white key  124 , a subsequent position deviation (Δρ)  336  to a second touch position (p 2 )  338  along that same key  124 , and a related frequency deviation (Δf)  320  in the pitch of the corresponding note  324  being played by that key  124 , where continued such position deviations will result in continued such frequency deviations for as long as the touching of the key  124  is maintained, thereby enabling emulation of the string stretching, whammy bar, and fretless neck techniques of guitar and bass playing. 
     A logic diagram for the above keyboard  300  is shown in  FIG. 4 , and is designated generally as  100 . The symbols used in this logic diagram  100  are further explained in the following chart. 
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
             
               
               
               
               
               
             
               
               
               
               
             
               
               
               
             
               
               
               
               
             
               
               
               
               
               
             
               
               
               
             
           
               
                   
               
             
             
               
                 Delay (from 7-Input OR): 
               
             
          
           
               
                 0 to 1  
                 =&gt; 1(Enable) -  
                 1-Line Logic 
                 Key: 
                   
               
             
          
           
               
                 after delay 
                 ----------------&gt; 
                 Pressed 
                  =&gt; Y, 
               
             
          
           
               
                 0  
                 =&gt; 0(Disable) - 
                   
                 1(Play), 1 
                   
               
             
          
           
               
                 immediately 
                 1-Line Data 
                 Released 
                 =&gt; OFF, 
               
               
                   
                 |---------------&gt; 
                 0(Stop), 0 
                   
               
             
          
           
               
                 Synth (from Key 0/1 
                 7-Line Logic 
                 Analyzer (from Key OFF/Y): 
               
             
          
           
               
                 AND Delay 0/1): 
                 
                           
                 
                 OFF to Y 
                  =&gt;  
               
             
          
           
               
                 0 to 1 
                 =&gt; Latch Note 
                 7-Line Data 
                 Y0=Y 
                   
               
               
                 1 
                 =&gt; Play Latched 
                 
                           
                 
                 Y  
                 =&gt; PC= 
               
               
                   
                 Note 
                   
                   
                 Y-Y0 
               
               
                 0 
                 =&gt; Stop Player 
                   
                 OFF 
                 =&gt; PC=0.00 
               
               
                 1 to 0 
                 =&gt; N/A 
                   
                 Key1:OFF to Y 
                  =&gt; 
               
             
          
           
               
                   
                   
                 Row=int(Y/m) 
               
               
                   
               
             
          
         
       
     
