KR100294213B1 - Step Motor Control Method and Apparatus_ - Google Patents

Abstract

The present invention includes a step motor for providing a driving force for moving and scanning a scanning module with respect to an original placed on a flat plate, and a storage medium for storing one acceleration / deceleration pattern and final speed data for each resolution, and at least two resolutions. A flat bed type scanner capable of selecting: detecting a deceleration pattern and a number of steps to which an acceleration / deceleration pattern is applied and final velocity data of a specified resolution corresponding to an arbitrary resolution designated by a user; Applying the detected acceleration / deceleration speed data by the number of steps to accelerate the step motor; If the current step number exceeds the step number, the step motor is driven using the designated final speed data.

Therefore, according to the present invention, the capacity of data to be stored in the storage medium is reduced by storing one acceleration / deceleration pattern and the final speed data corresponding to each resolution without having to store a plurality of acceleration / deceleration patterns for each resolution. And, this can reduce the capacity of the storage medium, there is an advantage that can reduce the manufacturing cost.

Description

Step motor control method and apparatus

The present invention relates to a step motor control method and apparatus, and more particularly, to a step motor for reciprocating a scanning module of a flat bed type scanner for moving and scanning a scanning module with respect to an original placed on a flat plate. In the control of the rotation state of the step motor control method and apparatus for controlling the rotation state of the step motor by using a reference pattern and the acceleration and deceleration data of the preset scanning module for each resolution.

In general, a flatbed scanner refers to a device that scans data recorded on an original surface while fixing the original on a flat plate and moving the scanner module from the upper side to the lower side or from the left side to the right side of the original. The flatbed scanner includes a step motor for transferring a scanning module therein, and controls the rotation speed of the motor according to a predetermined acceleration / deceleration pattern in order to maintain a constant scanning speed for an arbitrary resolution. . That is, the scanning module should be transferred at various speeds according to the resolution specified by the user. In order to stabilize the transfer process of the scanning module, various types of driving patterns according to various driving speeds should be applied.

In the past, the following two methods were used to cope with various speeds according to user-specified resolutions.

First, the acceleration / deceleration pattern for the driving speed of each resolution is stored, and if the user designates the resolution, the acceleration / deceleration pattern corresponding to the designated resolution is detected and applied to the step motor control circuit, thereby performing the scanning operation of the designated resolution.

In this manner, as shown in Fig. 1, an acceleration curve corresponding to each resolution is prepared in order to drive the step motor in an optimal state corresponding to each resolution. Based on this acceleration curve, the number of acceleration steps is determined in order to accelerate to the final speed in a constant step. The speed data corresponding to each acceleration step is generated as time data, and the step motor is operated one step at this time interval. Apply by making a table. For example, in the acceleration curve as shown in FIG. 1, in the case of the 75DPI (Dot per Inch) acceleration pattern, the driving speed table corresponding to each resolution is formed by setting the number of acceleration steps in 20 steps. Such drive speed data is possible by a simple calculation formula, but since the drive speed data corresponding to each resolution must be stored separately, the data amount is enormous.

Second, the speed of the step motor is specified and operated in only a few steps, and the resolution is adjusted by making image data valid (taken as normal data) or invalid (discarded image data) for the scanning line.

However, according to the conventional flatbed scanner, the following problems occur.

First, when the acceleration / deceleration pattern for the driving speed of each resolution is stored and the user designates the resolution, the acceleration / deceleration pattern corresponding to the designated resolution is detected and applied to the step motor control circuit. The storage capacity increases as the number of resolutions increases, so the manufacturing cost increases as a large storage medium must be built.

Second, when the speed of the step motor is specified and operated in a few steps, and the resolution is adjusted by validating or invalidating the image data for the scanning line, the entire content of the original is not reflected in the output image information. Will occur.

