Non-contact communication medium, magnetic tape cartridge, non-contact communication system, method for operating non-contact communication medium, and program

Abstract

To provide a non-contact communication medium, a magnetic tape cartridge, a non-contact communication system, an operating method for the non-contact communication medium, and a program that can stabilize the supply of operating power to a processing circuit while enabling an external device to accurately read the contents of a response signal.SOLUTION: A non-contact communication medium communicates with an external device in a non-contact manner. The non-contact communication medium includes a resonant circuit, a regulator that generates operating power, a variable resistor, a switch, and a control circuit. The processing circuit generates a response signal in response to a command signal. The switch switches between a load-applying state in which a load of the variable resistor is applied to the resonant circuit and a non-loading state in which no load is applied to the resonant circuit in response to the response signal. The control circuit controls the resistance value in response to the escape power released from the regulator.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present disclosure relates to a non-contact communication medium, a magnetic tape cartridge, a non-contact communication system, a method of operating the non-contact communication medium, and a program. [Background technology]

[0002] Patent Document 1 discloses a technique for recording information related to data recorded on a magnetic tape included in a magnetic recording tape cartridge, in a contactless memory IC tag included in the magnetic recording tape cartridge.

[0003] Patent Document 2 discloses a radio frequency interface circuit for a radio frequency identification tag. The radio frequency interface circuit described in Patent Document 2 includes at least one pair of input terminals for connecting the interface circuit to an antenna means of the radio frequency identification tag, one or more variable resistance loads coupled to the input terminal pair, one or more rectifiers having input sides connected to the input terminal pair and output sides connected to the parallel connection of a voltage control means and a modulation control means, and a combining means for receiving output signals from the voltage control means and the modulation control means. The combining means is configured to generate a control signal for controlling each variable resistance load in response to a received signal so that each variable resistance load operates as a modulation and voltage adjustment circuit, and each variable resistance load is configured to act as an electrostatic discharge protection circuit.

[0004] In addition, in the radio frequency interface circuit described in Patent Document 2, the combining means detects an overvoltage state from the output signal received from the voltage control means, generates a control signal for setting each variable resistance load to a value that limits the input voltage of each rectifier, and modulates the control signal according to the output signal received from the modulation control means to modulate the resistance value of each variable resistance load in order to transmit data through the antenna means of the radio frequency identification tag. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2006-323918 A [Patent Document 2] Special Publication No. 2009-519699 Summary of the Invention

[0006] One embodiment of the present disclosure provides a non-contact communication medium, a magnetic tape cartridge, a non-contact communication system, an operating method of the non-contact communication medium, and a program that can stabilize the supply of operating power to a processing circuit and enable an external device to accurately read the contents of a response signal. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a non-contact communication medium that communicates with an external device in a non-contact manner via a magnetic field applied from the external device, and includes a resonant circuit that generates an AC voltage by resonating using an induced current induced by the antenna coil when a magnetic field acts on the antenna coil, a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage, a variable resistor connected to the resonant circuit, a switch, and a control circuit, wherein the processing circuit generates a response signal in response to a command signal applied from the external device via the magnetic field, the switch switches between a load state in which the variable resistor is applied to the resonant circuit and a non-load state in which no load is applied to the resonant circuit in response to the response signal, and the control circuit controls the resistance value of the variable resistor in response to the escape power released from the regulator to generate operating power.

[0008] A second aspect of the present disclosure is a non-contact communication medium according to the first aspect, in which a processing circuit executes processing in response to a command signal and outputs a signal indicating a result obtained by executing the processing as a response signal.

[0009] A third aspect of the present disclosure is a non-contact communication medium according to the first or second aspect, in which the variable resistor is a pair of variable resistance elements connected to a resonant circuit, the switch corresponds to the pair of variable resistance elements and is a pair of switches capable of connecting the pair of variable resistance elements to a ground potential, and the applied state is realized when the pair of switches are turned on, and the non-applied state is realized when the pair of switches are turned off.

[0010] A fourth aspect of the present disclosure is a non-contact communication medium according to any one of the first to third aspects, in which the control circuit decreases the resistance value in accordance with the increase in the run-off power when the run-off power increases, and increases the resistance value in accordance with the decrease in the run-off power when the run-off power decreases.

