JP2005228632A - Key device and electronic equipment provided with this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a key device in which discrimination property of the key and user-friendliness of the person in charge are improved while power consumption is reduced, and also to provide an electronic equipment provided with this. <P>SOLUTION: A Clark key 10 is provided with a metal ring 102, while a key reader 11 is provided with a magnetic sensor 113 and a magnet ring 115. Since a change occurs in the distribution of magnetic field of the magnet ring 115 between the state in which the Clark key 10 is mounted on the key reader 11 and the state in which it is dismounted, this change is detected by the magnetic sensor 113 to find out the mounting state of the Clark key 10. Only when the Clark key 10 is mounted, electric waves for questioning are emitted via an antenna 111 provided at the key reader 11, and key data stored in a transponder 101 provided at the Clark key 10 is read by wireless communication. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention includes a key storing data and a key reader for reading the data stored in the key by wireless communication, and a key device for identifying the key based on the data read from the key, and an electronic device including the same Regarding equipment.

  A cash register such as a POS (Point of Sales) terminal or an ECR (Electronic Cash Register) has a clerk key device that is a key device for distinguishing a person in charge (clerk). The clerk key device includes a clerk key owned by a person in charge, a keyhole unit for inserting the clerk key, and an identification means for identifying the inserted clerk key. Further, a key device is used as a security device for authenticating a user in a PC (personal computer) server or the like.

  FIG. 10 is a configuration diagram of a conventional clerk key device 200. The portion of the clerk key 201 that is inserted into the keyhole unit 202 is provided with an unevenness 201a. By inserting the clerk key 201 into the keyhole unit 202, the contact 203 in the keyhole unit 202 is turned ON / OFF by the unevenness 201a. . The contact 203a that is turned on outputs “1”, and the contact 203b that is turned off outputs “0”. A signal indicating the state of each contact is output from the output I / F (interface) 204 to the identification unit 205. In the clerk key device 200, the number of concaves and convexes 201a and the number of contacts 203 are both 7, and the signal output from the output I / F 204 is a 7-bit signal. For example, if the contact on the back side of the keyhole unit 202 is the upper bit and the contact on the near side is the lower bit, “1101111” is output as key data in the state of FIG. The identification unit 205 stores a correspondence table between the person in charge and the key data. When a signal from the output I / F 204 is received, the person in charge corresponding to the key data is identified based on the correspondence table.

  As described above, in the conventional clerk key device, since the unevenness and the contact point need to contact each other, there is a problem that the contact portion is worn during use and cannot be correctly identified. Moreover, since the attachment position of the keyhole unit in the cash register is a limited position, the keyhole becomes small and it is difficult to insert the clerk key.

In order to solve these problems, the following techniques have been developed.
The key system described in Patent Document 1 includes a key, a cylinder, and a computer. An RFID (Radio Frequency Identification) module is built in the key insertion part, and the key is identified without contact by wireless communication between the antenna unit in the cylinder and the RFID module. By integrating the IC element with the antenna, the RFID module is miniaturized, and the key is miniaturized and the price is reduced.

  The locking device described in Patent Document 2 uses a light emitting element to output a calling code from a key device, and returns a random response code from the locking device that has received the calling code. A recognition code is output from the key device that has recognized the response code, and unlocked if the recognition code received by the locking device is correct.

  In addition, an immobilizer is used for a key device of an automobile. An immobilizer is a transponder (electronic chip) embedded in an ignition key, and communicates with an engine control circuit using a radio frequency link. The unique ID code of the transponder embedded in the key is collated electronically with the ID code of the vehicle-side controller. If the ID codes match, the ignition is started and the engine is started. If they do not match, it will not ignite and the engine will not start.

  Further, the IC built-in type key is magnetically attracted to a predetermined position on the main body side by a magnet, and the contact of the key and the contact on the main body side are contacted to perform identification.

  In the non-contact type key control device described in Patent Document 3, the detection operation of the infrared sensor 60 is an intermittent operation at intervals of 1 second. When a proximity object is detected five times consecutively by this detection operation, the intermittent operation is 1 Change to minute interval. When the proximity object is detected five times in succession, the interval of the intermittent operation is changed to be longer.