Accordingly, an object of the present invention is to solve such problems, and an object of the present invention is to store the final velocity data that can be applied to all resolutions based on one acceleration / deceleration pattern on a storage medium, and to specify a resolution designated by a user. The present invention provides a step motor control method capable of performing a simple and stable control process by detecting only the final speed data corresponding to and controlling the rotation speed of the step motor.

In addition, another object of the present invention is to provide a step motor control apparatus for performing the above step motor control method.

1 is a waveform diagram showing an acceleration / deceleration pattern used in a step motor control circuit in a conventional flatbed scanner.

2 is a schematic block diagram of a flatbed scanner applied to the present invention,

3 is a detailed block diagram of a step motor control circuit according to a first embodiment of the present invention;

4 is an operation timing diagram according to the step motor control process of the present invention,

5 is a waveform diagram showing velocity data applied to the present invention corresponding to each resolution;

6 is a detailed block diagram of a step motor control circuit according to a second embodiment of the present invention.

<Description of the code | symbol about the principal part of drawing>

101: central processing unit 102: controller

116: Roman 117: Step motor

200: step motor control circuit 201: address buffer

202: acceleration ram 203: deceleration ram

204 and 205: data buffers 206, 217 and 218: control signal generator

207: address counter 208: settable counter

209: system clock generator 210: interrupt generator

211: up / down counter 212: register

213: full step pattern memory 214: half step pattern memory

215: counter 216: comparator

219: pattern memory

A feature of the present invention for achieving the above object is a step motor for providing a driving force for scanning by moving the scanning module with respect to the document placed on the plate, one acceleration and deceleration pattern and the final speed data for each resolution is stored A flat-bed scanner comprising a storage medium and capable of selecting at least two resolutions, the flat-bed scanner comprising: a step number to which an acceleration / deceleration pattern and an acceleration / deceleration pattern are applied according to an arbitrary resolution designated by a user, and final velocity data of the specified resolution Detect; Applying the detected acceleration / deceleration speed data by the number of steps to accelerate the step motor; When the current number of steps exceeds the number of steps, the step motor is driven using the designated final speed data.

Here, the acceleration / deceleration pattern is an acceleration / deceleration pattern corresponding to the lowest resolution.

On the other hand, another feature of the present invention includes a step motor for providing a driving force for scanning by moving the scanning module with respect to the document placed on the flat plate, and a storage medium for storing one acceleration / deceleration pattern and the final speed data for each resolution A flatbed scanner capable of selecting at least two resolutions, the flatbed scanner comprising: a RAM configured to store acceleration / deceleration patterns and final speed data for each resolution stored in a storage medium; An address buffer for providing an address for storing the acceleration / deceleration pattern and the final speed data for each resolution in the RAM; A data buffer for temporarily buffering the acceleration / deceleration pattern and the final speed data in the RAM; A register storing various information necessary for driving the step motor; An address counter which provides an address for detecting the acceleration / deceleration pattern and the final speed data from the RAM corresponding to the resolution designated by the user when the step motor is driven; A configurable counter which receives the acceleration / deceleration pattern and the final speed data corresponding to the resolution designated by the user from the RAM and down counts one step according to the clock provided from the clock generating means; An interrupt generator for generating an interrupt signal each time the count value of the settable counter becomes " 0 "; Receives the interrupt signal output from the interrupt generator as a clock and performs the up and down counting operation according to the rotation direction of the step motor specified in the register in response to the acceleration / deceleration pattern specified by the user. It includes an up / down counter that controls the rotational speed of.

Here, the RAM includes an acceleration RAM for storing the acceleration pattern and the final speed data of each of the acceleration and deceleration pattern and the final speed data for each resolution; It includes a deceleration RAM for storing the deceleration pattern of the acceleration and deceleration pattern and the final speed data for each resolution.