[0011] A fifth aspect of the present disclosure is a contactless communication medium according to any one of the first to fourth aspects, comprising a memory to which information is written by a processing circuit and / or to which information is read by a processing circuit.

[0012] A sixth aspect of the present disclosure is a non-contact communication medium according to any one of the first to fifth aspects, in which the non-contact communication medium is mounted on a magnetic tape cartridge.

[0013] A seventh aspect of the present disclosure is a magnetic tape cartridge including a non-contact communication medium according to any one of the first to sixth aspects.

[0014] An eighth aspect of the present disclosure is a non-contact communication system including the non-contact communication medium according to any one of the first to sixth aspects and an external device.

[0015] A ninth aspect of the present disclosure is a method for operating a non-contact communication medium that communicates with an external device in a non-contact manner via a magnetic field applied from the external device, the method including: a resonant circuit that generates an AC voltage by resonating using an induced current induced by an antenna coil when a magnetic field acts on the antenna coil; a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage; a variable resistor connected to the resonant circuit; a switch; and a control circuit, the method including: the processing circuit generating a response signal in response to a command signal applied from the external device via the magnetic field; the switch switching between a load state in which a variable resistor is applied to the resonant circuit and a non-load state in which no load is applied to the resonant circuit in response to the response signal; and the control circuit controlling the resistance value of the variable resistor in response to the escape power released from the regulator to generate operating power.

[0016] A tenth aspect of the present disclosure is a program for causing a computer provided in a non-contact communication medium that communicates with an external device in a non-contact manner via a magnetic field provided from the external device to execute a modulation process, the program including: a resonant circuit that generates an AC voltage by resonating using an induced current induced by an antenna coil when a magnetic field acts on the antenna coil; a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage; a variable resistor connected to the resonant circuit; and a switch; the processing circuit generates a response signal in response to a command signal provided from the external device via the magnetic field; the switch switches between a load state in which the variable resistor is applied to the resonant circuit and a non-load state in which no load is applied to the resonant circuit in response to the response signal; and the modulation process includes a process of controlling the resistance value of the variable resistor in response to the escape power released from the regulator to generate operating power. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a conceptual diagram showing an example of a configuration of a magnetic tape system. [Diagram 2] 1 is a schematic perspective view showing an example of the appearance of a magnetic tape cartridge. [Diagram 3] FIG. 1 is a schematic diagram illustrating an example of a hardware configuration of a magnetic tape drive. [Figure 4] 1 is a schematic perspective view showing an example of a state in which a magnetic field is emitted from the bottom side of a magnetic tape cartridge by a reader / writer. FIG. [Diagram 5] FIG. 2 is a conceptual diagram showing an example of a hardware configuration of an electrical system of a cartridge memory mounted on a magnetic tape cartridge. [Figure 6] 4A and 4B are conceptual diagrams showing an example of the configuration of various circuits included in a cartridge memory, and example waveforms of a command signal and a response signal. [Figure 7] 1 is a conceptual diagram showing an example of a response signal being a coded signal with different modulation depths; FIG. [Figure 8] 6 is a conceptual diagram showing an example of a detailed hardware configuration of an electrical system of the cartridge memory shown in FIG. 5. [Figure 9] 10 is a flowchart showing an example of the flow of a modulation process executed by the cartridge memory. [Figure 10] FIG. 13 is a conceptual diagram showing a modified example of the detailed hardware configuration of the electrical system of the cartridge memory. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, examples of embodiments of a non-contact communication medium, a magnetic tape cartridge, a non-contact communication system, an operating method of a non-contact communication medium, and a program according to the present disclosure will be described with reference to the attached drawings.

[0019] First, the terms used in the following description will be explained.

[0020] CPU is an abbreviation for "Central Processing Unit". RAM is an abbreviation for "Random Access Memory". DRAM is an abbreviation for "Dynamic Random Access Memory". NVM is an abbreviation for "Non-Volatile Memory". EEPROM is an abbreviation for "Electrically Erasable and Programmable Read Only Memory". SSD is an abbreviation for "Solid State Drive". HDD is an abbreviation for "Hard Disk Drive". ASIC is an abbreviation for "Application Specific Integrated Circuit". PLD is an abbreviation for "Programmable Logic Device". FPGA is an abbreviation for "Field-Programmable Gate Array". IC is an abbreviation for "Integrated Circuit". RFID is an abbreviation for "Radio Frequency Identifier". UI is an abbreviation for "User Interface".