JP 2003-129714 A JP-A-5-141139 Japanese Patent Laid-Open No. 11-131879

  Since the key system described in Patent Document 1 is non-contact, wear does not pose a problem, but since the key needs to be inserted into the cylinder, there remains a problem with the difficulty of key insertion. The locking device described in Patent Document 2 cannot be used if there is an obstacle between the key device and the locking device, and the key device and the locking device cannot be fixed for a certain period of time like a clerk key.

  The immobilizer uses a transponder only for identification of the ID code, and there is no substitute for contacting the inside of the cylinder when rotating the ignition key. The IC built-in type key may not be identified because the contact becomes unstable when the contact portion is dirty.

  The non-contact type key control device described in Patent Document 3 performs a detection operation at intervals of 1 second when a proximity object is not detected. Certainly, if a proximity object is detected, the interval of intermittent operation will be longer, so it may be possible to reduce power consumption, but the proximity object is actually detected during the period of locking and unlocking the key. Since the period in which no proximity object is detected is much longer, the effect of reducing power consumption is slight.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a key device and an electronic device including the key device that improve the identification of a key and the convenience of a person in charge and reduce power consumption.

The present invention comprises a key incorporating a transponder storing data;
A key reader with a built-in interrogator for reading data stored in the transponder via wireless communication;
A key device having control means for identifying a key based on data read from a transponder by an interrogator,
The key reader has state detection means for detecting whether the state of the key is a first state attached to the key reader or a second state detached from the key reader;
The control means controls the interrogator so that the interrogator is operated to read data from the transponder when the key state is the first state, and is not operated when the key state is the second state. It is a key device.

  Further, the present invention is characterized in that the key and the key reader are detachable by magnetic force adsorption.

In the present invention, the key reader has a ring-shaped magnet,
The state detecting means detects which state is by detecting a change in the magnetic field between the first state and the second state with a magnetic sensor.

  In the present invention, the interrogator is arranged so that the pointing direction of the antenna included in the interrogator is substantially parallel to the central axis passing through the center of the ring-shaped magnet when the key and the key reader are fixedly attracted. It is characterized by that.

  In the present invention, the transponder is arranged so that the pointing direction of the antenna provided in the transponder is substantially parallel to the central axis passing through the center of the ring-shaped magnet when the key and the key reader are attracted and fixed. It is characterized by.

Further, the present invention is characterized in that the polarity of the ring-shaped magnet is magnetized in the thickness direction.
Moreover, this invention is an electronic device provided with said key apparatus, Comprising:
The control means is based on the data read by the interrogator from the transponder,
It is an electronic device characterized by determining whether or not at least the electronic device can be operated.

In the present invention, the data read from the transponder by the interrogator is the first data,
The control means can convert the first data into second data having a different format.

  According to the present invention, when the interrogator built in the key reader reads data from the transponder built in the key by wireless communication, the key is identified based on the data read by the control means. The key and the key reader are detachable, and communication between the interrogator and the transponder is performed more accurately when the key and the key reader are installed at predetermined positions.

  The state detection means provided in the key reader detects the attachment / detachment state of the key, and the control means controls the operation of the interrogator according to the detection result of the state detection means. The key state includes a first state in which the key is attached to the key reader and a second state in which the key is detached from the key reader, and the control means has an interrogator when the key state is in the first state. Is operated to read data from the transponder, and the interrogator is controlled not to operate the interrogator in the second state.

  As a result, the interrogator operates only when the key is attached to the key reader, that is, in the first state where the distance between the interrogator and the transponder is a communicable distance, thereby reducing power consumption. be able to.

  Conventionally, since a radio wave for reading data is transmitted from the interrogator with the key detached from the key reader, this transmitted radio wave causes malfunction of devices around the key device, so-called EMI (Electro Magnetic Interference). Failure is a problem. On the other hand, in the present invention, when radio waves are transmitted from the interrogator, the key is always attached and functions as a shield, and when the key is detached, no radio waves are transmitted, thus preventing generation of EMI due to the transmitted radio waves. can do.

Moreover, according to this invention, a key and a key reader can be attached or detached by magnetic adsorption.
The data communication between the key and the key reader uses a so-called RFID system using an interrogator and a transponder, so that occurrence of communication failure due to obstacles, contamination of contacts, etc. can be reduced. Further, since the key and the key reader can be fixed by magnetic force adsorption, it is not necessary to insert the key into the key hole, and the key can be easily brought into contact with a desired position and fixed. Therefore, it is possible to improve the usability of the person in charge and the identification of the key.