On the other hand, another feature of the present invention is a step motor for providing a driving force for scanning by moving the scanning module with respect to the document placed on the plate, and a storage medium that stores one acceleration and deceleration pattern and the final speed data for each resolution For flatbed scanners that include at least two resolutions:

RAM for storing the acceleration / deceleration pattern and the final speed data for each resolution stored in the storage medium; An address counter for storing or detecting acceleration / deceleration patterns and final speed data for each resolution in the RAM to control the step motor; A data buffer for temporarily buffering the acceleration / deceleration pattern and the final speed data in the RAM; A counter for counting a clock provided from the clock generating means; A comparator for comparing the counting value of the counter with the acceleration / deceleration pattern stored in the RAM and the data value of the acceleration / deceleration pattern and the final speed data designated by the user and outputting a predetermined control signal according to the result; A register storing various information necessary for driving the step motor; An up / down counter which generates an address while performing up counting and down counting operations according to the signal output from the comparator and the rotation direction information output from the register; And a control signal generator for increasing and decreasing the address counting value provided to the RAM in the address counter according to the output signal of the comparator and the output signal of the register.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the elements of each drawing, it should be noted that the same elements are denoted by the same reference numerals as much as possible even if they are displayed on different drawings. In addition, in the following description, many specific details are shown, such as specific blocks or components of circuits, which are provided to help a more general understanding of the present invention, and the present invention may be practiced even if these specific details are removed or modified. It will be obvious to those of ordinary skill in the art. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

2 is a schematic block diagram of a flatbed scanner applied to the present invention.

The schematic structure of the flatbed scanner with reference to FIG. 2 will now be described.

The central processing unit 101 controls the system as a whole according to a predetermined program.

The controller 102 generates a timing signal for controlling the function of each component under control of the main clock and the central processing unit 101, and generates a corresponding control signal according to the request of each component. Here, the controller 102 includes address generators 102a and 102b for generating address information for storing temporary data generated during signal processing.

The lamp control circuit 103 controls the lighting state of the lamp 104 which scans light onto the original surface.

The sensor driver 105 controls an image sensor 106 (for example, using a charge coupled device (CCD)) which photoelectrically converts the density of an image recorded in an original into an electrical signal and outputs the same.

The amplifier 107 amplifies the electric image signals R, G, and B output from the image sensor 106 to a size suitable for signal processing.

The analog / digital converter 108 converts the analog image signal amplified by the amplifier 107 into a digital form.

The correction memory 109 temporarily stores the image information in a predetermined area according to the address information output from the address generator 102a to perform a process of correcting the image information digitized by the analog / digital converter 108. .

The gamma correction unit 110 corrects the image information stored in the correction memory 109. At this time, in order to maintain the image information obtained in the scanning process close to the image information recorded in the actual document, the correction data for each characteristic of the system is added. Correct the image information accordingly.

The image memory 111 stores the image information corrected by the gamma correction unit 110 in the predetermined area in accordance with the address information output from the address generator 102b.

The interface unit 112 interfaces data transmission / reception states with the computer 113. That is, when a request for the transfer of image data is received from the computer 113, the interface unit 112 transfers the image information output from the image memory 111 to the computer 113, and various controls transmitted from the computer 113. The signal and the command are transmitted to the central processing unit 101.

The clock generator 114 generates a system clock having a predetermined frequency required by the system. In this case, a system clock having various types of frequencies required by the system may be generated through the dispensing process.

The sensor unit 115 detects the presence or absence of a document.

The ROM 116 stores various program data to be executed by the central processing unit 101. In particular, the ROM 116 stores acceleration / deceleration data for speed control of the step motor 117.

The RAM 118 temporarily stores temporary data generated while the system executes various programs.

The step motor control circuit 200 controls the rotation state, the rotation direction, and the acceleration / deceleration state of the step motor 117 under the control of the central processing unit 101.

<1st Example of this invention>

3 shows a detailed block diagram of the step motor control circuit according to the first embodiment of the present invention, and FIG. 4 shows an operation timing diagram according to the step motor control process of the present invention. A waveform diagram showing velocity data applied to the present invention corresponding to the resolution is shown.