     The diagram  100  logic is preset for the musical key ‘Scale’ selector to output a value of ‘Major’, the musical key ‘Tonic’ selector to output a value of ‘C’, and the center ‘Octave’ selector to output a value of ‘4’, which presets the notes of row ‘r-8’, for columns ‘c-1’ through ‘c-7’, to the notes of the C Major key, beginning with note ‘C4’ (namely, C4, D4, E4, F4, G4, A4, and B4). Successive rows above and below r-8 are also preset with the notes of the C Major key, but starting at notes successively above and below ‘C4’, respectively. The note ‘Offset’ selector is initially set to modify the note at ‘r-8’/‘c-7’ by +1 semitone to ‘C5’, and the note at ‘r-7’/‘c-1’ by −1 semitone to ‘A#3’. This provides for the playing of custom chords arrangements, as well as for the playing of chords outside the C Major key, both of which would not otherwise be possible. 
     The initial ‘Row’ value being output from the ‘Analyzer’ is internally preset to ‘r-1’ and is not user selectable. This ‘Row’ value causes the notes of ‘r-1’ (namely, C3, D3, E3, F3, G3, A3, and B3), to be output to ‘Synth1’ through ‘Synth7’, respectively. 
     With “no keys being initially pressed” as the starting condition, ‘Key1’ 120 through ‘Key7’ 132 each outputs a value of ‘Stop’ (logical 0) to ‘Synth1’ through ‘Synth7’, respectively, a value of logical 0 to the 7-input ‘OR’, and a ‘Y’ value of ‘OFF’ to the ‘Analyzer’. As a result, the output of the 7-input ‘OR’ is set to a value of logical 0, and the output of the rising edge ‘Delay’ is set to a value of ‘Disable’ (logical 0) for the 7 synths, all of which are stopped and disabled from playing due to the values of ‘Stop’ and ‘Disable’ being input. 
     Pressing ‘Key3’ 124 causes it to then output a value of ‘Play’ (logical 1) to Synth3′, which is currently loaded with a ‘Note’ of value ‘E3’, but it is also disabled, so it does not yet start playing. The ‘Key3’ 124 press also causes it to output a value of logical 1 to the 7-input ‘OR’, and to output the ‘Y’ value of the pressed point along that key to the ‘Analyzer’, which then internally latches the ‘Y’ value as the ‘Y0’ of ‘Key3’ 124, for comparison with future ‘Y’ values from ‘Key3’ 124. Upon its logical 1 input, the 7-input ‘OR’ outputs a value of logical 1, which triggers the rising edge ‘Delay’ to output a value of ‘Enable’ (logical 1) after a brief delay. 
     Additionally pressing ‘Key5’ 128 and ‘Key7’ 132 within the delay time interval causes each key to output a value of ‘Play’ to ‘Synth5’ and ‘Synth7’, respectively, each of which is currently loaded with a ‘Note’ of value ‘G3’ and ‘B3’, respectively, but they are also both disabled, so they do not yet start playing. The ‘Key5’ 128 and ‘Key7’ 132 presses also cause each key to output a value of logical 1 to the 7-input ‘OR’, and to additionally output the ‘Y’ value of its press to the ‘Analyzer’, which then internally latches that ‘Y’ value as the ‘Y0’ of that key, for comparison with future ‘Y’ values from that key. 
     If no other keys are pressed before the delay time interval has expired, upon expiration of such, the rising edge ‘Delay’ outputs a value of ‘Enable’ to each synth, which triggers the immediate latching and start of playing of notes ‘E3’, ‘G3’, and ‘B3’ corresponding to ‘Synth3’, ‘Synth5’, and ‘Synth7’, respectively, since those are the only synths inputting a ‘Play’ value from their corresponding key. This effectively plays an E minor chord. 
     Alternatively, if the pressing of ‘Key1’ 120 (at a ‘Y’ value corresponding to ‘r-8’) also occurs before the delay time interval has expired, this causes ‘Key1’  120  to output a value of ‘Play’ to ‘Synth1’, which is currently loaded with a ‘Note’ of value ‘C3’, but it is also disabled, so it does not yet start playing. The ‘Key1’  120  press also causes the key to output a value of logical 1 to the 7-input ‘OR’, and to output the ‘Y’ value of its press to the ‘Analyzer’, which internally latches that ‘Y’ value as the ‘Y0’ of that key, for comparison with future ‘Y’ values from that key, and which then outputs a ‘Row’ value of ‘r-8’ based on the ‘Y’ value output by ‘Key1’ 120. The ‘Row’ value ‘r-8’ causes notes ‘C4’, ‘D4’, ‘E4’, ‘F4’, ‘G4’, ‘A4’, and ‘C5’ to be output to ‘Synth1’ through ‘Synth7’, respectively, which are all disabled, so no playing occurs. Once the delay time interval has expired, the rising edge ‘Delay’ outputs a value of ‘Enable’ to all synths, which then triggers the immediate latching and start of playing of the notes ‘C4’, ‘E4’, ‘G4’, and ‘C5’ corresponding to ‘Synth1’, ‘Synth3’, ‘Synth5’, and ‘Synth7’, respectively, since those are the only synths inputting a ‘Play’ value from their corresponding key. This effectively plays a C Major chord, with a root note of C4, and a doubling of the root note at C5. 
     While a key is being pressed, the ‘Y’ value of the pressed point along the key is continually updated and output to the ‘Analyzer’, where it is compared with the ‘Y0’ value latched for that key when it was initially pressed, and a ‘Pitch Control’ value ‘Y-Y0’ is output to the corresponding synth to control its pitch, thus providing a pitch modulation effect, similar to that of a guitar string bend, string slide, or whammy bar, which can be accomplished simply by sliding one&#39;s finger up and down along the key being pressed with that finger. 
     When a key is released (possibly ‘Key1’  120 ), the output to its corresponding synth is set to a value of ‘Stop, and if any key remains pressed, such that the 7-input ‘OR’ output is still set to logical 1, and the rising edge ‘Delay’ output is still set to ‘Enable’, thereby causing all synths to remain enabled, and playing if their corresponding key is pressed, then the synth corresponding to the released key is immediately stopped from playing. Further, the ‘Y’ output of the released key going to the ‘Analyzer’ is set to ‘OFF’. If the released key is, in fact, ‘Key1’, the Y0 value for ‘Key1’ remains latched internally to the ‘Analyzer’, so the ‘Row’ output from the ‘Analyzer’ remains unchanged. 