  According to the invention, the key reader has a ring-shaped magnet, and the state detection means detects the change in the magnetic field between the first state and the second state with the magnetic sensor. Detect if there is.

  Since the key and the key reader can be attached and detached by magnetic force adsorption, when the key reader has a magnet, the key has a metal (magnetic body) plate facing the magnet, or also a magnet. The magnetic field distribution by the magnet in the second state is greatly different from the magnetic field distribution in the first state. Since the key is provided with a metal plate or a magnet, the magnetic field lines are concentrated on the metal plate or magnet having a smaller magnetic resistance than in the air, and the distribution of the magnetic field changes. By providing the magnetic sensor at a position where the change in the magnetic field distribution can be detected, it is possible to easily detect the state change.

  Further, according to the present invention, when the key and the key reader are attracted and fixed, the interrogator is arranged so that the antenna directing direction of the interrogator is substantially parallel to the central axis passing through the center of the ring-shaped magnet. Place.

  Thereby, since the radio wave transmitted from the interrogator and the radio wave transmitted from the transponder pass near the center of the ring, wireless communication can be easily performed even if a magnet is interposed between the key and the key reader.

  According to the present invention, the transponder is arranged so that the pointing direction of the antenna provided in the transponder is substantially parallel to the central axis passing through the center of the ring-shaped magnet when the key and the key reader are attracted and fixed. To do.

  The key reader is generally fixed to the device, and the key is often carried by the user. Because of fixing by magnetic attraction, the key is not always fixed in the same state. By making the directivity direction of the antenna included in the transponder substantially parallel to the central axis passing through the center of the ring-shaped magnet, wireless communication can be reliably performed even if the key rotates about the central axis.

Further, according to the present invention, the ring-shaped magnet is magnetized in the thickness direction.
Thereby, since the distribution of the magnetic field spreads in the thickness direction of the magnet, the arrangement of the magnetic sensor is facilitated.

  According to the invention, there is provided an electronic apparatus including the key device described above, and the control means determines whether or not at least the electronic apparatus can be operated based on data read by the interrogator from the transponder.

  For example, data stored in the transponder in advance is registered in the electronic device, and if the data read by the interrogator is registered, the electronic device can be operated, and if not registered, it cannot be operated. Thereby, a security function can be improved.

  In addition, when the electronic device is an electronic cash register, it operates by switching a plurality of operation modes such as a registration mode, an inspection mode, and a payment mode. When the electronic device is a PC server, an administrator (administrator) mode, Operates in multiple modes such as user mode.

  Among these operation modes, selectable operation modes are determined for each user of the device. Therefore, the correspondence between the data stored in the transponder and the operable mode is registered in the electronic device in advance, and the operation mode that can be selected by the user having the key is selected according to the data read by the interrogator. It is also possible to decide.

  According to the present invention, the data read from the transponder by the interrogator is used as the first data, and the control means converts the first data into the second data having a different format.

  Since the data assigned to the transponder is a unique ID, the format is different from the key data for identifying the key used in the conventional electronic device. Therefore, if the data assigned to the transponder is the first data and the key data in the conventional format is the second data, the data assigned to the transponder can be converted from the data assigned to the transponder by the control means, improving versatility. To do.

  Hereinafter, an electronic cash register such as a POS terminal and an ECR will be described as an electronic device including a key device. In an electronic cash register, in order to operate the apparatus, it is necessary to identify whether or not a correct person uses it. A key device is used as means for identifying the person in charge.

First, the first embodiment will be described.
FIG. 1 is a block diagram showing an electrical configuration of an electronic cash register (hereinafter abbreviated as “ECR”) 100 according to a first embodiment of the present invention. The ECR 100 is realized by, for example, a microprocessor or the like, and is a central processing unit (hereinafter abbreviated as “CPU”) 1 that controls the overall operation of the ECR 100, and a read-only memory in which programs for controlling various operations of the ECR 100 are stored. (Hereinafter abbreviated as “ROM”) 2 and a random access memory (hereinafter abbreviated as “RAM”) 3 in which various setting contents are stored. In addition, a mode switch (SW) 4 used for switching the operation mode of the ECR 100, a keyboard 5 for inputting a product department code, a sales amount, and the like, and a calculation result of the CPU 1 are printed on a receipt and a recording sheet. A printer 6, a display device 7 realized by, for example, a liquid crystal display for displaying the sales amount, a drawer 8 for storing coins and bills, a buzzer 9 for notifying operation mistakes, and the like A clerk key 10 for identifying a person and a key reader 11 for identifying the clerk key 10 are included.