The detailed configuration of the step motor control circuit 200 according to the first embodiment of the present invention will be described with reference to FIG. 3.

The address buffer 201 specifies an address for storing the acceleration / deceleration table data (final speed data) stored in the ROM 116 in the acceleration ram 202 and the deceleration ram 203.

The first and second data buffers 204 and 205 temporarily buffer the acceleration / deceleration table data stored in the ROM 116.

The control signal generator 206 is directly controlled by the controller 102 in the system and generates a control signal for operating each component in the step motor control circuit 200.

The address counter 207 provides an address for detecting data stored in the acceleration ram 202 and the deceleration ram 203 corresponding to the resolution specified by the user when driving the step motor 117.

The acceleration ram 202 and the deceleration ram 203 store speed data regarding final acceleration and deceleration for each resolution that can be designated by a user.

The settable counter 208 receives the acceleration / deceleration data from the acceleration ram 202 and the deceleration ram 203 and down counts them by one step according to the clock input from the system clock generator 209.

The interrupt generator 210 generates an interrupt signal whenever the counting value of the configurable counter 208 becomes " 0 ".

The up / down counter 211 receives an interrupt signal output from the interrupt generator 210 as a clock and performs up counting and down counting operations according to the rotation direction of the step motor 117 corresponding to the specified pattern.

The register 212 stores various kinds of information related to the control of the step motor 117.

The full step pattern memory 213 and the half step pattern memory 214 correspond to the full step pattern corresponding to the driving state of the flatbed scanner according to the resolution specified by the user. Each half-step pattern is stored.

Referring to the operation of the first embodiment of the present invention having such a configuration as follows.

First, as shown in FIG. 2, the flatbed scanner is configured based on a constant value set from the central processing unit 101, the clock generator 114, and the central processing unit 101 to control the system as a whole. The controller 102 generates a timing signal for controlling each function and controls the required signal appropriately at a necessary time.

The sensor driver 105 is a circuit for controlling the image sensor 106 which outputs the density of an image as an electrical signal through a photoelectric conversion operation. The electrical signal output from the image sensor 106 is converted into color components R, G, and B and input to the amplifier 107, and each image signal amplified to a certain level by the amplifier 107 is analog / It is input to the digital converter 108.

The image signal input to the analog / digital converter 108 is converted into digital data, and performs a task for removing distortion of a signal generated according to device characteristics during photoelectric conversion.

The data stored in the correction memory 109 is extracted and stored in accordance with the system characteristics before scanning the image, and then outputs the appropriate correction data under the control of the controller 102 when the actual scanning operation is performed. Corrective action is taken to improve the image quality.

The digitized data is stored in the image memory 111 after performing the gamma correction operation by the gamma correction unit 110, and the computer 113 through the interface unit 112 at the request of the computer 113 at a certain point in time. Is sent to. That is, the data stored in the image memory 111 is transferred to the interface unit 112 according to the address control of the controller 102, and the communication operation with the computer 113 is performed by the control of the central processing unit 101.

The sensor unit 115 is configured such that the optical output of the lamp 104 driven according to the signal output of the lamp control circuit 103 under the control of the central processing unit 101 is reflected to the original and input to the image sensor 106. The location of the module is determined, and the detected information is transmitted to the CPU 101.

In addition, the flatbed scanner includes a step motor 117 that is a means for transferring the optical module, the step motor 117 is driven in accordance with the signal provided from the step motor control circuit 200.

Meanwhile, the operation of the step motor control circuit will be described with reference to FIGS. 4 and 5.