     If a new key (other than ‘Key1’ 120) is pressed before all keys have been released, such that the 7-input ‘OR’ output is still set to logical 1 and the rising edge ‘Delay’ output is still set to ‘Enable’, then the output to its corresponding synth is set to a value of ‘Play’, and its output to the 7-input ‘OR’ is set to a logical 1, which causes the synth to latch and start playing the ‘Note’ corresponding to the newly pressed key, as determined by the current ‘Row’ value from the ‘Analyzer’, and by the column assignment of the pressed key. 
     If ‘Key1’  120  had been released, and is newly pressed (at a ‘Y’ value corresponding to ‘r-3’) before all keys have been released, such that the 7-input ‘OR’ output is still set to logical 1, and the rising edge ‘Delay’ output is still set to ‘Enabled’, that ‘Y’ value is output to the ‘Analyzer’, where it is internally latched as the ‘Y0’ of ‘Key1’, for comparison with future ‘Y’ values from ‘Key1’  120 . At this same time, the ‘Analyzer’ outputs the corresponding ‘Row’ value of ‘r-3’, thereby causing that row of notes ‘E3’, ‘F3’, ‘G3’, ‘A3’, ‘B3’, ‘C4’, and ‘D4’ to be output to ‘Synth1’ through ‘Synth7’, respectively, immediately after which the ‘Key1’  120  output to the already enabled ‘Synth1’ is set to a value of ‘Play’, thus causing ‘Synth1’ to latch its loaded ‘Note’ of value ‘E3’ and start playing it. The remaining synths whose corresponding keys are pressed, namely, ‘Synth3’, ‘Synth5’, and ‘Synth7’, continue playing their previously latched notes. 
     The ‘Row’ value of ‘r-3’ remains in effect until the next new ‘Key1’  120  press. Thus, by newly pressing the same keys as before, namely, ‘Key1’ 120 (but now at a new ‘Y’ value corresponding to ‘r-3’, rather than ‘r-8’), ‘Key3’  124 , ‘Key5’  128 , and ‘Key7’  132 , what previously played a modified C Major chord, now plays an E minor 7th. 
     When all keys have been released, the outputs of ‘Key1’  120  through ‘Key7’  132 , being input to ‘Synth1’ through ‘Synth7’, respectively, are reset to a value of ‘Stop’, which stops from playing any synth that had been playing just prior to the release, and the ‘Y’ outputs of ‘Key1’  120  through ‘Key7’  132 , being input to the ‘Analyzer’, are reset to OFF, which then leaves the ‘Row’ output of the ‘Analyzer’ unchanged, such that subsequent key presses would be evaluated by restarting this logic from the “no keys being initially pressed” condition, but now beginning with the current ‘Row’ value being output from the ‘Analyzer’. 
     A second embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIG. 5 , and is designated generally as  400 . This keyboard  400  has attributes nearly identical to those of the above keyboard  300  in  FIGS. 1, 2, and 3 ; however, it is comprised of  11 , non-sectioned, black and white keys  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 ,  434 ,  436 ,  438 , and  440  in place of the 6 such white keys  322 ,  324 ,  326 ,  328 ,  330 , and  332  of the above keyboard  300 . 
     The  11  black and white keys  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 ,  434 ,  436 ,  438 , and  440  are equal to the length and 6/11 the width of the above replaced white keys  322 ,  324 ,  326 ,  328 ,  330 , and  332  in  FIGS. 1, 2, and 3 . The 11 black and white keys  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 ,  434 ,  436 ,  438 , and  440  are further color coordinated with the 11 black and white keys immediately following a C-key on a standard piano keyboard. As such, the operation of the first white key  120  and of the pop-up data picker  310  are as described for the above keyboard  300 , and the corresponding notes  384 ,  450 ,  452 ,  454 ,  456 ,  458 ,  460 ,  462 ,  464 ,  466 ,  468 , and  470  of the total of 12 black and white keys  120 ,  420 ,  422 ,  424 ,  426 ,  428 ,  430 ,  432 ,  434 ,  436 ,  438 , and  440  are the 12-note sequence of notes (C4-C#-D-D#-E-F-F#-G-G#-A-A#-B) on a standard piano keyboard starting with the note (C4)  384  of the last touched section  354  of the first white key  120 . 
     In this manner, with just a single octave of keys, a 3-octave keyboard can be implemented in a footprint the size of an iPad screen, while retaining the full key size and basic functionality of a standard piano keyboard, and enabling all chords of a specific chord type, regardless of their root note, to be played using just the finger position of a C-chord of that chord type, thereby greatly simplifying all chord playing. This keyboard can also be configured to substitute a chord inversion or alternate chord voicing when a standard, root-position chord is pressed, so as to further simplify the playing of chords. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
     A third embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIG. 6 , and is designated generally as  500 . This keyboard  500  is comprised of a combination of 25, piano-sized, black and white keys  501  to  525 , arranged in a layout typical of the two-octave span of keys centered around middle C (C4) on a standard piano. The keys  501  to  525  are each divided lengthwise into three touch sensor bands  531  to  533  that span the full width of the keyboard  500 , such that, when the keys  501  to  525  are progressively pressed from a touch point within their middle band  532 , their corresponding notes will range from C3 to C5, respectively; however, when the keys  501  to  525  are so pressed from a touch point within their bottom band  531  or top band  533 , their corresponding notes will range from C2 to C4 or C4 to C6, respectively. 
     In this manner, using 2 octaves of keys, a 4-octave keyboard can be implemented in a footprint the size of an iPad Pro screen, while retaining the full key size and much of the functionality and the playability of a standard piano keyboard. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