  FIG. 2 is a diagram illustrating a memory configuration of the RAM 3. As memories relating to transactions with customers, for example, there are a sales amount memory 3a in which the sales amount of merchandise is set and a remaining amount memory 3b in which the remaining amount is set.

  In addition, there is a person-in-charge code memory 3c that records which clerk key is valid. The person-in-charge code memory 3c stores person-in-charge codes and key data of clerk keys corresponding to them. If a clerk key matching this code is not attached to the key reader, the operation mode of the ECR 100 is limited. For example, the ECR 100 cannot be operated even when the mode SW4 is in the “register” position. The CPU 1, ROM 2, and RAM 3 constitute a control means.

  FIG. 3 is a perspective view showing the external appearance of the ECR 100. A display device 7 is arranged at the upper right of the upper surface of the ECR 100, and a printer 6 is arranged beside the display device 7. The keyboard 5 is arranged in the lower half of the upper surface. The key reader 11 is disposed on the right side of the front surface, and FIG. 3 shows a state in which the clerk key 10 is fixed to the key reader 11.

  FIG. 4 is a diagram illustrating an arrangement of each component of the key reader 11. FIG. 5 is a cross-sectional view of the clerk key 10 and the key reader 11. Note that FIG. 4 is a transparent diagram, and the configuration of the key reader 11 cannot actually be seen from the outside of the ECR 100.

  The clerk key 10 incorporates a transponder 101, and a metal ring 102, which is a metal plate for fixing to the key reader 11 by magnetic force adsorption, is attached. The key reader 11 includes an antenna 111, a reader substrate 112, and a magnetic sensor 113 for communicating with the transponder 101 of the clerk key 10. The antenna 111 and the leader board 112 constitute an interrogator. The key reader 11 is provided with a magnet ring 115 for fixing the clerk key 10 by magnetic attraction, and the inner diameter of the magnet ring 115 is larger than the outer diameter of the metal ring 102 provided in the clerk key 10. ing. Accordingly, the clerk key 10 is mounted so as to fit inside the key reader 11. As shown in FIG. 5, the magnet ring 115 and the metal ring 102 are magnetically attracted via the outer wall of the ECR 100. Wireless communication between the transponder 101 and the antenna 111 is also performed through the outer wall. When the clerk key 10 is attached to the key reader 11, the metal ring 102 is in the inner periphery of the magnet ring 115. Wireless communication between the transponder 101 and the antenna 111 is performed in a state where the clerk key 10 is attached to the key reader 11.

  FIG. 6 is a schematic diagram showing changes in the magnetic field distribution depending on the wearing state of the clerk key 10. FIG. 6A shows the magnetic field distribution in the first state, and FIG. 6B shows the magnetic field distribution in the second state. Here, the first state is a state where the clerk key 10 is attached to the key reader 11, and the second state is a state where the clerk key 10 is detached from the key reader 11. The magnetic sensor 113 is disposed at a position where a change in the magnetic field distribution can be detected in the first state and the second state. If the magnet ring 115 is magnetized in the thickness direction, the distribution of the magnetic field spreads in the thickness direction of the magnet ring 115, so that the range in which the change can be detected is large and the magnetic sensor 113 can be easily arranged. become. For example, when arranged within the inner periphery of the magnet ring 115, the magnetic field lines penetrate the magnetic sensor 113 in the second state, but in the first state, the magnetic field lines concentrate on the metal ring 102 that is a magnetic body. The lines of magnetic force penetrating the magnetic sensor 113 are reduced. The magnetic sensor 113 detects the number of lines of magnetic force, that is, the level of magnetic flux density.

