Patent Publication Number: US-7897863-B2

Title: Electronic keyboard instrument having key driver

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on Japanese Patent Application 2007-077197, filed on Mar. 23, 2007, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     A) Field of the Invention 
     This invention relates to an electronic keyboard instrument with a key driver, and more in detail, an electronic keyboard instrument with a musical keyboard including plurality of keys and a key driver to drive each key interlocked with reproduction of automatic performance data. 
     B) Description of the Related Art 
     Conventionally, an electronic keyboard instrument that equips a musical tone generator and a keyboard including plurality of keys, executes automatic performance by driving the musical tone generator based on the automatic performance data and drives each key interlocked with the reproduced automatic performance is well-known (for example, refer to Japanese Laid-Open Patent H08-335079). 
     It takes some time from providing the performance (key-driving) event to a key-driving circuit until a key is driven (to be in a condition of being pressed). When the performance event is provided to both of the key-driving circuit and the musical tone generator at the same time, generation of key movement and sound disagree, and it brings discomfort. Therefore, in the above-described electronic musical instrument, disagreement of generation of the key movement and the sound is prevented by providing the performance event to the musical tone generator after a predetermined time after providing the performance event to the key-driving circuit. 
     In the conventional electronic keyboard instrument with a key driver, a timing adjustment process is executed while reproducing the automatic performance data, and it is difficult to execute a so-called quick start. The “quick start” is a reproducing method in an automatic performance for reproducing a predetermined period of performance data at high speed when there is a predetermined space or an event relating to an initial setting other than a performance event (note-on and off-event) relating to sound at a beginning of the performance data and starting reproduction at a normal speed from the first performance event. For example, when there is performance data having a plurality of tracks and when a part of the tracks is used for key driving, the performance event is reproduced at high speed until the first appearing performance event of the plurality of the tracks. Then, when reproduction is executed at normal speed from that performance event, and when the performance event is used for also key driving, the performance event is provided to the key-driving circuit and to the musical tone generator after the predetermined time after providing to the key-driving circuit. However, when the performance event is not used for key driving, and when the performance event is provided to the musical tone generator after the predetermined time, reproduction start will delay for the predetermined time, and it cannot be called “quick start”. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an electronic keyboard instrument with a key driver that can simplify a reproduction process when keys are driven along with reproduction of automatic performance data. 
     According to one aspect of the present invention, there is provided an electronic keyboard instrument, comprising: a storage device that stores automatic performance data including a first event for generating a musical tone and first timing data that defines a reproduction timing of the first event; a key-driving data generator that generates key-driving data including a second event corresponding to the first event included in the automatic performance data and second timing data that defines a reproduction timing of the second event and precedes the first timing data for a predetermined time; a keyboard that has a plurality of keys; a key driver that drives each of the plurality of keys in accordance with the key-driving data; a reproduction device that reproduces the automatic performance data and the key-driving data in parallel, and wherein the key-driving data generator generates the key-driving data before the reproduction device starts the reproduction. 
     According to the present invention, a reproduction process can be simplified when keys are driven along with reproduction of automatic performance data. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram showing a basic structure of an electronic keyboard instrument  1  according to an embodiment of the present invention. 
         FIG. 2A  and  FIG. 2B  are schematic diagrams showing a structure of a keyboard  22  according to the embodiment of the present invention. 
         FIG. 3  is a schematic diagram showing a structure of performance data PD and driving data MD formed based on the performance data PD according to the embodiment of the present invention. 
         FIG. 4  is a flow chart showing an automatic performance process according to the embodiment of the present invention. 
         FIG. 5  is a flow chart showing a driving data forming process that is executed at Step SA 4  in  FIG. 4 . 
         FIG. 6  is a flow chart showing a calculation process of a timing difference dT that is executed at Step SB 17  in  FIG. 5 . 
         FIG. 7  is a schematic view for explaining the calculation process of the timing difference dT shown in  FIG. 6 . 
         FIG. 8  is a flow chart showing a reproduction starting process that is executed at Step SA 6  in  FIG. 4 . 
         FIG. 9A  and  FIG. 9B  are schematic diagrams for explaining the reproduction starting process shown in  FIG. 8 . 
         FIG. 10  is a flow chart showing the process executed at Step SA 10  in  FIG. 4  for processing the key-driving event just before paused. 
         FIG. 11A  and  FIG. 11B  are schematic diagrams for explaining the key-driving event process just before pausing shown in  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a block diagram showing a basic structure of an electronic keyboard instrument  1  according to an embodiment of the present invention. 
     A RAM  7 , a ROM  8 , a CPU  9 , a detector  11 , a displaying circuit  13 , an external storage device  15 , a musical tone generator  18 , an effecter  19 , a communication interface (I/F)  21  and a key-driving circuit  23  are connected to a bus  6 . 
     The RAM  7  has a working area of the CPU  9  that stores buffer region such as a reproduction buffer and the like, a flag, a register and various parameters. 
     Various parameters and controlling programs or programs for realizing the embodiment of the present invention can be stored in the ROM  8 . In this case, it is not necessary to store the programs and the like in the external storage device  15  in duplicate. 
     The CPU  9  executes calculations and controls the electronic keyboard instrument  1  in accordance with control programs or programs for realizing the embodiment of the present invention stored in the ROM  8  or the external storage device  15 . The timer  10  is connected with the CPU  9  and provides a standard clock signal and interrupt timing to the CPU  9 . 
     A user can input, set and select various settings by using a setting operator  12  connected to the detector  11 . The setting operator  12  may be any types of operators that can output signals corresponding to the user&#39;s input operations such as an alpha-numeric keyboard, a mouse, a switch, a pad, a fader, a slider, a rotary encoder, a joy-stick, a jog-shuttle and the like. Moreover, the setting operator  12  may be a software switch to be displayed on a display  14  and operated by using other operator such as a mouse and the like. 
     The displaying circuit  13  is connected to the display  14  and can display various kinds of information on the display  14 . The user executes various kinds of input and setting operations with reference to the information displayed on this display  14 . Moreover, the display  14  may be configured by connecting to an external displaying device. 