     A fourth embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIG. 7 , and is designated generally as  600 . In a manner very similar to the above keyboard  500  in  FIG. 6 , this keyboard  600  is comprised of a two-octave span of 25 keys  501  to  525 ; however, instead of the three touch sensor bands  531  to  533  of the above keyboard  500 , the keys  501  to  525  are divided lengthwise into seven, more narrow, touch sensor bands  631  to  637  that operate similarly to the three touch sensor bands  531  to  533 , so as to determine the octave of the corresponding note that is played whenever a key is pressed from a specific band. 
     However, playing a chord or arpeggio would be very difficult if all keys in such a series had to be pressed from within a single narrow band. Therefore, whenever such a series of key presses is initiated, the first band that is touched remains in effect until all the keys  501  to  525  have been released and remain so for a brief period of time, typically on the order of 0.1 to 0.5 seconds, so that all notes in a given series, regardless of from which of the touch sensor bands  631  to  637  they were pressed, can be played with the same band in effect, and when a new series of key presses is initiated, another of the touch sensor bands  631  to  637  can take effect. 
     In this manner, again using 2 octaves of keys, an 8-octave keyboard can now be implemented in a footprint the size of an iPad Pro screen, while retaining the full key size, and virtually all of the functionality and playability, of a standard piano keyboard, but now, with an even wider note span (97 notes vs. 88 notes) than that of a piano. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
     A fifth embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIGS. 8 to 13 , and is designated generally as  700 . This keyboard  700  is comprised of a combination of 17, piano-sized, black and white keys  701  to  717 , being arranged in a layout typical of a 17-key span starting from any C key on a standard piano. Two white keys  701  and  713  are respectively outfitted with GUI radio button assemblies  720  and  750 , each respectively sectioned lengthwise into  22 , mutually exclusive (in radio button fashion), touch sensors  721  to  742  and  751  to  772 . These two radio button assemblies  720  and  750  are themselves mutually exclusive, such that there can be only one touch sensor  721  to  742  or  751  to  772  in effect at any given time. 
       FIG. 8  shows none of the keys  701  to  717  of the above keyboard  700  currently being pressed. As such, if either touch sensor outfitted key  701  or  713  were progressively pressed from within each of its touch sensors  721  to  742  or  751  to  772 , respectively, starting from its bottom touch sensor  721  or  751 , respectively, and progressing to its respective top touch sensor  742  or  772 , the respective corresponding notes for that key  701  or  713  would range from C2 to C5 or C3 to C6. Furthermore, each time a new touch sensor  721  to  742  or  751  to  772  comes into effect, the left touch sensor outfitted key  701  will be configured for that associated note, and the remaining keys  702  to  717  will be immediately reconfigured from that note in accordance with the notes of a standard piano. 
       FIG. 9  shows the left touch sensor outfitted key  701  being pressed from its C4 touch sensor  735  (as indicated by the highlighting of that key  701  and the unhighlighting of that touch sensor  735 ), which configures the corresponding note of the key  701  for C4 (as indicated by the display  780  at the top of the key  701 ), and reconfigures the corresponding notes of all keys  701  to  717  for the notes C4 to E5. This configuration remains in effect until the left touch sensor outfitted key  701  is released, and a different touch sensor  721  to  742  or  751  to  772  is subsequently pressed. 
       FIG. 10  shows a root position C Major chord being pressed (as indicated by the 3 highlighted keys  701 ,  705 , and  708 ). The left touch sensor outfitted key  701  is being pressed from its C4 touch sensor  735  (as indicated by that touch sensor  735  being unhighlighted), which configures the corresponding note of the key  701  for the chord root note C4, and respectively reconfigures the corresponding notes of the 2 remaining pressed keys  705  and  708  for the notes E4 and G4, being located a 3rd and 5th, respectively, above C4 (as respectively indicated by the 2 labels  781  and  783  at the top of those keys  705  and  708 ). 
       FIG. 11  shows the right touch sensor outfitted key  713  being pressed from its C5 touch sensor  765  (as indicated by the highlighting of that key  713  and the unhighlighting of that touch sensor  765 ), which configures the corresponding note of the key  713  for C5 (as indicated by the display  783  at the top of the key  713 ), and reconfigures the corresponding notes of all keys  701  to  717  for the notes C4 to E5. This configuration remains in effect until the right touch sensor outfitted key  713  is released, and a different touch sensor  721  to  742  or  751  to  772  is then subsequently pressed. 
       FIG. 12  shows a 1st inverted C Major chord being pressed (as indicated by the 3 highlighted keys  705 ,  708 , and  713 ). The right touch sensor outfitted key  713  is being pressed from its C5 touch sensor  765  (as indicated by that touch sensor  765  being unhighlighted), which configures the corresponding note of the key  713  for the 1st inverted chord root note C5, and respectively reconfigures the corresponding notes of the 2 remaining pressed keys  705  and  708  for the notes E4 and G4, being located a 3rd and 5th, respectively, above C4 (as respectively indicated by the 2 labels  781  and  783  at the top of those keys  705  and  708 ). 
       FIG. 13  shows a 2nd inverted C Major chord being pressed (as indicated by the 3 highlighted keys  708 ,  713 , and  717 ). The right touch sensor outfitted key  713  is being pressed from its C5 touch sensor  765  (as indicated by that touch sensor  765  being unhighlighted), which configures the corresponding note of the key  713  for the 2nd inverted chord root note C5, and respectively reconfigures the corresponding notes of the 2 remaining pressed keys  708  and  717  for the notes G4 and E5, located a 5th above C4 and a 3rd above C5, respectively (as respectively indicated by the 2 labels  781  and  783  at the top of those keys  708  and  717 , respectively). 