  The magnetic sensor 113 outputs a change in state between the first state in which the clerk key 10 is attached to the key reader 11 and the second state in which the clerk key 10 is detached from the key reader 11 to the leader substrate 112 as a detection result. The leader substrate 112 outputs the detection result input from the magnetic sensor 113 to the CPU 1. The CPU 1 determines the current state of the clerk key 10 based on the detection result of the magnetic sensor 113 input from the leader board 112.

  If the state of the clerk key 10 is the first state, the CPU 1 outputs a data reading instruction to the antenna 111 to the reader substrate 112. The reader board 112 causes the antenna 111 to transmit a question radio wave based on the data reading instruction input from the CPU 1.

  In the first state where the clerk key 10 is attached to the key reader 11, the transponder 101 receives the interrogation radio wave, converts the power, and transmits the key data stored in advance in the built-in memory to the key reader 11. To do. The leader board 112 transmits the received key data to the CPU 1. The CPU 1 can identify the fixed clerk key 10 by comparing the received key data with the person-in-charge code.

  If the clerk key 10 is in the second state, the CPU 1 does not output any data reading instruction so as not to operate the antenna 111.

  Thus, the antenna 111 operates only when the clerk key 10 is attached to the key reader 11, that is, in the first state where the distance between the antenna 111 and the transponder 101 is a communicable distance. Power consumption can be reduced.

  Conventionally, even when the clerk key 10 is detached from the key reader 11, a radio wave for reading data is transmitted from the antenna 111. Therefore, the EMI failure that causes malfunction of devices around the key device is a problem. Become. In the present invention, when radio waves are transmitted from the antenna 111, the clerk key 10 is always attached and functions as a shield, and when the clerk key 10 is detached, no radio waves are transmitted. Occurrence can be prevented.

  FIG. 7 is a flowchart showing the clerk key recognition process. This process is performed when the key is mounted while the power of the ECR 100 is on. First, in step S1, the magnetic sensor 113 determines whether or not the clerk key 10 is attached. If the clerk key 10 is not attached, the process waits, and if it is attached, the process proceeds to step S2. In step S2, the key reader 11 reads the key data stored in the transponder of the clerk key 10 by wireless communication. In step S3, key data is output from the key reader 11 to the CPU 1. In step S4, the CPU 1 performs a comparison with the person-in-charge code based on the input key data, and recognizes the clerk key 10. In step S5, the magnetic sensor 113 determines whether or not the clerk key 10 is attached. If the clerk key 10 is attached, the process waits. If not, the CPU 1 is notified that the clerk key 10 has been detached in step S6, and the process is terminated.

  In the above description, the clerk key 10, particularly the metal ring 102 is configured to be mounted inside the magnet ring 115 of the key reader 11. However, the inner diameter of the metal ring 102 is larger than the outer diameter of the magnet ring 115. It may be a configuration.

  FIG. 8 is a schematic diagram showing changes in the magnetic field distribution depending on the wearing state of the clerk key 10 according to another embodiment. FIG. 8A shows the magnetic field distribution in the first state, and FIG. 8B shows the magnetic field distribution in the second state. The magnetic sensor 113 is disposed at a position where a change in the magnetic field distribution can be detected in the first state and the second state. For example, when arranged outside the outer periphery of the metal ring 102, the magnetic field lines penetrate the magnetic sensor 113 in the second state, but in the first state, the magnetic field lines concentrate on the metal ring 102 that is a magnetic body. The lines of magnetic force penetrating the magnetic sensor 113 are reduced. The magnetic sensor 113 detects the level of magnetic flux density.

  The magnetic sensor 113 outputs a change in state between the first state in which the clerk key 10 is attached to the key reader 11 and the second state in which the clerk key 10 is detached from the key reader 11 to the leader substrate 112 as a detection result. The leader substrate 112 outputs the detection result input from the magnetic sensor 113 to the CPU 1. The CPU 1 determines the current state of the clerk key 10 based on the detection result of the magnetic sensor 113 input from the leader board 112.

  Moreover, although the case where the annular magnet ring 115 was used was demonstrated above, the magnet ring 116 which consists of a part of annular | circular shape may be sufficient as shown, for example in FIG. FIG. 9 is a diagram showing the shape of the magnet ring 116. FIG. 9A is a front view, and FIG. 9B is a top view. As shown in the figure, the shape of the magnet ring is such that when the clerk key 10 is attached to the key reader 11, it does not interfere with wireless communication between the transponder 101 of the clerk key 10 and the antenna 111 of the key reader 11. That is, it is sufficient that no magnet exists on a straight line connecting the transponder 101 and the antenna 111. When the magnet ring is formed of a part of an annular ring, each magnet piece may be arranged at a predetermined position on the outer wall of the ECR 100.