     The external storage device  15  is configured of at least one combination of a hard disk, the FD (flexible disk or Floppy Disk (trademark)), the CD (compact disk), the DVD (digital versatile disk) and storing medium such as semiconductor memory such as a flash memory and those driving devices. The storing medium may be a removed type or built-in in the electronic keyboard instrument  1 . 
     A plurality of automatic performance data PD ( FIG. 4 ) and driving data MD ( FIG. 4 ) used in the embodiment of the present invention and the like can be stored in the external storage device  15 , and the program for realizing each embodiment of the present invention and other program for controlling the electronic keyboard instrument  1  can be also stored. Moreover, when the program for realizing each embodiment of the present invention and other program for controlling the electronic keyboard instrument  1  are stored in the external storage device  15 , it is not necessary to store them duplicately in the ROM  8 . Moreover, only some of the programs may be stored in the external storage device  15  and other programs may be stored in the ROM  8 . 
     The musical tone generator  18  generates musical tone signals corresponding to the performance data PD stored in the external storage device  15 , the ROM  8  or the RAM 7 , or the performance signals provided from a keyboard  22  or the external device connected with the communication interface  21  and provides the generated signals to the sound system  20  via the effecter  19 . 
     The effecter  19  adds various kinds of musical effects to the musical tone signals provided from the musical tone generator  18 . A sound system  20  includes a D/A converter and a loudspeaker and converts the digital musical tone signals to analogue signals for sounding. 
     The keyboard  22  is an operator including a plurality of keys  220  for inputting a musical performance by a user, a key-driving system  225  ( FIG. 2 ) corresponding to each key, and an operation start timing and a finish timing to the keys by the user are input as a key-on signal and a key-off signals at a pitch corresponding to the key operated by the user. Moreover, each key  220  of the keyboard  22  is driven by the key-driving system  225  equipped for each key in accordance with the automatic performance data PD ( FIG. 4 ) to be reproduced in the electronic keyboard instrument  1  (for example, in accordance with the driving data MD ( FIG. 4 )). Moreover, structure of the keyboard  22  will be explained with reference to  FIG. 2A  and  FIG. 2B . 
     The key-driving circuit  23  controls the key-driving system  225  equipped with each key  220  corresponding to a pitch designated by the key-driving event MV at a timing designated by timing data TD included in the later-described driving data MD ( FIG. 4 ). 
     The communication interface  21  is at least one of the communication interface such as a wired I/F dedicated for music such as MIDI interface, an universal short-distanced wired I/F such as a USB interface, the IEEE1394 interface and the like, an universal network I/F such as the Ethernet (trademark) and the like and an universal short-distanced wireless I/F such as a wireless LAN, the Bluetooth (trademark) and the like. 
     The communication I/F  21  can be connected to a communication network  3  such as a LAN (local area network) and the Internet and can be connected to a server  2  and other electronic musical instrument with each other via the communication network  3 . 
       FIG. 2A  and  FIG. 2B  are schematic diagrams showing a structure of a keyboard  22  according to the embodiment of the present invention. The diagram shows one white key  220  of a plurality of the keys  220  and a structure of a peripheral system corresponding to the white key  220 , and all of the keys  220  have almost same structure except difference in shapes of the white key and the black key.  FIG. 2A  shows a condition of a non-operated (released) key  220  and the peripheral system.  FIG. 2B  shows a condition of an operated (pressed) keys  220  and the peripheral system. Moreover, arrows A to C and a white arrow in the diagram represent moving directions of the components. 
     Each key  220  includes, as a peripheral system, a key fulcrum  221 , a hammer  222 , a contacting part  223  between key and the hammer  222 , a hammer fulcrum  224  and a key-driving system  225 . Moreover, each key  220  includes a switch (not shown in the drawings) for detecting ON/OFF (pressing/releasing) of each key and key-pressing velocity. 
     When a user operates (presses) the key  220 , a key free-end (tip)  220   m  of the key  220  turns in a direction C around the key fulcrum  221 . Then, a hammer contacting end  222   f  of the hammer  222  that is contacted with the key  220  by the contacting part  223  around the key free-end  220   m  turns in a direction B around the hammer fulcrum  224 , and the hammer free-end  222   m  turns in a direction A. At this time, the key becomes a condition shown in  FIG. 2B , and a key-on signal is generated by contacting the hammer contacting end  222   f  with the switch (not shown in the diagram) for detecting key pressing velocity, etc. Thereafter, by releasing a user&#39;s finger from the key  220 , the key free-end  220   m , the hammer contacting end  222   f  and the hammer free-end  222   m  naturally turn in reversed directions as before by a weight of the hammer  222  to return to an original condition shown in  FIG. 2A . 
     The key-driving system  225  is configured of, for example, a push-typed solenoid or a push-pull-typed solenoid. It is driven by a control signal from the key-driving circuit  23  in  FIG. 1 . Moreover, in this specification, driving a key in the white arrow direction in the drawing (to make it in a condition shown in  FIG. 2B ) is called “the forward direction drive”, and driving a key in a step-back direction to make it in the original condition (a condition shown in  FIG. 2A ) is called “the reverse direction drive”. The terms “drive” or “driving” indicates either one or both of the forward direction drive and the reverse direction drive. That is, when a drive event (key-on event) MV of the driving data MD is reproduced, a driving control signal is input (a coil of the solenoid is electrically conducted) by the key-driving circuit  23 , and the driving part  225   m  is driven in the forward direction indicated by the white arrow in the drawing based on the control signal. By this driving part  225   m  pushing up the hammer free-end  222   m , the hammer free-end  222   m  turns in the direction A, and the hammer contacting end  222   f  of the hammer  222  that is contacted with the key  220  by the contacting part  223  near the key free-end  220   m  turns in the direction B around the hammer fulcrum  224 . Then, the key free-end (tip)  220   m  of the key  220  turns in the direction C around the key fulcrum  221  because the hammer contacting end  222   f  is contacted with the key  220  by the contacting part  223  near the key free-end  220   m . As described in the above, by driving the key-driving system  225  in the forward direction, the key  220  can be turned as same as the above-described key-pressing-operation by a user, and the key  220  can be driven as if a user presses the key without a key-pressing-operation by a user. 