     As follows from the above discussions for  FIGS. 8 to 13 , with just 17 keys, a 53-note keyboard can be implemented in a footprint the size of an iPad Pro screen, while retaining the full key size and basic functionality of a standard piano keyboard, as well as enabling all chords of a specific chord type, regardless of their root notes, to be played using just the finger position of a C-chord of that chord type, and further enabling chord inversions to be based around their root notes, so as to substantially simplify all chord playing. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
     A sixth embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIG. 14 , and is designated generally as  800 . This keyboard  800  is virtually identical in both its form and function to the above keyboard  700  in  FIGS. 8 to 13 , except for the fact that two black keys  702  and  714  of this keyboard  800  are each sectioned lengthwise into 22 touch sensors  821  to  842  and  851  to  872 , respectively. The notes associated with each of the touch sensors  821  to  842  and  851  to  872  are respectively one semitone higher than the associated notes of the adjacent touch sensors  721  to  742  and  751  to  772  in  FIG. 14 , such that, if the two touch sensor outfitted black keys  702  and  714  were progressively pressed from within each of their touch sensors  821  to  842  and  851  to  872 , respectively, starting from their bottom touch sensors  821  and  851 , respectively, and progressing to their top touch sensors  842  and  872 , respectively, their corresponding notes would respectively range from C#2 to C#5 and C#3 to C#6. 
     In this manner, similar to the previously mentioned keyboard  700 , with just 17 piano-sized keys  701  to  717 , the 53-note span, C2 to E6, can be implemented in a footprint the size of an iPad Pro screen, while enabling all chords of a specific chord type, regardless of the chord root note, to be played with just a single finger position, namely, that of a C-chord of that type, which is even easier than on a standard piano keyboard. As would be obvious to one skilled in the art, many other configurations and footprints are possible. 
     Furthermore, in view of the additional touch sensor outfitted keys  702  and  714 , knowing the finger position for a relatively easily played chord having a natural root note (e.g., the C Major chord), makes it a simple matter to play the corresponding, more difficult to play, chord with its root note sharpened by one semitone (e.g., the C# Major chord), just by maintaining that finger position and shifting the entire playing hand one semitone to the right, which is exactly how it would be done on a standard piano. 
     A seventh embodiment of the above iPad, piano-type, touchscreen keyboard of the invention is shown in  FIG. 15 , and is designated generally as  900 . This keyboard  900  is virtually identical in both its form and function to the above keyboard  800  in  FIG. 14 , except for the fact that all keys  701  to  717  of this keyboard  900  are of both equal length and equal width. In view of this added keyboard  900  uniformity, the above mentioned one-semitone hand shifts would now be perfectly uniform transitions, regardless of the actual chord, which is even easier than can be done on a standard piano. 
     A logic diagram for the above keyboard  700  is shown in  FIG. 16 , and is designated generally as  1000 . This logic diagram  1000  uses black-filled arrow tips to designate logic flow along a single wire, and white-filled arrow tips to designate data flow along a multi-wire bus. To minimize the logic diagram  1000  complexity, some multi-function logic elements have been copied to multiple logic diagram  1000  locations, and such copies are indicated by their dashed border. To further minimize the logic diagram  1000  complexity, only five keys  701 ,  705 ,  708 ,  713 , and  717  of the keyboard  700  keys  701  to  717  are shown. The missing keys  702 ,  703 ,  704 ,  706 ,  707 ,  709 ,  710 ,  711 ,  712 ,  714 ,  715 , and  716 , as well as their connected logic circuits, are indicated by an ellipsis ( . . . ) placeholder between each of the shown keys  701 ,  705 ,  708 ,  713 , and  717 . Furthermore, for each of the touch sensor outfitted keys  701  and  713 , only three touch sensors,  721 ,  735 , and  742 , and  751 ,  765 , and  772 , respectively, of their total touch sensors  721  to  742  and  751  to  772 , respectively, are shown. 
     Whenever one of the keyboard  700  keys  701  to  717  is pressed, its corresponding note will play as configured according to which of the touch sensor sections  721  to  742  and  751  to  772  is in effect at that time. Whenever a chord is played, if its root note is played from the associated touch sensor  721  to  742  or  741  to  772  of a respective touch sensor outfitted key  701  or  713 , all keys  701  to  717  will then configured correctly for that chord. However, since all keys of a chord are not pressed at precisely the same time, it is likely that the touch sensor outfitted key  701  or  713  would not be the first chord key pressed, such that the actual, first-pressed chord key would then be incorrectly configured for the desired chord. 
     As such, if the first-pressed chord key were sounded with an incorrect corresponding note, and then, when a touch sensor outfitted key  701  or  713  is pressed, stopped and resounded with the correct corresponding note, noise will result. Furthermore, depending on the length of time the incorrect note has been sounded before being stopped, that noise could become objectionable. Therefore, it is necessary to delay the sounding of any pressed chord keys until a brief period of time after the first chord key has been pressed, thereby allowing enough time for all chord keys to become pressed in the normal playing of a chord, so that the pressed keys can be configured for the correct corresponding notes of that chord before they are sounded. 