Acceleration and deceleration table data (see FIG. 5) for any resolution stored in ROM 116 are sequentially applied to acceleration ram 202 and deceleration ram 203 by address buffer 201 and first data buffer 204. Stored. Here, the acceleration / deceleration table data basically stores only data for an acceleration pattern corresponding to the lowest resolution (that is, maximum speed) as shown in FIG. Take advantage. For example, when a scanning operation is to be performed at a resolution of 230 DPI, an acceleration pattern is applied to an acceleration straight line of 75 DPI until 11 steps, and the final speed of 230 DPI is performed from 12 steps to 20 steps. In addition, when scanning at 390 DPI, the acceleration speed of 75 steps is used up to 7 steps and the final speed of 390 DPI is used from 8 steps to 20 steps, thereby enabling acceleration of a desired speed. Therefore, compared to the conventional case, the capacity of data to be stored in the ROM 116 is reduced and can be utilized over the entire resolution through one acceleration / deceleration table.

Subsequently, the full-step / half-step driving pattern data stored in another area of the ROM 116 is stored in the corresponding pattern memory 213 as the address buffer 201 designates an address and the second data buffer 205 transfers the data. 214). When the preparation process is completed, the preparation for the scanning operation is completed. When the scanning command is received from the computer 113, the central processing unit 101 drives the register 212 in a driving method (full step or half step), rotation direction, and speed. Pattern (acceleration, constant speed, deceleration) signals are stored at the appropriate timing at the appropriate time to perform the desired operation.

For example, referring to the operation timing diagram of FIG. 4, first, all initial values of the register 212 are set to "0" in the stop state. When the scanning command is received, the scanning signal, the acceleration signal, and the stop signal are all set to "1". This means the transition from the stop state to the acceleration state.

When the value of the register 212 (scanning signal = 1, acceleration signal = 1, stop signal = 1) is set, the acceleration RAM 202 is enabled and accelerated according to the address provided by the address counter 207. The data of the RAM 202 is output. At this time, since the initial value is "0", the data of address "0" stored in the acceleration RAM 202 is set in the settable counter 208, and the counting value of the settable counter 208 is the system clock generator 209. Decreases by "1" depending on the system clock input from the system. When the count value of the settable counter 208 becomes "0", the interrupt generator 210 generates an interrupt signal in the form of a pulse, and counts the up / down counter 211 and the address counter 207 according to the pulse. The value is increased by "1".

When the counting value of the address counter 207 increases by "1", the address counter 207 sets the data of the "1" address stored in the acceleration RAM 202 to the settable counter 208 and the up / down counter 211. ) Is a result of the pattern value stored in the full-step pattern memory 213 or the half-step pattern memory 214, and finally the step motor is moved one step.

Thereafter, when the counting value of the settable counter 208 becomes "0", the above-described operation is repeatedly performed. At this time, the counting value of the address counter 207 is sequentially increased according to the interrupt pulse generated by the interrupt generator 210. This operation is performed according to the control of the central processing unit 101 when the acceleration step number is determined according to the speed according to the set resolution, that is, the scanning operation is performed when the scanning command is received. 212 is set to acceleration "0" and constant speed "1", and the step motor 117 switches to the constant speed state. At this time, the address of the acceleration RAM 202 is not changed, and the scanning operation of the image is performed after passing through the stabilization period by repeatedly performing a constant address for a certain step.

Thereafter, when the scanning operation is performed by the predetermined amount (step number), the step motor 117 is switched to the deceleration state. That is, when the register 212 is set to the constant speed "0" and the deceleration "1" under the control of the central processing unit 101, the deceleration ram 203 is enabled and the address of the deceleration ram 203 is "0". Becomes In this state, the deceleration data output at address " 0 " of the deceleration ram 203 is set in the settable counter 208, and the settable counter 208 of the settable counter 208 according to the system clock provided from the system clock generator 209. The counting value is decreased by "1".

Then, when the counting value of the settable counter 208 becomes "0", the interrupt generator 210 generates an interrupt signal in the form of a pulse, and the counting value of the address counter 207 is "1" according to this interrupt pulse. Increases by

When the data at address "1" is set in the settable counter 208, the counting value of the up / down counter 211 is increased to set the step motor (set in the full step pattern memory 213 or the half step pattern memory 214). As the driving pattern of 117 is outputted, the step motor 117 advances one step. When this operation proceeds for a certain step and the deceleration state is completed, the register 212 is set to deceleration " 0 " and stop " 0 " so that the step motor 117 is stopped.