     Moreover, when a driving event (key-off event) MV of the driving data MD, all-note-off or all-sound-off is reproduced, a drive releasing control signal is input (conducted condition to the coil of the solenoid is changed or the electric current is switched to a return electric current) by the key-driving circuit  23 , and the driving part  225   m  is driven to the reversed direction that is a reversed direction of the white arrow based on the control signal. 
     Moreover, in the above-described example, the key  220  has the hammer  222 ; however, the key  220  may not be equipped with the hammer  222 . In that case, the key-driving system  225  is configured by a pull-typed solenoid and the like, and the key  220  may be directly driven without the hammer  222 . Moreover, even if the key has the hammer  222 , the key may be directly driven. Moreover, in the above-described example, the solenoid is used as the key-driving system  225 ; however, the key-driving system  225  may be any types of driving systems if it can quickly push up or pull down the hammer  222  in accordance with the control signal from the key-driving circuit  23 . 
     Moreover, the key-driving system  225  is not limited to ON/OFF by conducting and interrupting electric current, but the turning angle and speed of the key  220  may be controlled based on a parameter such as a velocity and the like. 
       FIG. 3  is a schematic diagram showing a structure of performance data PD and driving data MD formed based on performance data PD according to the embodiment of the present invention. 
     The performance data PD is automatic performance data such as MIDI data, etc. A tempo track TTD (for example, a tempo track  0 ) and a plurality of performance tracks PTD (for example, performance tracks  1  to  16 ) are included in the performance data PD. Moreover, the performance data PD is stored, for example, in the external storage device  15  or the ROM 8  in  FIG. 1 . Furthermore, the performance data PD is not only stored in the electronic keyboard instrument  1  but obtained via the communication network  3 . For example, the data may be downloaded by a quasi-streaming (a downloading method for downloading MIDI data and deleting automatically after reproducing it) from distribution service of the performance data in the communication network  3  such as the Internet. Moreover, the performance data PD is stored in the external storage device  15  in  FIG. 1  and in a reproduction buffer such as the RAM  7  when reproduced. The performance data PD that is temporally downloaded by quasi-streaming and the like is stored in the reproduction buffer such as the RAM  7  and the like and deleted after finishing reproduction. 
     The performance track PTD includes the timing data TD and various events EV to be reproduced at timings indicated by the timing data. 
     The timing data TD is data represented by tick (or clock) that is a quotient of a predetermined note length divided by a predetermined number (resolution). As an example, when a quarter note (crotchet) is divided by 1920, it is “resolution=1920” and a length of 1920 ticks is equivalent to a length of a quarter note. Moreover, since the tick is a quarter note divided by a resolution, a time length of the tick changes depending on a tempo. The timing data TD may be represented by an absolute timing (number of the ticks) from a predetermined position such as a beginning of the track (performance data PD) or by a relative timing (number of the Ticks) from previous event (timing data TD). In the embodiment of the present invention, the timing data TD is represented by the absolute timing from the beginning of the performance data PD. 
     The event EV is data to be reproduced (output to the musical tone generator  18  or the effecter  19  in  FIG. 1 ) at a timing indicated by the timing data TD, and for example, the performance track PTD includes the events EV such as a note event, a program change, a control change (all-note-off, all-sound-off and the like), and system exclusive events. The note event may consist of distinct note-on and note-off events or be a combination of a note-on event and a gate time. In the embodiment of the present invention, each note event is recorded as a combination of the note-on event and the gate time. 
     The tempo track TTD consists of the timing data TD and a tempo change event TP to be reproduced at the timing indicated by the timing data TD. The tempo change event TP is for setting reproduction tempo of the performance data PD. 
     The driving data MD is data for key-driving to be formed based on the performance data PD at the later-described driving data forming process in  FIG. 5 . The driving data MD has same numbers of key-driving tracks MTD (for example, the key-driving tracks  1  to  16 ) as the performance data PD on which the driving data MD is based. Moreover, the key-driving tracks  1  to  16  respectively correspond to the performance tracks  1  to  16 . Each key-driving track MTD includes the timing data TD, the key-driving event MV to be reproduced at timing indicated by the timing data TD and the timing difference dT. The key-driving event MV is a note event corresponding to that stored in an original performance data PD and data to be reproduced (output to a key-driving circuit  23  in  FIG. 1 ). Moreover, a part of the control change events (all-note-off and all-sound-off) may be stored as the key-driving event MV depending on necessity. Moreover, the note event (key-driving event MV) in the key-driving track MTD may include parameters such as velocity and the like for controlling velocity of key-driving and a rotation distance (angle) of the key  220  in addition to a pitch (note number) and a gate time. 
     The key-driving event MV in the key-driving track MTD is formed based on the event of the corresponding performance track PTD. All contents of these events are the same but reproduction timings of both events (the event EV and the key-driving event MV) are different. The key driving takes a predetermined time (for example, approximately 50 msec) from the key-driving system  225  ( FIG. 2 ) starts to drive (for example, from an electric current is supplied to a solenoid) until the key  220  is driven to be in a condition of being pressed. The event MV in the key-driving track MTD is reproduced at timing prior to the corresponding event EV in the performance track PTD for the above-described predetermined time. 
     The timing difference dT corresponds to a duration corresponding to the above-described predetermined time and is represented by “tick”. Number of ticks corresponding to the predetermined time (for example, 50 msec) changes depending on the performance tempo. Therefore, a value of the timing difference dT depends on the tempo. 
     For example, when an event EV 1  to be reproduced at a timing B in a performance track  1  is a note event, an event MV 1  in a corresponding key-driving track  1  is the same note event, and its timing is a value obtained by deducting the timing difference dT from the timing B in the performance track  1  (timing B-dT). 
