Abstract:
A waveform output device includes a data reception unit which receives at least a part of a waveform pattern generation program transmitted from an external device connected to the data reception unit through a data line, the waveform pattern generation program being able to generate output data information and output time information, a tentative storage device which tentatively stores the waveform pattern generation program received from the data reception unit, a data processing unit which processes the waveform pattern generation program in the tentative storage device to generate the output data information and the output time information, and an output waveform generation unit which outputs waveform data to drive an electronic device based on the output data information and the output time information.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2004-107338, filed Mar. 31, 2004, the entire contents of which are incorporated herein by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a waveform output device which outputs waveform data in order to control actuators and electronic devices such as LED and a drive device into which the waveform output device is incorporated, particularly to the waveform output device and the drive device in which a module area can be decreased while development cost can be reduced. 
   2. Description of the Related Art 
   A control device which controls the actuators such as an electrostatic actuator, a piezoelectric actuator, and a stepping motor and the electronic devices such as LED using the waveform data is well known (Jpn. Pat. Appln. KOKAI Publication No. 8-140367).  FIG. 6  is a block diagram showing a configuration of an actuator system  1  which is an example of such control devices. The actuator system  1  includes an external device  2  to which a control signal is inputted, zoom operating units  3   a  to  3   c  in which operating sequences are stored, actuator drive units  4   a  and  4   b , autofocus operating units  5   a  and  5   b , a switching circuit  6 , and an actuator  7 . 
   In the actuator system  1 , the waveform data is outputted from the zoom operating units  3   a  to  3   c  in which the predetermined plural operating sequences are stored, the actuator drive units  4   a  and  4   b , and the autofocus operating units  5   a  and  5   b.    
     FIG. 7  is a block diagram showing the configuration of an actuator system which is another example of the control device. The actuator system  10  includes an external device  11  to which the control signal is inputted, an I/O interface  12 , a program ROM  13 , a program RAM  14 , a waveform output register  15 , MPU  16 , a switching circuit  17 , and an actuator  18 . 
   In the actuator system  10 , a predetermined waveform pattern is outputted from a waveform pattern output program recorded in the program ROM  13  and MPU  16 . Because an unexpected drive waveform cannot be generated only by the program ROM  13 , the data is set in the program RAM  14  from the external device  11 , and MPU  16  reads the RAM data to generate the waveform pattern. 
   However, because a nonvolatile memory for storing the drive waveform does not exist, it is difficult to store the unexpected drive waveform. In order to store the unexpected drive waveform, it is thought that the nonvolatile memory is additionally mounted on the actuator module or the nonvolatile memory of the external device is utilized as storage. 
   In the above waveform output device, there are the following problems. Namely, it is difficult to mount the nonvolatile memory on the actuator module, because cost of the actuator module is increased and a component mounting area is also increased. Because a dedicated communication line for connecting the external device and the actuator module is required in order to utilize the nonvolatile memory of the external device, modification of the external device is required, which results in the problem that development cost is increased. Further, in the case of the configuration in which one external device drives the plural actuators, the dedicated communication line is required for each actuator in the external device, which results in the problem that a wiring area is increased. 
   BRIEF SUMMARY OF THE INVENTION 
   In view of the foregoing an object of the invention is to be able to reduce production cost while being able to generate an unexpected drive waveform using a waveform pattern generation program. 
   In order to solve the above-described problem and achieve the object, according to embodiments of the present invention, there is provided a waveform output device comprising: a data reception unit which receives at least a part of a waveform pattern generation program transmitted from an external device connected to the data reception unit through a data line, the waveform pattern generation program being able to generate output data information and output time information; a tentative storage device which tentatively stores the waveform pattern generation program received from the data reception unit; a data processing unit which processes the waveform pattern generation program in the tentative storage device to generate the output data information and the output time information; and an output waveform generation unit which outputs waveform data to drive an electronic device based on the output data information and the output time information. 
   Further, according to embodiments of the present invention, there is provided a waveform output device comprising: a data reception unit which receives output data information and output time information transmitted from an external device connected to the data reception unit through a data line, the output data information and the output time information being generated based on a waveform pattern generation program; and an output waveform generation unit which outputs waveform data to drive an electronic device based on the output data information and the output time information. 
   According to embodiments of the present invention, the production cost can be reduced while the unexpected drive waveform can be generated using the waveform pattern generation program. 

   
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       FIG. 1  is an explanatory view showing an actuator system according to a first embodiment of the invention; 
       FIG. 2  is an explanatory view showing an operating flow of the actuator system; 
       FIG. 3  is an explanatory view showing an application example of the actuator system; 
       FIG. 4  is an explanatory view showing an actuator system according to a second embodiment of the invention; 
       FIG. 5  is an explanatory view showing the operating flow of the actuator system; 
       FIG. 6  is a block diagram showing an example of the conventional actuator system; and 
       FIG. 7  is a block diagram showing another example of the conventional actuator system. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  is a block diagram showing an actuator system  20  into which a waveform output device  60  according to a first embodiment of the invention is incorporated. 