As in the prior art, when the interrogation radio wave is continuously transmitted using the proximity RFID having a wireless communication distance of about 1 to 2 mm, the current consumption is about several tens to 100 mA. In contrast, since the current consumption of the magnetic sensor is 10 mA or less, the key device using the magnetic sensor can be used not only in a battery-driven device but also in a standby state of a device using a commercial power supply. For example, in a device in a standby state, the average current consumption when the magnetic sensor is operated at regular intervals and the key is attached to the key reader to return from the standby state is as follows.
Operating conditions: operating interval = 500 msec, operating time = 1 msec, current consumption = 10 mA
Average current consumption = (operation time / operation interval) × current consumption = (1 msec / 500 msec)
× 10mA = 0.02mA

  As described above, the average current consumption can be significantly reduced as compared with the conventional case, so that security can be ensured by the key device in the standby state, and the return from the standby state can be speeded up.

  Since the present invention can prevent the occurrence of EMI as described above, it can be used to ensure the security of medical devices used mainly in hospitals, for example. In addition, there is little influence on wireless communication such as a wireless local area network (LAN) in the vicinity, and the number of retries due to a communication error can be reduced.

1 is a block diagram showing an electrical configuration of an electronic cash register (ECR) 100 according to a first embodiment of the present invention. 2 is a diagram illustrating a memory configuration of a RAM 3. FIG. It is a perspective view which shows the external appearance of ECR100. It is a figure which shows arrangement | positioning of each structure of the key reader. It is sectional drawing of the clerk key 10 and the key reader 11. It is a schematic diagram which shows the change of magnetic field distribution by the wearing state of the clerk key. It is a flowchart which shows a clerk key recognition process. It is a schematic diagram which shows the change of magnetic field distribution by the mounting state of the clerk key 10 in other embodiment. It is a figure which shows the shape of the magnet ring. It is a block diagram of the conventional clerk key apparatus.

Explanation of symbols

1 Central processing unit (CPU)
2 Read-only memory (ROM)
3 Random access memory (RAM)
4 Mode switch (SW)
5 Keyboard 6 Printer 7 Display 8 Drawer 9 Buzzer 10 Clarke Key 11 Key Reader 100 Electronic Cash Register (ECR)
101 Transponder 102 Metal ring 111 Antenna 112 Leader board 113 Magnetic sensor 115 Magnet ring

Claims (8)

A key with a built-in transponder that stores data,
A key reader with a built-in interrogator for reading data stored in the transponder via wireless communication;
A key device having control means for identifying a key based on data read from a transponder by an interrogator,
The key reader has state detection means for detecting whether the state of the key is a first state attached to the key reader or a second state detached from the key reader;
The control means controls the interrogator so that the interrogator is operated to read data from the transponder when the key state is the first state, and is not operated when the key state is the second state. Key device to play.   The key device according to claim 1, wherein the key and the key reader are detachable by magnetic force adsorption. The key reader has a ring-shaped magnet,
3. The key device according to claim 2, wherein the state detection means detects which state is by detecting a change in the magnetic field between the first state and the second state by a magnetic sensor.   The interrogator is arranged so that the pointing direction of the antenna provided in the interrogator is substantially parallel to the central axis passing through the center of the ring-shaped magnet when the key and key reader are attracted and fixed. The key device according to claim 3.   The transponder is arranged such that when the key and the key reader are attracted and fixed, the antenna directing direction of the transponder is substantially parallel to the central axis passing through the center of the ring-shaped magnet. Item 4. The key device according to item 3.   6. The key device according to claim 4, wherein the ring-shaped magnet is magnetized in the thickness direction. An electronic device comprising the key device according to any one of claims 1 to 6,
The control means is based on the data read by the interrogator from the transponder,
An electronic device characterized by determining whether or not at least an electronic device can be operated. The data read from the transponder by the interrogator is the first data,
8. The electronic apparatus according to claim 7, wherein the control means is capable of converting the first data into second data having a different format.

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