     Moreover, in the embodiment of the present invention, the key-driving tracks MTD are formed based on all performance tracks PTD included in the original performance data PD. Actually a track to be used for key driving is one or a part of the performance tracks PTD. Therefore, the performance track or tracks PTD to be used for forming the key-driving track or tracks may be arbitrarily selected by a user or automatically selected in accordance with a predetermined rule. Typically, tracks corresponding to a right-hand part and a left-hand part of a keyboard performance such as a piano are selected. However, other part can be a driving target by arbitral selection of a user. 
       FIG. 4  is a flow chart showing an automatic performance process according to the embodiment of the present invention. This process is, for example, booted up when an automatic performance mode of the performance data PD is selected on the electronic keyboard instrument  1  and executed by the CPU  9  in  FIG. 1 . 
     At Step SA 1 , the automatic performance process starts. At Step SA 2 , setting of a reproduction mode is executed. The setting of a reproduction mode include, for example, setting a selection of (a start mode) from normal start and quick start and setting ON/OFF (key-driving mode) of the key-driving, and this setting or settings is/are stored as a flag or flags in the RAM  7  in  FIG. 1 . 
     At Step SA 3 , the performance data PD to be reproduced in this automatic performance process is selected (song selection), and a driving target (the performance track PTD corresponding to the driving track MTD transmitted to the key-driving circuit  23 ) is selected. The performance data PD is not only selected from the performance data PD stored in the electronic keyboard instrument  1  but may be selected from the performance data PD distributed by a distribution service on the Internet and the like. Moreover, as for selection of the driving track, a user may select one or a plurality of tracks by operating the operator  12  ( FIG. 1 ), or the selection of the driving track may be automatically executed in accordance with a predetermined rule that has been determined in advance. For example, the first track (track  1 ) and the second track (track  2 ) are respectively defined as a right-hand part and a left-hand part and are automatically selected as the driving targets. 
     At Step SA 4 , the later-described driving data forming process in  FIG. 5  is executed. At this step, the driving data MD is formed based on the performance data selected at Step SA 3 . 
     At Step SA 5 , it is detected whether or not starting reproduction is instructed by a user&#39;s operation of the operator  12 . When the instruction of starting reproduction is detected, the process proceeds to Step SA 6  as indicated with an arrow “YES”. When the instruction of starting reproduction is not detected, the process at Step SA 5  is repeated as indicated with an arrow “NO” to wait for the instruction of starting reproduction. 
     At Step SA 6 , a reproduction start process described later in  FIG. 8  is executed. In the reproduction start process, reproduction of the performance data PD selected at SA 3  starts in accordance with the setting of the normal start or the quick start on the reproduction modes set at Step SA 2 . Then, the process proceeds to Step SA 7 . 
     At Step SA 7 , it is judged whether or not pause of reproduction is instructed by the user by operating the operator  12 . When pause is instructed, the process proceeds to Step SA 8  as indicated with an arrow “YES”. When pause is not instructed, the process proceeds to Step SA 12  as indicated with an arrow “NO”. 
     At Step SA 8 , reproduction of the performance data PD and the driving data MD pauses, and all-note-off is provided to the key-driving circuit  23  and the musical tone generator  18 . By that, musical tone generation based on the performance data PD by the musical tone generator  18  is terminated, and the key-driving system  225  returns to the original condition (releasing key state) as shown in  FIG. 2A . 
     At Step SA 9 , it is judged whether or not the user instructs restarting reproduction by using the operator  12 . When the user instructs restarting reproduction, the process proceeds to Step SA 10 . When the user does not instruct restarting reproduction, the process of Step SA 9  is repeated to wait until the user instructs restarting reproduction. 
     At Step SA 10 , a process for processing the key-driving event just before paused position is executed. Details of this process will be describe with reference to  FIG. 10 . This process is for certainly reproducing the key-driving event MV when the key-driving event MV is positioned before the paused position and the performance event EV corresponding to the key-driving event MV is positioned after the position paused at Step SA 8 . Thereafter, the process proceeds to Step SA 11  to restart reproduction. The restarting reproduction here is to release the paused condition at Step SA 8 . Then, the process proceeds to Step SA 14 . 
     At Step SA 12 , reproduction process is executed. In this reproduction process, the key-driving track MTD and the performance track PTD are reproduced in parallel. Moreover, when plurality of the key-driving tracks MTD and plurality of the performance tracks PTD are selected, all the tracks are reproduced in parallel. Moreover, reproduction at this step is to drive the key-driving system  225  and to drive the keys  220  by reading out the note event MV (and other event depending on necessity) from the key-driving track MTD that is the driving target to be provided to the key-driving circuit  23 . Moreover, the note event and other event are provided from the performance PTD to the musical tone generator  18  and the effecter  19  to sound musical tones corresponding to the performance data PD from the sound system  20  and the like. 
     Moreover, in the reproduction process at Step SA 12 , it is not necessary to execute the timing adjustment between the key-driving note event and the performance note event as in the conventional technique, and the events are reproduced by simply reproducing both data in parallel at their reproducing timings, and so the reproduction process can be executed very simply. 
     At Step SA 13 , other process (or processes) is/are executed. At this step, instructions such as setting change and the like relating to the automatic performance by operating the operator  12  by the user are detected, and processes based on the instructions such as the detected setting change and the like are executed. More in detail, the instructions may be change of the driving target track, switching ON/OFF of the key-driving and the like. When the driving target track is changed, the driving target track to be reproduced at Step SA 12  that may be executed after executing the process at Step SA 13  will be changed. When the key-driving is turned off, reproduction of the driving track will stop at Step SA 12  to be executed after this step. When the key-driving is turned on, reproduction of the driving track will start at Step SA 12  to be executed after this step. Moreover, tempo setting can be changed. When the tempo setting is changed, the driving data forming process at Step SA 4  is executed once again. Moreover, when the tempo is changed, the timing difference dT in the driving data MD may be changed by being multiplied with the change ratio of the tempo instead of executing the driving data forming process at Step SA 4  once again, and the timing of each driving event MV in the driving data MD may be changed. Then, the process proceeds to Step SA 14 . 