   The actuator system  20  includes an electrostatic actuator  40 , a switching circuit  50 , the waveform output device  60 , an external device  70 , and a bus line  80 . The switching circuit  50  drives the electrostatic actuator  40 . The waveform output device  60  performs control by outputting the waveform data to the switching circuit  50 . The external device  70  transmits a waveform pattern generation program P to the waveform output device  60 . The waveform output device  60  and the external device  70  are connected to each other through the bus line  80 . The actuator system  20  constitutes a camera module which is built in the small electronic devices and the like. 
   The electrostatic actuator  40  includes a first moving element  41 , a second moving element  42 , a lower stator  43 , an upper stator  45 , and an image pickup element  44 . The first moving element  41  holds a lens L 1 , and an electrode surface is formed in the first moving element  41 . The second moving element  42  holds a lens L 2 , and the electrode surface is formed in the second moving element  42 . An electrode substrate is provided in the lower stator  43  and the upper stator  45 . An image is focused onto the image pickup element  44  through the lenses L 1  and L 2 . 
   The switching circuit  50  has a function of converting the inputted waveform signal into voltage to provide the voltage to the electrode surface of the first moving element  41 , the electrode surface of the second moving element  42 , and the electrode substrate of the lower stator  43 , and the electrode substrate of the upper stator  45 . Namely, 1 and 0 of each bit in the drive pattern correspond to High and Low of the voltage provided to the electrode. 
   The waveform output device  60  includes MPU (waveform data generation unit)  61 , a program RAM  62 , a control command register  63 , an output register  64 , an output waveform generation unit  65 , and an I/F module (data reception unit)  66 . The waveform pattern generation program P is tentatively stored in the program RAM  62 . The output waveform generation unit  65  converts the waveform data into drive data of electromechanical transducer element. 
   The external device  70  includes an external MPU  71 , a program RAM/ROM  72 , a nonvolatile memory  73 , a control command register  74 , and an I/F module (data transmission unit)  75 . The external MPU  71  determines a register value or data on the memory to perform the control. The waveform pattern generation program P is stored in the program RAM/ROM  72 . The waveform pattern generation program P is stored in the nonvolatile memory  73  such as a flash memory. The control command register  74  performs mapping of the control signal from a user. The I/F module  75  converts the output data into the data in a form of a communication format of a general-purpose bus. 
   The actuator system  20  configured as above is operated according to an operating flow shown in  FIG. 2 . When the external device  70  is turned on, the external MPU  71  is activated (ST 10 ). The external MPU  71  copies the waveform pattern generation program P stored in the nonvolatile memory  73  in a storage area of the program RAM  62  in the waveform output device  60  through the I/F module  75  (ST 11 ). Then, MPU  61  in the waveform output device  60  is activated to generate the waveform data (output data information and output time information) (ST 12 ). 
   The waveform pattern generation program P will be described. The waveform pattern generation program P includes a program body (program body to generate waveform pattern) and a monitoring program. In the program body, a computing procedure of generating the waveform pattern is programmed. The monitoring program monitors a control register and data with which the program body generates the waveform pattern. For example, a database in which output data information and output time information of elementary actions of the plural patterns are stored or numerical data for computing the output data information and output time information of the elementary actions can be used as the data with which the program body generates the waveform pattern. 
   The relationship between the waveform pattern generation program P and the program RAM/ROM  72  and nonvolatile memory  73  will be described in detail. Among the pieces of data used for the generation of the waveform pattern included in the waveform pattern generation program P, the information necessary to respond to an unexpected drive waveform is stored in the nonvolatile memory  73 . It is possible that the information which is not necessary to respond to the unexpected drive waveform (data or program used commonly for any waveform) is stored in the nonvolatile memory  73 . Alternatively, the information which is not necessary to respond to the unexpected drive waveform may be stored as ROM data in the program RAM/ROM  72 . It is possible that the drive waveform data which is primarily utilized by the waveform pattern generation program P is stored in RAM data in the program RAM/ROM  72 . 
   For example, in the case of the database in which the output data information and output time information of elementary actions of the plural patterns are stored, the database is usually stored in the nonvolatile memory  73 . In the case of the numerical data for computing the output data information and output time information of the elementary actions, the numerical data itself or variable value of a part of the pieces of numerical data is stored in the nonvolatile memory  73 . 