Thereafter, in the state where the register 212 sets the rotation direction of the step motor 117 to "1", if the above steps are repeated, the step motor 117 performs reverse rotation. As a result, by repeating the above process, it is possible to control the image scanning operation for the preset area.

On the other hand, the full-step pattern memory 213 and the half-step pattern memory 214 are selectively operated according to the user's setting to drive the step motor 117. In the full-step mode (scanning according to the predetermined resolution) The driving pattern stored in the full-step pattern memory 213 is output in the case of performing a job, and the half-step pattern memory 214 in the case of the half-step mode (when scanning is performed at twice the resolution). Is stored in the driving pattern.

<2nd Example of this invention>

6 shows a detailed block diagram of the step motor control circuit according to the second embodiment of the present invention.

Referring to Figure 6 describes a step motor control circuit according to a second embodiment of the present invention.

The acceleration ram 202 and the deceleration ram 203 store the acceleration data table and the deceleration data table, respectively.

The address counter 207 stores or detects data of the acceleration ram 202 and the deceleration ram 203 for controlling the step motor 117, and stores the driving pattern of the step motor 117.

The counter 215 counts the system clock provided from the system clock generator 209.

The comparator 216 compares the counting value of the counter 215 with the data values of the acceleration ram 202 and the deceleration ram 203 and outputs a predetermined signal corresponding to the result.

The up / down counter 211 generates an address while performing an up counting or down counting operation according to the signal output from the comparator 216 and the rotation direction signal output from the register 212. .

The first and second data buffers 204 and 205 temporarily buffer the acceleration / deceleration table data stored in the ROM 116.

The first control signal generator 217 is an address counting value provided to the acceleration ram 202 and the deceleration ram 203 at the address counter 207 according to the output signal of the comparator 216 and the output signal of the register 212. To increase, stop, or reset.

The second control signal generator 218 resets the counter 215 and the up / down counter 211, or resets the system clock generated from the system clock generator 209 to the counter 215 and up / down counter 211. To provide.

The acceleration ram 202 and the deceleration ram 203 store speed data regarding final acceleration and deceleration for each resolution that can be specified by a user.

The register 212 stores various kinds of information related to the control of the step motor 117.

The pattern memory 219 is composed of a full step pattern memory and a half step pattern memory, as mentioned in FIG. 3, and corresponds to a flatbed scanner corresponding to a resolution specified by a user. The full step pattern and the half step pattern corresponding to the driving state are stored, respectively.

The operation of the second embodiment of the present invention having such a configuration will be described below with reference to FIGS. 4 and 5.

The acceleration / deceleration table data for any resolution stored in the ROM 116 is sequentially stored in the acceleration RAM 202 and the deceleration RAM 203 by the address counter 207 and the first data buffer 204. Thereafter, the full-step / half-step driving pattern data stored in another area of the ROM 116 is determined by the driving method set in advance by the program according to the resolution specified by the user. Stored at 219. When the preparation process is completed, the preparation for the scanning operation is completed. When the scanning command is received from the computer 113, the central processing unit 101 transmits a rotation direction and a speed pattern (acceleration, constant speed, deceleration) signal to the register 212. By saving at the right time and at the right time, you can perform the desired operation.

For example, referring to the operation timing diagram of FIG. 4, first, all initial values of the register 212 are set to "0" in the stop state. When the scanning command is received, the scanning signal, the acceleration signal, and the stop signal are all set to "1". This means the transition from the stop state to the acceleration state.