     At Step SA 14 , it is judged whether or not the user instructs termination of reproduction by operating the operator  12  and whether or not the reproduction has been finished by reproducing the performance data PD to the end. When the reproduction finishes, that is, when the instruction of terminating the reproduction is detected or when all the performance data PD has been reproduced to the end, the process proceeds to Step SA 15  as indicated with an arrow “YES” to finish the automatic performance process. When the reproduction does not finish, the process returns to Step SA 7  as indicated with an arrow “NO” to repeat the process after that process. 
       FIG. 5  is a flow chart showing a driving data forming process that is executed at Step SA 4  in  FIG. 4 . In this process, the driving data MD is formed in advance based on the performance data PD before starting reproduction of the performance data PD selected at Step SA 3  in  FIG. 4 . 
     At Step SB 1 , a driving data forming process starts. At Step SB 2 , pointers of the tempo track TTD included in the performance data PD selected at Step SA 3  in  FIG. 4  and all the performance tracks PTD (hereinafter, the whole tracks are collectively called the process target track in this driving data forming process) are set to the beginning of the tracks. 
     At Step SB 3 , the beginning data (the beginning timing data TD) of the process target track is read out, and timing data read out from track n is set to a corresponding track timing register n (n=0 to 16). 
     At Step SB 4 , the pointer of each process target track is increased by one. At Step SB 5 , “0” is set for the present timing register cT to initialize. At Step SB 6 , “0” is set for the track number register n. 
     At Step SB 7 , a timing value (tick) that is presently set in the timing register cT is compared with a timing value (tick) that is set in the track timing register n. When the timing value (tick) in the present timing register cT and the timing value (Tick) in the track timing register n are same, the process proceeds to Step SB 13  as indicated with an arrow “YES”. When the timing values are different, the process proceeds to Step SB 8  as indicated with an arrow “NO”. 
     At Step SB 8 , it is judged whether or not the value set in the track number register n is less than “16”. Moreover, in the embodiment of the present invention, it is supposed to have one tempo track “0” and 16 performance tracks  1 - 16 . When the current value of the track number register n is over “16”, it is considered that the process for all the tracks at the present timing cT finished; therefore, it is judged whether or not the value in the track number register n is less than “16”. Moreover, this value is made to be same as number of all the performance tracks included in the performance data PD. For example, when number of the tracks (including the tempo track) in the performance data PD is “9”, the value is set to “8”. When the current value of the track number register n is less than “16”, the process proceeds to Step SB 9  as indicated with an arrow “YES”. When the current value of the track number register n is not less than “16”, the process proceeds to Step SB 10  as indicated with an arrow “NO”. 
     At Step SB 9 , “1” is added on the value in the track number register n (n=n+1), and the process proceeds to Step SB 7 . By that, the process target in the process after the Step SB 7  to be executed after this step will be a track having the next track number. 
     At Step SB 10 , it is judged whether or not the pointer reaches to the end of the process target track. When the pointer reached to the end, the process proceeds to Step SB 11  as indicated with an arrow “YES” and thereafter the process proceeds to Step SA 5  in  FIG. 4 . When the pointer does not reach to the end, the process proceeds to Step SB 12  as indicated with an arrow “NO”. Then, “1” is added to the value of the present timing register cT (the present timing cT is added with 1 tick) and then the process proceeds to Step SB 6 . 
     At Step SB 13 , the data at the pointer position of the track of which track number is n (track n) is read out. At Step SB 14 , it is judged whether or not the read data is the timing data TD. When it is the timing data TD, the process proceeds to Step SB 15  as indicated with an arrow “YES”. When it is other data (event data), the process proceeds to Step SB 16  as indicated with an arrow “NO”. 
     At Step SB 15 , the value (tick) of the timing data TD read out at Step SB 13  is set in the track timing register n. Then, the process proceeds to Step SB 24 . 
     At Step SB 16 , it is judged whether or not the data read out at Step SB 13  is a note event EV or other event EV (all-note-off, all-sound-off and the like) that is necessary for the key-driving track. When it is the note event EV or the other event EV that is necessary for the key-driving track, the process proceeds to Step SB 17  as indicated with an arrow “YES”. When it is not the note event EV or the other event EV that is necessary for the key-driving track, the process proceeds to Step SB 20  as indicated with an arrow “NO”. 
     At Step SB 17 , a calculation process of the timing difference dT described later in  FIG. 6  is executed. As described in the above, the timing difference dT is timing difference for reproducing the key-driving event MV prior to reproduction of the corresponding performance event (note event) EV for approximately a predetermined time (50 msec). Since it varies depending on the current set tempo and the tempo change timing, the timing difference dT is calculated at this process. Then, the process proceeds to Step SB 18 . 
     At Step SB 18 , the driving timing mT that is the reproduction timing of the key-driving event MV corresponding to the note event red out at Step SB 17  is calculated by subtracting the value of the timing difference dT calculated at Step SB 17  from the value of the present timing register cT. 
     At Step SB 19 , it is defined that the driving timing mT calculated at Step SB 18  is the timing data TD and the event data EV read out at Step SB 13  is the driving event MV, and they are written into the driving track n with the timing difference dT calculated at Step SB 17 . Then, the process proceeds to Step SB 24 . Moreover, the event data EV read out at Step SB 13  may be used as the driving event MV with keeping the same contents, or it may be used as the driving event MV by using only the necessary parameter such as pitch (note number), gate time and the like. 
     At Step SB 20 , it is judged whether or not the event data read out at Step SB 13  is a tempo event TP. When it is a tempo event TP, the process proceeds to Step SB 21  as indicated with an arrow “YES”. When it is other event (for example, system exclusive, program change and the like), the process proceeds to Step SB 24  as indicated with an arrow “NO” because it does not relate to the driving data. 
     At Step SB 21 , the current set tempo (that is, a current value in the tempo register) is set in the previous tempo register. Moreover, it is defined that the tempo set by a user before starting this key driving data forming process or an initial set value in the electronic keyboard instrument  1  with a key driver has been set to the present tempo register. 
     At Step SB 22 , the value of the present timing register cT is set to the previous tempo change timing register. At Step SB 23 , the value of the tempo event TP that is read out at Step at SB 13  is set to the present tempo register. Then, the process proceeds to Step SB 24 . 