   The waveform pattern generation program P and the program RAM/ROM  72  and nonvolatile memory  73  can also have the following configuration. 
   Default data (initial data) of the data used for waveform pattern generation in the waveform pattern generation program P is stored in the ROM area in the program RAM/ROM  72 . When a user externally temporarily changes the data used for the waveform pattern generation, the default data is stored in the RAM data in the program RAM/ROM  72 . When the user saves the changed data, the user copies the data from the program RAM/ROM  72  to the nonvolatile memory  73 . Then, the user defines of which area the waveform pattern generation program P stored in the memory is preferentially utilized. Usually, the program RAM has the first priority, the nonvolatile memory has the second priority, and the program ROM has the third priority. 
   According to the above rule, when the user does not rewrite the waveform pattern nor exist the data in the nonvolatile memory  73 , the default drive waveform is outputted. When the user does not rewrite the waveform pattern and the user saves the waveform data in the nonvolatile memory  73 , the waveform pattern generation program P stored in the nonvolatile memory  73  is utilized. When the user rewrites the waveform pattern, the rewritten waveform pattern is outputted. 
   Thus, the method of storing the information which is not necessary to respond to the unexpected drive waveform in the waveform pattern generation program P is determined by the program configuration, the storage capacities of the program RAM/ROM  72  and nonvolatile memory  73 , and the like. 
   Whether a value of the control command register  74  is changed or not is determined (ST 13 ). When the value of the control command register  74  is changed, the register data of the control command register  74  is transferred to the control command register  65  (ST 14 ). At this point, the data of the control command register  74  is tentatively converted (encoded) into the general-purpose format such as IIC format by the I/F module  75  in the external device  70 , the data is converted (decoded) into the register data format again by the I/F module  66  in the waveform output device  60 , and the transfer is performed. 
   On the other hand, the waveform pattern generation program P executed in the waveform output device  60  determines the change of value of the control command register  63  of the waveform output device  60  (ST 20 ), and the program determines whether the value of the control command register  63  is applicable to a drive waveform output command or not (ST 21 ). Then, the waveform data (output data information and output time information) is set in the output register  64  (ST 22 ). 
   When the waveform data is set in the output register  64 , for example, the waveform data is converted into the drive data for the electrostatic actuator  40  by the output waveform generation unit  65  in the following manner. Namely, in the output waveform generation unit  65 , digital-to-analog conversion is performed based on the output data information stored in the output register  64 , and the waveform signal is formed to output the waveform signal for a drive time corresponding to the output time information. 
   For example, the waveform signal is formed by a data string of 12 bits, and each bit outputs Low or High voltage. The voltage is about 2.5V in the High state, and the High voltage is sufficiently small relative to the drive voltage of the electrostatic actuator  40 . For example, the drive voltage of the electrostatic actuator  40  is 100V. A voltage boost device (not shown) is the device which generates the drive voltage of the electrostatic actuator  40  and is connected to the switching circuit  50 . When each bit of the output waveform generation unit  65  is in the High state, the switching circuit  50  outputs the drive voltage. The output of the switching circuit  50  becomes the output to the electrostatic actuator  40 . 
   As described above, according to the actuator system  20 , the waveform pattern generation program P is stored in the nonvolatile memory  73  of the external device  70 , transferred to the waveform output device  60  as necessary, and then executed. Therefore, it is not necessary to provide the nonvolatile memory on the side of the waveform output device  60 , and the production cost can be suppressed. In many cases, the nonvolatile memory is mounted on the external device  70 , so that the production cost is not particularly increased. 
     FIG. 3  shows the configuration in which the plural waveform output devices  60  are controlled from one external device  70  to drive the plural electrostatic actuators  40 . The waveform output device  60 , the switching circuit  50 , and the electrostatic actuator  40  are provided in each drive module K. The wiring can be shortened by using the bus line  80 . Identification data is set in each drive module K. The external device  70  can transmit the data to an arbitrary drive module by specifying the identification data as a transmitted party. As the identification data of the transmitted party, a slave address can be utilized in the case of, for example, an IIC bus. In the configuration shown in  FIG. 3 , the production cost of the waveform output device  60  can also be suppressed. 
   In the embodiment, it has been explained that the waveform pattern generation program P which is copied in the storage area of the program RAM  62  through the I/F module  75  includes the program body for generating the waveform pattern and the monitoring program for monitoring the control register and the data with which the program body generates the waveform pattern. However, the waveform pattern generation program P which is copied in the storage area of the program RAM  62  through the I/F module  75  does not always include all of the program body for generating the waveform pattern and the monitoring program for monitoring the control register and the data with which the program body generates the waveform pattern. 