[0021] 1, as an example, a magnetic tape system 10 includes a magnetic tape cartridge 12 and a magnetic tape drive 14. The magnetic tape cartridge 12 is loaded into the magnetic tape drive 14. The magnetic tape cartridge 12 contains a magnetic tape MT. The magnetic tape drive 14 pulls out the magnetic tape MT from the loaded magnetic tape cartridge 12, and while running the pulled-out magnetic tape MT, records data on the magnetic tape MT and reads data from the magnetic tape MT.

[0022] In this embodiment, the magnetic tape cartridge 12 is an example of a "magnetic tape cartridge" according to the present disclosure, and the magnetic tape system 10 is an example of a "non-contact communication system" according to the present disclosure.

[0023] Next, an example of the configuration of the magnetic tape cartridge 12 will be described with reference to Figures 2 to 4. In the following description, for convenience of explanation, the loading direction of the magnetic tape cartridge 12 into the magnetic tape drive 14 is indicated by arrow A in Figures 2 to 4, the direction of arrow A is the front direction of the magnetic tape cartridge 12, and the front side of the magnetic tape cartridge 12 is the front side of the magnetic tape cartridge 12. In the following description of the structure, "front" refers to the front side of the magnetic tape cartridge 12.

[0024] 2 to 4, for convenience of explanation, the direction of arrow B perpendicular to the direction of arrow A is defined as the right direction, and the right side of the magnetic tape cartridge 12 is defined as the right side of the magnetic tape cartridge 12. In the explanation of the structure shown below, "right" refers to the right side of the magnetic tape cartridge 12.

[0025] 2 to 4, for convenience of explanation, the direction opposite to the direction of arrow B is referred to as the left direction, and the left side of the magnetic tape cartridge 12 is referred to as the left side of the magnetic tape cartridge 12. In the explanation of the structure shown below, "left" refers to the left side of the magnetic tape cartridge 12.

[0026] 2 to 4, for convenience of explanation, the direction perpendicular to the directions of arrows A and B is indicated by arrow C, the direction of arrow C is the upward direction of the magnetic tape cartridge 12, and the upward side of the magnetic tape cartridge 12 is the upper side of the magnetic tape cartridge 12. In the explanation of the structure given below, "upper" refers to the upper side of the magnetic tape cartridge 12.

[0027] 2 to 4, for convenience of explanation, the direction opposite to the front direction of the magnetic tape cartridge 12 is referred to as the rear direction of the magnetic tape cartridge 12, and the rear direction of the magnetic tape cartridge 12 is referred to as the rear side of the magnetic tape cartridge 12. In the explanation of the structure shown below, "rear" refers to the rear side of the magnetic tape cartridge 12.

[0028] 2 to 4, for convenience of explanation, the direction opposite to the upper direction of the magnetic tape cartridge 12 is referred to as the lower direction of the magnetic tape cartridge 12, and the lower side of the magnetic tape cartridge 12 is referred to as the lower side of the magnetic tape cartridge 12. In the explanation of the structure shown below, "lower" refers to the lower side of the magnetic tape cartridge 12.

[0029] 2, the magnetic tape cartridge 12 is generally rectangular in plan view and includes a box-shaped case 16. The case 16 contains the magnetic tape MT.

[0030] A supply reel 22 is rotatably housed inside the case 16. A magnetic tape MT is wound around the supply reel 22. An opening 16A1 is formed in the front side of the right wall 16A of the case 16. The magnetic tape MT is pulled out from the opening 16A1.

[0031] The case 16 contains a cartridge memory 24 as a storage medium other than the magnetic tape MT. An IC chip having an NVM is mounted on the cartridge memory 24. In this embodiment, a so-called passive RFID tag is used as the cartridge memory 24, and various information is read and written to the cartridge memory 24 (i.e., various information is acquired and stored) in a non-contact manner.