     At Step SB 24 , the pointer of the track n is increased by one. Then, the process returns to Step SB 7  to repeat the processes after that. 
     As described in the above, in the embodiment of the present invention, before the reproduction process of the performance data PD to be executed after Step SA 6 , the key-driving data MD having timing data adjusted in advance is formed from the performance data PD at Step SA 4  in  FIG. 4 . Therefore, in the reproduction process after Step SA 6 , it is not necessary to adjust timing between the performance event and the key-driving event. Therefore, it can be prevented that the reproduction process becomes complicated, and an electronic keyboard instrument with a key driver can be developed and manufactured without obtaining the reproduction process that is adopted in the conventional electronic musical instrument. 
       FIG. 6  is a flow chart showing a calculation process of a timing difference dT that is executed at Step SB 17  in  FIG. 5 . 
       FIG. 7  is a schematic view for explaining the calculation process of the timing difference dT shown in  FIG. 6 . 
     The timing difference dT is a value obtained by converting a predetermined time (50 msec in this embodiment) from starting of the key-driving system  225  ( FIG. 2 ) until the key  220  actually becomes a state of being pressed to a timing value (number of ticks). Number of ticks for the predetermined time (50 msec) varies in accordance with the performance tempo. 
     At Step SB 171 , a timing difference dT calculation process starts, and a value calculated by an equation “60 multiplied by 1000 divided by current set resolution (60·100/current set resolution)” is set in a register tmp. Moreover, since the resolution in the embodiment of the present invention is “1920”, this value will be “60·100/1920=31.25”. 
     At Step SB 173 , the timing difference dt is calculated by an equation “the predetermined time (50 msec in the embodiment of the present invention) multiplied by the value in the present tempo register divided by the value in the register tpm (50·current tempo/tpm)”. By that, number of ticks for the predetermined time in a single tempo can be calculated. For example, when the resolution is “1920”, the predetermined time is “50 msec” and the present tempo is “120”, the value (number of ticks corresponding to the predetermined time) will be “50·120/31.25”; therefore, the timing difference dt will be “192ticks”. 
     At Step SB 174 , it is judged whether or not the value of the previous tempo change register set at Step SB 22  in  FIG. 5  is over the value obtained by subtracting the timing difference dT calculated at Step SB 173  from the present timing register cT (cT−dT). 
     At Step SB 174 , when the value of the previous tempo change register is less than the value “cT−dT”, the key-driving event MV 1  corresponding to the performance event EV 1  shown in  FIG. 7  is positioned after the previous tempo change event TP 1 ; therefore, it is obvious that there is no tempo change between the performance event EV 1  and the key-driving event MV 1 . Therefore, in this case, the process proceeds to Step SB 177  as indicated with an arrow “NO” and the timing difference calculated at Step SB 173  is used without any change. Then, the process returns to Step SB 18  in  FIG. 5 . 
     At Step SB 174 , when the value of the previous tempo change register is not less than the value “cT−dT”, the previous tempo change event TP 2  is between the performance event EV 2  shown in  FIG. 7  and the corresponding key-driving event MV 2 ; therefore, it is necessary that the timing (number of ticks) corresponding to the predetermined time (50 msec) between the event MV 2  and the event EV 2  is recalculated. Therefore, in this case, the process proceeds to Step SB 175  as indicated with an arrow “YES”, and the timing difference dT is recalculated based on the two tempo values before and after being changed. 
     At Step SB 175 , a value obtained by subtracting the value in the previous tempo change register set at Step SB 22  in  FIG. 5  from the value in the present register cT is set to the register Xmsec. By that, the timing (number of ticks) of Xmsec shown in  FIG. 7  is calculated. 
     At Step SB 176 , the timing difference dT is calculated by an equation “Xmsec+(50-Xmsec·tpm/present tempo register value)·previous tempo register value/tpm”. More in detail, for example, when the resolution is “1920”, the predetermined time is “50 msec” and the previous tempo (TP 1 ) is “120”, the previous tempo (TP 2 ) is “100” and the timing difference Xmsec between the event TP 2  and the EV 2  in  FIG. 7  is “100 ticks”, the timing difference dT will be “172 ticks” (100+(50−100×31.25/100)×120/31.25). Then, the process proceeds to Step SB 177  to return to Step SB 18  in  FIG. 5 . 
     By calculating the timing difference dT as described in the above, the timing difference dT updated with the set tempo can be set. Moreover, the timing difference dT of number of ticks corresponding to the predetermined time can be set between the driving event MV and the performance event EV even if the tempo has been changed during the predetermined time (50 msec) between the driving event MV and the performance event EV. 
       FIG. 8  is a flow chart showing a reproduction starting process that is executed at Step SA 6  in  FIG. 4 . In the reproduction start process, reproduction of the selected performance data PD selected at Step SA 3  starts in accordance with the normal start setting or the quick start setting on the reproduction modes, one of which has been set at Step SA 2  in  FIG. 4 . 
     At Step SC 1 , the reproduction start process starts, and it is judged whether or not the reproduction mode (start mode) is quick start mode. This is judged with reference to the flag of the reproduction mode (start mode) set at Step SA 2  in  FIG. 4 . When the reproduction mode (start mode) is on the quick start mode, the process proceeds to Step SC 3  as indicated with an arrow “YES”. When the reproduction mode is on the normal start, the process proceeds to Step SC 7  as indicated with an arrow “NO”, and reproduction starts at normal speed. 
     At Step SC 3 , it is judged whether or not the key-driving is turned on. This is judged with reference to the flag of the reproduction mode (key-driving mode) set at Step SA 2  in  FIG. 4 . When the reproduction mode is on the key-driving mode (the key-driving is turned on), the process proceeds to Step SC 4  as indicated with an arrow “YES”. When the reproduction mode is not on the key-driving mode (the key-driving is turned off), the process proceeds to Step SC 6  as indicated with an arrow “NO”. 
     At Step SC 4 , the note event (performance event EV or the driving event MV) that appears first from the beginning of the data in all the performance tracks PTD of the performance data PD selected at SA 3  in  FIG. 4  and in the driving track MTD corresponding to the performance track PTD selected as the driving target in the key-driving data MD is detected. Thereafter, the process proceeds to Step SC 5 . 