   For example, It is possible that a part of the waveform pattern generation program P is copied in the program RAM  62  through the I/F module  75  and another part of the waveform pattern generation program P stored in the ROM area in MPU  61  is copied in the program RAM  62  not through the I/F module  75 . It is possible that a part of the waveform pattern generation program P includes a part of the program body for generating the waveform pattern and another part of the waveform pattern generation program P includes the monitoring program for monitoring the control register and the data with which the program body generates the waveform pattern. 
   In Step ST 21 , it is also possible that the waveform data set in the output register  64  corresponding to the drive direction are changed by setting drive direction flag data and a drive waveform output command in a control command register value. 
     FIG. 4  is a block diagram showing an actuator system  21  into which a waveform output device  90  according to a second embodiment of the invention is incorporated. In  FIG. 4 , the same functional component as  FIG. 1  is indicated by the same numeral, and the detail description is not repeated here. 
   The actuator system  21  includes the electrostatic actuator  40 , the switching circuit  50 , a waveform output device  90 , an external device  100 , and the bus line  80 . The switching circuit  50  drives the electrostatic actuator  40 . The waveform output device  90  performs the control by outputting the waveform data to the switching circuit  50 . The external device  100  transmits a waveform pattern generation program P to the waveform output device  90 . The waveform output device  90  and the external device  100  are connected to each other through the bus line  80 . The actuator system  21  constitutes the camera module which is built in the small electronic devices and the like. 
   The waveform output device  90  includes an I/F module (data reception unit)  91 , an output register  92 , and an output waveform generation unit  93 . The output waveform generation unit  93  converts the waveform data into drive data of electromechanical transducer element. 
   The external device  100  includes an external MPU  101 , a program RAM/ROM  102 , a nonvolatile memory  103 , a control command register  104 , and an I/F module (data transmission unit)  105 . The external MPU  101  determines the register value to perform the control while interpreting and executing the waveform pattern generation program P. The waveform pattern generation program P is stored in the program RAM/ROM  102 . The waveform pattern generation program P is stored in the nonvolatile memory  103  such as the flash memory. The control command register  104  performs the mapping of the control signal from the user. The I/F module  105  converts the output data into the data in the form of the communication format of the general-purpose bus. 
   The input data and the output data between the waveform output device  90  and the external device  100  is converted into the general-purpose bus communication format by the I/F module  105 . For example, when the external MPU  101  in the external device  100  outputs the waveform data, the I/F module  105  tentatively converts the register data into the data in the form of the general-purpose communication format, the data is converted into the register data again by the I/F module  91  in the waveform output device  90 , and the register data is set in the output register  92 . When the waveform data is set in the output register  92 , for example, the waveform data is converted into the drive data for the electrostatic actuator  40  by the output waveform generation unit  93  in the following manner. Namely, in the output waveform generation unit  93 , the digital-to-analog conversion is performed based on the output data information stored in the output register  92 , and the waveform signal is formed to output the waveform signal for a drive time corresponding to the output time information. 
   For example, the waveform signal is formed by a data string of 12 bits, and each bit outputs the Low or High voltage. The HIGH voltage is about 2.5V, and is sufficiently small relative to the drive voltage of the electrostatic actuator  40 . For example, the drive voltage of the electrostatic actuator  40  is 100V. 
   The voltage boost device (not shown) is the device which generates the drive voltage of the electrostatic actuator  40  and is connected to the switching circuit  50 . When each bit of the output waveform generation unit  65  is in a High state, the switching circuit  50  outputs the drive voltage. The output of the switching circuit  50  becomes the output to the electrostatic actuator  40 . 
   The actuator system  21  configured as above is operated according to the operating flow shown in  FIG. 5 . When the external device  100  is turned on, the waveform pattern generation program P is transferred from the nonvolatile memory  103  to the storage area of the program RAM/ROM  102  in the external device  100 . When the transfer is completed, the program of the external device  100  is started to generate the waveform data (ST 30 ). Whether the value of the control command register  104  is changed or not is determined (ST 31 ), and whether the value of the control command register  104  is applicable to the drive waveform output command or not is determined (ST 32 ). Then, the waveform data is set in the output register. 
   As described above, according to the actuator system  21 , the waveform pattern generation program P is stored in the nonvolatile memory  103  of the external device  100 , the waveform pattern is transferred to the waveform output device  90  through the bus line  80 , and the waveform pattern is outputted. Therefore, it is not necessary to provide the nonvolatile memory on the side of the waveform output device  90 , and the production cost can be suppressed. Further, it is not necessary to provide MPU which is the data processing device, so that the configuration can be simplified and the module area can be decreased. In many cases, the data processing device such as the external MPU  101  is incorporated in the external device  100 , and the data processing device can be utilized, so that it is not necessary to additionally improve the external device  100 . 
   Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.