     The problem with such a delay is that it will cause a lag in the note sounding, and depending on the magnitude of the delay time, the lag could become noticeable, and even more objectionable than the noise problem. Both of these problems are addressed in the following example. 
     Returning now to the logic diagram  1000 , suppose that the keyboard  700  is initially configured with the C4 (middle C) touch sensor  735  of the left touch sensor outfitted key  701  in effect. As such, the keyboard  700  keys  701  to  717  would be configured for the corresponding notes C4 to E5, respectively. 
     However, suppose it were now desired to play a C5 Major chord (C5-E5-G5). Since none of the keys  701  to  717  are currently configured for a corresponding note G5, the keyboard  700  would obviously have to be reconfigured to accommodate this new chord. Specifically, if the left touch sensor outfitted key  701  were now pressed from its C5 touch sensor  742 , so as to put that touch sensor  742  into effect, the keyboard  700  keys  701  to  717  would be configured for corresponding notes C5 to E6, respectively, and subsequent pressing of the E5 key  705  and G5 key  708  would complete the C5 Major chord. 
     Unfortunately, as discussed above, when playing a chord in the normal fashion, it is impossible to assure that the chord keys will be pressed in a particular order. In the above example, unless the left touch sensor outfitted key  701  is the first pressed, either of the other chord keys  705  or  708  being pressed first would sound their corresponding notes an octave lower than desired for a C5 Major chord. So, rather than sound the chord keys when pressed, a brief delay from the time of the first pressed chord key is needed to assure that all chord keys have been pressed before any corresponding notes are sounded, thereby allowing sufficient time for the keyboard  700  to be correctly configured for a C5 Major chord. 
     To implement this logic in logic diagram  1000 , the inputs of a 17-input OR gate  1040  are each connected to the output of one of the 17 keyboard  700  keys  701  to  717 , such that when the first key of the C5 Major chord is pressed, the output of that OR gate  1040  transitions from LOW to HIGH, which triggers its connected one shots  1041  and  1042  and transitions their outputs from LOW to HIGH for 0.05 seconds and 0.10 seconds, respectively, and then back to LOW, which correspondingly transitions the outputs of the connected INV gates  1051  and  1052 , respectively, from HIGH to LOW to HIGH. While the outputs of the INV gates  1051  and  1052  are LOW, the outputs of their connected AND gates  1001  to  1005  and  1006  to  1010 , respectively, are forced LOW, such that no key presses can cause HIGH outputs for the respectively connected AND gates  1001  to  1005  and  1006  to  1010 , thereby preventing their respectively connected latches  1011  to  1015  and  1016  to  1021  from becoming enabled to pass along their data. Therefore, all latches  1010  to  1021  will remain latched during that 0.05 second interval, and no new notes will be passed to their respective synths  1021  to  1025  for playing, thereby preventing any sounding of pressed keys during that time. 
     If the C5 touch sensor  742  of the left touch sensor outfitted key  701  has been pressed by the end of that 0.05 second interval, the output of the left radio button assembly  720 , and the bus input of 3-state data bus  1031 , will transition from note C4 (n=14) to note C5 (n=21), and the output of the key  701  will transition from LOW to HIGH, which will transition the S input of its connected NOR latch  1070 , the input and output of its connected H-&gt;L delay  1081 , and the connected input of its next connected NOR gate  1080  from LOW to HIGH, and which, since the R input of that NOR latch  1070  is already LOW due to the right touch sensor outfitted key  713  not being pressed and its LOW output being inverted to HIGH by its connected INV gate  1082  so as to thereby force the output of that NOR gate  1080  LOW, will transition the Q output of that NOR latch  1070 , and the D input of its connected D latch  1073 , from HIGH to LOW. 
     Since the right touch sensor outfitted key  713  is not pressed and its output is LOW, when the output of the left touch sensor outfitted key  701  transitions from LOW to HIGH, as discussed above, the output of its connected OR gate  1074  will transition from LOW to HIGH, which will trigger the next connected one shot  1075 , such that its output, and the E input of its connected D latch  1073 , will transition from LOW to HIGH for the 0.10 second duration of one shot  1075 , and then back to LOW, which will, in turn, enable that D latch  1073  for that duration so as to pass its above mentioned LOW D input to its Q output, to the OE input of the right 3-state data bus  1032  and thereby disable that 3-state data bus  1032 , and to its connected INV gate  1061  so as to invert it to HIGH at the OE input of the left 3-state data bus  1031  and thereby enable the output of the left 3-state data bus  1031 . 
     The Q output of that D latch  1073 , and the outputs of those 3-state data buses  1031  and  1032 , will remain latched LOW, enabled, and disabled, respectively, until such time that the outputs of the touch sensor outfitted keys  701  and  713  are both LOW, and then either outfitted key  701  or  713  is pressed so as to once again trigger the aforementioned connected one shot  1075 . 