     At Step SC 5 , all the performance tracks PTD of the performance data PD selected at SA 3  in  FIG. 4  and in the driving track MTD corresponding to the performance track PTD selected as the driving target in the key-driving data MD are reproduced from the beginning data to the note event detected at Step SC 4  at high speed. Then, the process proceeds to Step SC 8 . 
     Moreover, events, etc. for executing initializing are stored in the normal performance data PD from the beginning of the data to 1 or 2 measure(s). The high speed reproduction according to the embodiment of the present invention is to reproduce those events at as high speed as possible regardless of the reproduction timing of the data for the 1 or 2 measure(s). 
     For example, in the electronic keyboard instrument  1  with a key driver, at least, events of 17 tracks including the tempo tracks can be read out and reproduced in one timing (1 tick). Moreover, plurality of the events in one track can be reproduced in one timing (1 tick). When the resolution is 1920 at this high speed reproduction, one or plurality of event(s) can be reproduced in 1/1920 of length of a quarter note by a simple calculation. In other words, over 1920 events can be reproduced at high speed for a time length of a quarter note. 
     At Step SC 6 , the note event (performance event EV) that appears first from the beginning of the data in all the performance tracks PTD of the performance track PD selected at SA 3  in  FIG. 4  is detected. Since the key driving is being turned off, it is not necessary to search in the key-driving data MD at this Step SC 5 . Thereafter, the process proceeds to Step SC 7 . 
     At Step SC 7 , all the performance tracks PTD of the performance data PD selected at Step SA 3  in  FIG. 4  are reproduced at high speed from the beginning of the data to the note event detected at Step SC 6 . Then the process proceeds to Step SC 8 . 
     At Step SC 8 , reproduction starts at normal speed. Reproduction at normal speed is reproduction according to the set tempo. Then, the process proceeds to Step SC 9  to finish the reproduction start process. 
       FIG. 9A  and  FIG. 9B  are schematic diagrams for explaining the reproduction starting process shown in  FIG. 8 . 
     For example, as shown in  FIG. 9A , the performance tracks  1  to  4  in the performance data PD are selected as reproduction targets. The performance tracks  1  and  2  are selected as the key-driving targets, and the driving tracks  1  and  2  corresponding to those driving target tracks are reproduced. In that case, when the key driving is turned on, the driving event MV 1  is detected at Step SC 4  because the first note event of the performance tracks  1  to  4  and the driving tracks  1  and  2  are detected at Step SC 4 . Then, events up to the driving event MV 1  is reproduced at high speed at Step SC 5 , as for the events after that, reproduction is started at normal speed at Step SC 8 . Moreover, when the key-driving is turned off, the performance event EV 1  is detected at Step SC 6  because only the performance tracks  1  to  4  will be the detecting targets of the first note event. Then, the events up to the event EV 1  are reproduced at high speed at Step SC 7 , as for the events after that, reproduction is started at normal speed at Step SC 8 . 
     Moreover, for example, as shown in  FIG. 9B , the performance tracks  1  to  4  in the performance data PD are selected as the reproduction targets, and the performance tracks  1  and  2  are selected as the key-driving targets. Then, the driving tracks  1  and  2  corresponding to those driving target tracks are reproduced. In the performance data shown in  FIG. 9B , events up to the performance event EV 4  are constantly reproduced at high speed regardless of ON/OFF of the key driving because the performance event EV 4  is the first note event in all the performance tracks and the driving tracks. Moreover, when the performance track  4  is selected as the driving target track, the event up to the driving event are reproduced at high speed because the driving event corresponding to the performance event EV 4  will be a note event to be reproduced. 
     As described in the above, the key-driving data MD of which timing is adjusted in advance is generated based on the performance data PD at Step SA 4  in  FIG. 4  before the reproduction process of the performance data PD to be executed at Step SA 6  and after that. Therefore, at the reproduction process from Step SA 6 , it is not necessary to adjust timing between the performance event and the key-deriving event. Therefore, quick start process can be easily executed because both key-driving data MD and the performance data PD are searched to detect the first note event, and only the events up to the detected note event are reproduced at high speed even if quick start is executed when the key-driving is turned on. 
     Moreover, since the key-driving data MD is not generated in advance in the conventional key-driving method, the timing is adjusted after detecting the first note event in the performance data, and reproduction timing of the key-driving note event corresponding to the detected performance note event is calculated, and the reproduction is performed at a high speed up to the calculated timing of the key-driving note event; therefore, the process that has to be executed when the quick start is instructed is complicated. 
     Moreover, according to the embodiment of the present invention with the above-described structure, a key of the keyboard can be certainly driven from the first performance event. Moreover, reproduction can be started quickly even if the first performance event is not used for the key-driving. 
       FIG. 10  is a flow chart showing the process executed at Step SA 10  in  FIG. 4  for processing the key-driving event just before paused position. This process is for certainly reproducing the key-driving event MV positioned (detected) after the position paused at Step SA 8  in  FIG. 4  when the corresponding performance event EV is positioned (detected) before the paused position. 
     The process for processing the key-driving event just before paused position is started at Step SD 1 . At Step SD 2 , the driving event MV just before the pointer position of the driving track MTD corresponding to the performance track PTD selected as the driving target from the performance data PD selected at SA 3  in  FIG. 4  (hereinafter, just called the target driving track MTD) is read out. Moreover, when there is a plurality of the target driving tracks MTD, the process from this Step SD 2  to the later-described Step SD 6  is executed for each target driving track MTD. 
     At Step SD 3 , it is judged whether or not a value of timing of event MV read at Step SD 2  or Step SD 5  added with the timing difference dT is not less than the present timing cT. When the value added with the timing difference dT is not less than the present timing cT, the performance event EV corresponding to the event MV read out at Step SD 2  or Step SD 5  exists after the present timing cT. Therefore, if the reproduction is started from the present timing cT, the key-driving event MV is not reproduced as for the performance event EV corresponding to the read event MV, and so a key is not driven. In this case, the process proceeds to Step SD 4  as indicated with an arrow “YES” in order to change starting timing of the reproduction, and the event MV read out at Step SD 2  or Step SD 5  is set to a step-back timing register. Thereafter, the process proceeds to Step SD 5 . When the event MV read out at Step SD 5  is set to the step-back timing register, the step-back timing register is overwritten. 