When the value of the register 212 (scanning signal = 1, acceleration signal = 1, stop signal = 1) is set, the acceleration RAM 202 is enabled and accelerated according to the address provided by the address counter 207. The data of the RAM 202 is output. At this time, since the initial value is "0", data of address "0" stored in the acceleration RAM 202 is input to the comparator 216, and the counter 215 is supplied to the clock supplied from the second control signal generator 218. Accordingly, when the counting value of the counter 215 and the data value of the address "0" input from the acceleration RAM 202 coincide with each other, the comparator 216 outputs one pulse. According to the pulse output from the comparator 216, the counting value of the counter 215 is reset to "0", and the values of the up / down counter 211 and the address counter 207 increase by "1".

At this time, the address counter 207 provides the address so that data of address "1" is input to the comparator 216, and the up / down counter 211 outputs the value stored in the pattern memory 219. This results in the step motor 117 moving one step.

Subsequently, when the counting value of the counter 215 and the data value of the address "1" input from the acceleration RAM 202 match, the comparator 216 outputs one pulse signal. The described operation is repeated. This operation is performed according to the control of the central processing unit 101 when the acceleration step number is determined according to the speed according to the set resolution, that is, the scanning operation is performed when the scanning command is received. 212 is set to acceleration "0" and constant speed "1", and the step motor 117 is switched to the constant speed state. At this time, the address of the acceleration RAM 202 is not changed, and the scanning operation of the image is performed after passing through the stabilization period by repeatedly performing a constant address for a certain step.

Thereafter, when the scanning operation is performed by the predetermined amount (step number), the step motor 117 is switched to the deceleration state. That is, when the register 212 is set to the constant speed "0" and the deceleration "1" under the control of the central processing unit 101, the deceleration ram 203 is enabled and the address of the deceleration ram 203 is "0". Becomes In this state, the deceleration data output at the address "0" of the deceleration ram 203 is input to the comparator 216, and the counter 215 has a counting value according to the clock provided from the second control signal generator 218. Incremented by "1".

The comparator 216 generates one pulse signal when the counting value of the counter 215 and the data value of "0" input from the deceleration RAM 203 match, and counts the address counter 207 according to the pulse. Decrease data of address "1" stored in deceleration ram 203 by increasing value by "1" to input to comparator 216, and counting value of up / down counter 211 is increased to form pattern memory 219. As the driving pattern of the step motor 117 corresponding to the next step is outputted, the step motor 117 advances by one step. When the deceleration process is completed after the operation is performed by the number of acceleration steps described above, the central processing unit 101 sets the register 212 to the deceleration " 0 " and the stop " 0 " states. 117 stops.

Thereafter, in the state where the register 212 sets the rotation direction of the step motor 117 to "1", if the above steps are repeated, the step motor 117 performs reverse rotation. As a result, by repeating the above process, it is possible to control the image scanning operation for the preset area.

Therefore, according to the first and second embodiments of the present invention, the drive pattern of the step motor 117 does not need to be stored for each resolution that can be designated by the user, and only the small acceleration / deceleration patterns are stored, corresponding to the respective resolutions. Thus, the driving state of the flatbed scanner can be easily controlled.

As described above, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the claims below and equivalents thereof.

As a result, according to the step motor control method and apparatus according to the present invention the following advantages occur.

First, by storing one acceleration / deceleration pattern and the final speed data corresponding to each resolution without having to store a plurality of acceleration / deceleration patterns for each resolution, the capacity of data to be stored in the storage medium is reduced, thereby storing. Since the capacity of the medium can be reduced, manufacturing cost can be reduced.

Second, the control operation is simplified by controlling the feed speed of the step motor using one acceleration / deceleration pattern and the final speed data corresponding to each resolution.

Third, in controlling the speed of the step motor, one acceleration / deceleration pattern and the final speed data corresponding to each resolution can be applied to all resolutions, so that distortion does not occur in the acquired image, thereby providing stable image information. Can be obtained.