     With the outputs of the left 3-state data bus  1031  being enabled, as discussed above, note C5 (n=21) will be passed to the input bus of each of its connected D latches  1011  to  1020 , such that, when the output of the above mentioned one shot  1041  returns LOW at the conclusion of its 0.05 second interval, the input and the output of its connected INV gate  1051  will return LOW and HIGH, respectively, so as to then enable the outputs of the next connected AND gates  1001  to  1005  to transition from LOW to HIGH should their respectively connected keys  701 ,  705 ,  708 ,  713 , and  717  be, or become, pressed, thereby enabling their respectively connected D latches  1011  to  1015 . For those D latches  1011  to  1015  that do become enabled, the corresponding note x=n+k (where k is a key-specific integer) will be passed to their respectively connected synths  1021  to  1025 , causing those notes to start sounding. 
     As can be seen from the logic diagram  1000 , if the C5 Major chord keys  701 ,  705 , and  708  are all pressed within that 0.05 second interval and the touch sensor outfitted key  701  was pressed from the C5 touch sensor  742 , regardless of the order in which the keys  701 ,  705 , and  708  were pressed, the C5 Major chord will be sounded. The 0.05 second delay in sounding the C5 Major chord was chosen long enough so as to guarantee that, in most cases, all three chord keys  701 ,  705 , and  708  will all have been pressed within that time period, and short enough so as not to cause noticeable lag in the sounding of the chord. 
     Obviously, if a slightly longer delay were chosen, it would guarantee that more chord presses would be completed within the longer time period; however, it would also cause more noticeable lag in the sounding of the chord. So, rather than increasing that 0.05 second delay, the slightly longer, 0.10 second interval of the other above mentioned one shot  1042  can be utilized, such that, if prior to the completion of that 0.10 second interval, a different touch sensor comes into effect so as to reconfigure the keyboard  700  keys  701  to  717 , the already started incorrect notes will be stopped, and the reconfigured correct notes will be started. While this 0.10 time period will not add any lag to the sounding of a chord, it must not be made too long or else the starting and stopping of the incorrect notes could cause noticeable noise in the playing of the chord. 
     To implement this logic in logic diagram  1000 , at the conclusion of the 0.10 second interval of the aforementioned one shot  1042 , its output, and the input of its connected INV gate  1052 , will return LOW, causing that INV gate  1052  output to return HIGH, thereby enabling the outputs of its connected AND gates  1006  to  1010  to transition from LOW to HIGH should their connected keys  701 ,  705 ,  708 ,  713 , and  717 , respectively, be, or become, pressed, thereby enabling the respectively connected D latches  1016  to  1020 . For those D latches  1016  to  1020  to become enabled, a corresponding note x=n+k (where k is a key-specific integer) will be passed to their respectively connected synths  1021  to  1025 . If those notes are the same as the notes that the synths  1021  to  1025  already started sounding after the 0.05 second one shot  1041  interval, as discussed above, they will be ignored by the synths  1021  to  1025 ; otherwise, for each note that is different, the previously started note will be stopped, and the new note will be started. 
     As can be seen from the logic diagram  1000 , if the C5 Major chord keys  701 ,  705 , and  708  are all pressed, regardless of the pressing order, within the 0.10 second interval, that interval being long enough to guarantee that all the keys of a normally pressed chord will have been pressed, and if the touch sensor outfitted key  701  was pressed from the C5 touch sensor  742 , then the the corresponding notes of the pressed keys will start sounding 0.05 seconds after the start of the key presses, and the C5 Major chord will be correctly playing, usually by that time, but if not, then definitely by the end of the 0.10 second interval. 
     Suppose now, say, 0.30 seconds after the C5 Major chord is released, it were desired to play the first inversion of a C4 Major chord (E4-G4-C5). Since the C5 touch sensor  742  would still be in effect due to the fact that, the Q output of the above mentioned NOR latch  1070  would remain latched LOW when its S input returns LOW and its R input remains LOW, and the C5 touch sensor  742  would, in GUI radio button fashion, remain pressed after its outfitted key  701  has been released if none of its other touch sensors  721  to  741  had since been pressed, none of the keyboard  700  keys  701  to  717  are currently configured for the corresponding notes E4 and G4; therefore, the keyboard  700  would now have to be reconfigured to accommodate this inverted chord. 
     Using the same logic as that discussed above for the logic diagram  1000 , if the E4 touch sensor  739  (not shown in the logic diagram  1000 ) of the left touch sensor outfitted key  701  is pressed, that touch sensor  739  would be put into effect, which would reconfigure the keyboard  700  keys  701  to  717  for the corresponding notes E4 to G#5, respectively, and the subsequent, additional pressing of the G4 key  704  and C5 key  709  would play the first inversion of the C4 Major chord. 
     This, however, is not how the first inversion of a C4 Major chord would be played on an actual piano keyboard. Rather than the chord being based around its E4 note, as discussed above, it would be based around its C5 note. Once the C5 note is located on a piano, the finger position for the first inversion of a Major chord, which is the same for all Major chords, regardless of their root note, can be readily applied. This eliminates having to remember the bass note (i.e., E4) of such an inversion, which would be different for each of the 12 possible Major chord root notes. 