     When the value of the timing of the event MV added with the timing difference dT is read out at Step SD 2  or Step SD 5  is less than the present timing cT, there will be no problem to reproduce without changing the starting timing, and the process proceeds to Step SD 6  as indicated with an arrow “NO”. 
     At Step SD 5 , the event just before the event MV read out at Step SD 2  is read out. This is a process for repeatedly confirming that a value of the timing of the read event MV added with the timing difference dT becomes less than the present timing because the driving event MV corresponding to the performance event EV to be reproduced after the present timing cT is not limited to the event MV that is read out at Step SD 2 . Therefore, the process returns to Step SD 3  after reading out the event MV, and it is judged whether or not the value of the timing of the event MV read out at Step SD 5  added with the timing difference dT is not less than the present timing cT. 
     At Step SD 6 , it is judged whether or not the step-back reproduction is necessary. It is judged by checking whether or not the step-back timing (timing of the event MV read out at Step SD 2  or Step SD 5 ) is set to the step-back timing register set at Step SD 4 . When the step-back timing has been set, the process proceeds to Step SD 7  as indicated with an arrow “YES” because the step-back reproduction is necessary. When the step-back timing is not set, the process proceeds to Step SD 8  as indicated with an arrow “NO” to return to Step SA 11  in  FIG. 4  because the step-back reproduction is not necessary. 
     At Step SD 7 , only the target driving track MTD between the timing set in the step-back timing register and the present timing cT is reproduced. Thereafter, the process proceeds to Step SD 8  to return to SA 11  in  FIG. 4 . As described in the above, the driving event MV before the present timing cT and corresponding to the performance event EV after the present timing cT to be reproduced at Step SA 11  in  FIG. 4  can be selectively reproduced by reproducing only the target driving track MTD. Therefore, a key of the keyboard can be certainly driven as for the performance event EV even if the driving event MV corresponding to the performance event EV to be reproduced after the present timing cT is positioned before the present timing cT. 
     According to the process for processing the key-driving event just before paused position in the embodiment of the present invention as described in the above, it is judged whether or not a key-driving event MV corresponding to a performance event EV to be reproduced after the paused position exists before the paused position, and a key is driven in accordance with the key-driving event MV when it has been found before the paused position; therefore, the key can be certainly driven from the first performance event EV after restarting the reproduction. Moreover, when the corresponding key-driving event MV has not been found before the paused position, the reproduction is instantly restarted from the paused position; therefore, needless delay can be avoided. 
       FIG. 11A  and  FIG. 11B  are schematic diagrams for explaining the process for processing the key-driving event just before paused position shown in  FIG. 10 . 
       FIG. 11A  shows a case when the step-back reproduction is necessary. Reproduction of this performance data PD has been paused at the present timing cT 1 , and the pointer P 1  of the driving track is positioned at the driving event MV 3 . Moreover, the driving events MV 1  to MV 3  in the diagram respectively correspond to the performance events EV 1  to EV 3 . 
     When the process for processing the key-driving event just before paused position shown in  FIG. 10  is executed in the above-described condition, the event MV 2  positioned just before the MV 3  where the present pointer P 1  is positioned is read out. A value (number of ticks) of the timing of the event MV 2  added with the timing difference dT is a position of the event EV 2 ; however, it is positioned after the present timing cT 1  (number of ticks of the value of the timing of the event MV 2  added with the timing difference dT is larger than number of ticks of the present timing cT 1 ). That is, because an interval (the duration RT 1  in the diagram) between the present timing cT 1  and the event MV 2  is shorter than the timing difference dT, the process proceeds to Step SD 4 , and the timing of the event MV 2  is set to the step-back timing register. Thereafter, the event MV 1  jus before the event MV 2  is read out at Step SD 5 . Therefore, the process proceeds to Step SD 6  because an interval (the duration RT 2  in the diagram) between the present timing cT 1  and the event MV 1  is longer than the timing difference dT. Thereafter, the driving track is reproduced from the event MV 2  at Step SD 7 , and the reproduction after the present timing cT 1  is restarted at Step SA 11  in  FIG. 4 . 
       FIG. 11B  shows a case when the step-back reproduction is unnecessary and the same performance data PD as in  FIG. 11A  is reproduced. Reproduction of this performance data PD has been paused at the present timing cT 2 , and the pointer P 1  of the driving track is positioned at the driving event MV 3 . Moreover, the driving events MV 1  to MV 3  in the diagram respectively correspond to the performance events EV 1  to EV 3 . 
     When the process for processing the key-driving event just before paused position shown in  FIG. 10  is executed in the above-described condition, the event MV 2  positioned just before the MV 3  where the present pointer P 1  is positioned is read out. A value (number of ticks) of the timing of the event MV 2  added with the timing difference dT is a position of the event EV 2 , and it is positioned before the present timing cT 2  (number of ticks of the value of the timing of the event MV 2  added with the timing difference dT is smaller than number of ticks of the present timing cT 1 ). That is, because an interval (the duration RT 1  in the diagram) between the present timing cT 2  and the event MV 2  is longer than the timing difference dT, the process proceeds to Step SD 6  without setting the step-back timing register. Because the step-back timing register has not been set, the process is finished at Step SD 8 , and the reproduction after the present timing cT 2  is restarted at Step SA 11  in  FIG. 4 . Moreover, in this case, the driving event MV 1  is not read out. 
     Moreover, although the driving tracks MTD formed based on the performance data PD are recorded unitedly as driving data MD in the above-described embodiment, the formed driving tracks MTD may be recorded with the performance track PTD as a part of tracks in the performance data PD. 
     The present invention has been described in connection with the preferred embodiments. The invention is not limited only to the above embodiments. It is apparent that various modifications, improvements, combinations, and the like can be made by those skilled in the art.