Claims (8)

It includes a step motor that provides a driving force for scanning by moving the scanning module with respect to the original placed on the plate, and a storage medium for storing the acceleration and deceleration pattern and the final speed data for each resolution, at least two resolutions can be selected For flatbed scanners: Detecting the acceleration / deceleration pattern and the number of steps to which the acceleration / deceleration pattern is applied and the final speed data of the designated resolution corresponding to an arbitrary resolution designated by the user; Accelerating the step motor by applying the detected acceleration / deceleration speed data by the number of steps; And if the current step number exceeds the step number, driving the step motor using the designated final speed data. The method according to claim 1, wherein the acceleration / deceleration pattern is Step motor control method characterized in that the acceleration / deceleration pattern corresponding to the minimum resolution. It includes a step motor that provides a driving force for scanning by moving the scanning module with respect to the original placed on the plate, and a storage medium for storing the acceleration and deceleration pattern and the final speed data for each resolution, at least two resolutions can be selected For flatbed scanners: A RAM configured to store the acceleration / deceleration pattern and the final velocity data for each resolution stored in the storage medium; An address buffer configured to provide an address for storing the acceleration / deceleration pattern and the final speed data for each resolution in the RAM; A data buffer temporarily buffering the acceleration / deceleration pattern and the final speed data in the RAM; A register storing various information necessary for driving the step motor; An address counter which provides an address for detecting acceleration / deceleration pattern and final speed data corresponding to a resolution designated by a user from the RAM when the step motor is driven; A configurable counter which receives the acceleration / deceleration pattern and the final speed data corresponding to the resolution designated by the user from the RAM and down counts one step according to a clock provided from a clock generator; An interrupt generator for generating an interrupt signal whenever the counting value of the settable counter becomes "0"; And In response to the interrupt signal output from the interrupt generator as a clock, the counter value is applied to the counting value according to the rotation direction of the step motor specified in the register according to the acceleration / deceleration pattern specified by the user. And a up / down counter for controlling the rotational speed of the step motor. The method of claim 3, wherein the RAM, An acceleration RAM configured to store the acceleration pattern and the final speed data of the resolution among the acceleration / deceleration pattern and the final speed data of each resolution; And And a deceleration ram for storing the deceleration pattern among the acceleration / deceleration pattern and the final speed data for each resolution. The method of claim 3, wherein the acceleration / deceleration pattern is Step motor control method characterized in that the acceleration / deceleration pattern corresponding to the minimum resolution. It includes a step motor that provides a driving force for scanning by moving the scanning module with respect to the original placed on the plate, and a storage medium for storing the acceleration and deceleration pattern and the final speed data for each resolution, at least two resolutions can be selected For flatbed scanners: A RAM configured to store the acceleration / deceleration pattern and the final velocity data for each resolution stored in the storage medium; An address counter for storing or detecting the acceleration / deceleration pattern and the final speed data for each resolution in the RAM to control the step motor; A data buffer temporarily buffering the acceleration / deceleration pattern and the final speed data in the RAM; A counter for counting a clock provided from the clock generating means; Comparing the counting value of the counter and the data values of the acceleration / deceleration pattern and the final speed data designated by the user among the acceleration / deceleration pattern and the final speed data for each resolution stored in the RAM, and output a predetermined control signal according to the result. Comparator; A register storing various information necessary for driving the step motor; An up / down counter which generates an address while performing up counting and down counting operations according to the signal output from the comparator and the rotation direction information output from the register; And And a control signal generator for increasing and decreasing an address counting value provided to the RAM in the address counter according to an output signal of the comparator and an output signal of the register. The method of claim 6, wherein the ram, An acceleration RAM configured to store the acceleration pattern and the final speed data of the resolution among the acceleration / deceleration pattern and the final speed data of each resolution; And And a deceleration ram for storing the deceleration pattern among the acceleration / deceleration pattern and the final speed data for each resolution. The method of claim 6, wherein the acceleration and deceleration pattern, Step motor control method characterized in that the acceleration / deceleration pattern corresponding to the minimum resolution.