[0032] The cartridge memory 24 stores management information 15 for managing the magnetic tape cartridge 12. For example, the management information 15 includes information related to the cartridge memory 24, information related to the magnetic tape MT, and information related to the magnetic tape drive 14. In this embodiment, the cartridge memory 24 is an example of a "non-contact communication medium" according to the present disclosure, and the management information 15 is an example of "information" according to the present disclosure.

[0033] 3, the magnetic tape drive 14 includes a controller 25, a transport device 26, a magnetic head 28, and a UI device 29. The controller 25 includes a processing device 30 and a storage 32.

[0034] The magnetic tape cartridge 12 is loaded into the magnetic tape drive 14 in the direction of arrow A. In the magnetic tape drive 14, the magnetic tape MT is pulled out from the magnetic tape cartridge 12 and used. The magnetic tape drive 14 controls the magnetic tape cartridge 12 and each part within the magnetic tape drive 14 using management information 15 stored in a cartridge memory 24 and the like.

[0035] The magnetic tape drive 14 performs magnetic processing on the surface 31 of the magnetic tape MT using the magnetic head 28 while the magnetic tape MT is running. The surface 31 is a recording surface on which data is recorded. The magnetic processing refers to a recording process in which the magnetic head 28 records data on the surface 31 of the magnetic tape MT, and a reproducing process in which the magnetic head 28 reproduces data from the surface 31 of the magnetic tape MT. The magnetic tape drive 14 selectively performs a recording process and a reproducing process using the magnetic head 28. That is, the magnetic tape drive 14 pulls out the magnetic tape MT from the magnetic tape cartridge 12, and uses the magnetic head 28 to record data on the surface 31 of the pulled out magnetic tape MT, or uses the magnetic head 28 to reproduce data from the surface 31 of the pulled out magnetic tape MT.

[0036] The processing device 30 controls the entire magnetic tape drive 14. In this embodiment, the processing device 30 is realized by an ASIC. However, the present disclosure is not limited to this. For example, the processing device 30 may be realized by an FPGA and / or a PLD. The processing device 30 may also be realized by a computer including a CPU, a flash memory (e.g., an EEPROM and / or an SSD, etc.), and a RAM. The processing device 30 may also be realized by combining two or more of an ASIC, an FPGA, a PLD, and a computer (i.e., a computer having a processor that executes a program). That is, the processing device 30 may be realized by a combination of a hardware configuration and a software configuration.

[0037] The storage 32 is connected to the processing device 30, and the processing device 30 writes various information to the storage 32 and reads various information from the storage 32. An example of the storage 32 is a flash memory and / or a HDD. The flash memory and the HDD are merely examples, and any non-volatile memory that can be mounted in the magnetic tape drive 14 may be used.

[0038] The UI-based device 29 is a device having a reception function of receiving an instruction signal indicating an instruction from a user, and a presentation function of presenting information to the user. The reception function is realized by, for example, a touch panel, a hard key (e.g., a keyboard), and / or a mouse. The presentation function is realized by, for example, a display, a printer, and / or a speaker. The UI-based device 29 is connected to the processing device 30. The processing device 30 acquires the instruction signal received by the UI-based device 29. The UI-based device 29 presents various information to the user under the control of the processing device 30.

[0039] The transport device 26 is a device that selectively transports the magnetic tape MT in the forward or reverse direction along a predetermined path, and includes a feed motor 36, a take-up reel 38, a take-up motor 40, and multiple guide rollers GR. Note that the forward direction here refers to the feed direction of the magnetic tape MT, and the reverse direction refers to the rewind direction of the magnetic tape MT.

[0040] The supply motor 36 rotates the supply reel 22 in the magnetic tape cartridge 12 under the control of the processing device 30. The processing device 30 controls the supply motor 36 to control the rotation direction, rotation speed, rotation torque, etc. of the supply reel 22.

[0041] The take-up motor 40 rotates the take-up reel 38 under the control of the processing device 30. The processing device 30 controls the take-up motor 40 to control the rotation direction, rotation speed, rotation torque, and the like of the take-up reel 38.