     Implementing such a C5-based first inversion of a C4 Major chord with the logic of logic diagram  1000  requires pressing the right touch sensor outfitted key  713  from its C5 touch sensor  772 , so as to transition the output of the right radio button assembly  750 , and the input of its connected 3-state data bus  1032  with its output still disabled, as discussed above, to note C5 (n=21), and so as to transition the output of that key  713 , the connected input of its OR gate  1074 , and the input of its connected INV gate  1082  from LOW to HIGH, which will transition the output of that INV gate  1082 , and the connected input of its NOR gate  1080 , from HIGH to LOW. 
     Since the output of the left touch sensor outfitted key  701 , the connected input of its OR gate  1074 , and the S input of its connected NOR latch  1070  are currently LOW due to that key  701  being released, and since the other input of the above mentioned NOR gate  1080  is currently LOW due to that key  701  having now been released for 0.30 seconds and its resulting HIGH to LOW output transition having already propagated from the input to the output of the connected H-&gt;L delay  1081  with its 0.20 second HIGH to LOW transition delay, the aforementioned LOW to HIGH output transition of the right touch sensor outfitted key  713  will additionally transition the output of its connected OR gate  1074 , the input of the next connected one shot  1075 , the output of the aforementioned NOR gate  1080 , the R input and Q output of the aforementioned NOR latch  1070 , and the D input of the NOR latch  1070  connected D latch  1073  from LOW to HIGH. 
     The LOW to HIGH transition of the one shot  1075  input will trigger it, and thereby transition its output, and the E input of its connected D latch  1073 , from LOW to HIGH for a duration of 0.10 seconds, which will pass the above mentioned HIGH D input of the D latch  1073  to its Q output, to the OE input of the right 3-state data bus  1032  so as to enable its output, and to the input of the connected INV gate  1061  whose inverted LOW output will be passed to the OE input of the left 3-state data bus  1031  so as to disable its output. 
     With the output of the right 3-state data bus  1032  enabled, note C5 (n=21) will be passed to the input buses of the D latches  1011  to  1020 . At this point, the logic to handle the pressing of the E4, G4, and C5 keys  705 ,  708 , and  713 , respectively, of the first inversion of a C4 Major chord would correspond with the logic for handling the pressing of the C5, E5, and G5 keys  701 ,  705 , and  708 , respectively, of the C5 Major chord, as thoroughly discussed above. 
     A logic diagram for the keyboards  800  and  900  of  FIGS. 14 and 15 , respectively, is shown in  FIG. 17 , and is designated generally as  1100 . The logic of this current logic diagram  1100  is nearly identical to that of the previous logic diagram  1000  in  FIG. 16 , but with additional logic to handle the left and right touch sensor outfitted black keys  702  and  714 , respectively, and the left and right black key radio button assemblies  820  and  850 , respectively, that now supplement the left and right touch sensor outfitted white keys  701  and  713 , respectively, and the left and right white key radio button assemblies  720  and  750 , respectively. To similarly reduce the complexity of the current logic diagram  1100 , for each of these two added touch sensor outfitted black keys  702  and  714 , only three touch sensors  821 ,  835 , and  842 , and  851 ,  865 , and  872 , respectively, of their total touch sensors  821  to  842  and  851  to  872 , respectively, are shown. 
     As is shown in the current logic diagram  1100 , rather than the left touch sensor outfitted white key  701  being directly connected, as it was in the previous logic diagram  1000 , to the S input of the NOR latch  1070  and to the input of the H-&gt;L delay  1081 , it is now OR&#39;d with the left touch sensor outfitted black key  702  via an OR gate  1181 . Similarly, rather than the right touch sensor outfitted white key  713  being directly connected, as it was in the previous logic diagram  1000 , to the INV gate  1082 , it is now OR&#39;d with the right touch sensor outfitted black key  714  via an OR gate  1182 . As such, with regard to the NOR latch  1070 , H-&gt;L delay  1081 , and INV gate  1082 , their logic that was previously controlled by the left touch sensor outfitted white key  701  and by the right touch sensor outfitted white key  713  is now controlled by either the white or black left touch sensor outfitted key  701  or  702 , respectively, and by either the white or black right touch sensor outfitted key  713  or  714 , respectively. 
     As is further shown in the current logic diagram  1100 , rather than the left and right white key radio button assemblies  720  and  750 , respectively, being each directly connected, as they were in the previous logic diagram  1000 , to the respective left and right 3-state data buses  1031  and  1032 , they are now multiplexed with the left and right black key radio button assemblies  820  and  850 , respectively, via the left 2:1 MUX  1131  and the right 2:1 MUX  1132 , respectively. The left 2:1 MUX  1131  is controlled by the left touch sensor outfitted keys  701  and  702  via a connected NOR latch  1141 , NOR gate  1151 , H -&gt;L delay  1161 , INV gate  1171 , and D latch  1191 , in the same manner that the right 3-state data bus  1032  was controlled in the previous logic diagram  1000  by the touch sensor outfitted white keys  701  and  713  via the respectively connected NOR latch  1070 , NOR gate  1080 , H-&gt;L delay  1081 , INV gate  1082 , and D latch  1073 . Similarly, the right 2:1 MUX  1132  is correspondingly controlled by the right touch sensor outfitted keys  713  and  714  via a connected NOR latch  1142 , NOR gate  1152 , H-&gt;L delay  1162 , INV gate  1172 , and D latch  1192 , respectively. 
     With this additional logic, it is now possible to play a chord of any type and root note, simply by positioning the fingers for that chord type, positioning the hand for the touch sensor associated with that root note, and then pressing. 
     The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. Accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.