[0042] When the magnetic tape MT is wound by the take-up reel 38, the processing device 30 rotates the supply motor 36 and the take-up motor 40 so that the magnetic tape MT runs in the forward direction along a predetermined path. The rotation speed, rotation torque, etc. of the supply motor 36 and the take-up motor 40 are adjusted according to the speed at which the magnetic tape MT is wound around the take-up reel 38. Furthermore, tension is applied to the magnetic tape MT by adjusting the rotation speed, rotation torque, etc. of the supply motor 36 and the take-up motor 40 by the processing device 30. Furthermore, the tension applied to the magnetic tape MT is controlled by adjusting the rotation speed, rotation torque, etc. of the supply motor 36 and the take-up motor 40 by the processing device 30.

[0043] When the magnetic tape MT is to be rewound onto the supply reel 22, the processing device 30 rotates the supply motor 36 and the take-up motor 40 so that the magnetic tape MT travels in the reverse direction along the predetermined path.

[0044] Each of the guide rollers GR guides the magnetic tape MT. The predetermined path, i.e., the running path of the magnetic tape MT, is determined by disposing the guide rollers GR at separate positions across the magnetic head 28 between the magnetic tape cartridge 12 and the take-up reel 38.

[0045] The magnetic head 28 includes a magnetic element unit 42 and a holder 44. The magnetic element unit 42 is held by the holder 44 so as to come into contact with the running magnetic tape MT. The magnetic element unit 42 has a plurality of magnetic elements.

[0046] The magnetic element unit 42 records data on the magnetic tape MT transported by the transport device 26, and reproduces data from the magnetic tape MT transported by the transport device 26.

[0047] The magnetic tape drive 14 includes a reader / writer 46. The reader / writer 46 is disposed below the magnetic tape cartridge 12 when the magnetic tape cartridge 12 is loaded so as to directly face the rear surface of the cartridge memory 24, and communicates with the cartridge memory 24 in a non-contact manner (e.g., reading and writing information from and to the cartridge memory 24). In this embodiment, the reader / writer 46 is an example of an "external device" according to the present disclosure.

[0048] As an example, as shown in FIG. 4, the reader / writer 46 is connected to the processing device 30. The processing device 30 outputs a command signal 48 to the reader / writer 46. The command signal 48 is a signal indicating a command to the cartridge memory 24. The reader / writer 46 generates a magnetic field MF in accordance with the command signal 48 input from the processing device 30, and emits the magnetic field MF from the lower side of the magnetic tape cartridge 12 toward the cartridge memory 24. The magnetic field MF emitted from the reader / writer 46 penetrates the cartridge memory 24. In this embodiment, the command signal 48 is an example of a "command signal" according to the present disclosure, and the magnetic field MF is an example of a "magnetic field" according to the present disclosure.

[0049] The reader / writer 46, under the control of the processing device 30, transmits a command signal 48 through space to the cartridge memory 24. When a command signal is transmitted through space from the reader / writer 46 to the cartridge memory 24, the command signal 48 is included in the magnetic field MF by the reader / writer 46 in accordance with an instruction from the processing device 30. In other words, the command signal 48 is superimposed on the magnetic field MF. That is, the reader / writer 46, under the control of the processing device 30, transmits the command signal 48 to the cartridge memory 24 via the magnetic field MF.

[0050] The reader / writer 46 communicates with the cartridge memory 24 in a non-contact manner via the magnetic field MF, thereby causing the cartridge memory 24 to perform a process in accordance with the command signal 48. For example, the reader / writer 46 transmits the command signal 48 to the cartridge memory 24, thereby causing the cartridge memory 24 to perform a process including a write process and / or a read process. The write process refers to, for example, a process of writing information determined in accordance with the command signal 48 from the management information 15 (see FIG. 2) into a storage area in the cartridge memory 24. The read process refers to, for example, a process of reading information determined in accordance with the command signal 48 from the management information 15 stored in the storage area in the cartridge memory 24, from the storage area.

[0051] The processing device 30 communicates with the cartridge memory 24 in a non-contact manner via the reader / writer 46 to write the management information 15 to the cartridge memory 24 and read the management information 15 from the cartridge memory 24 .

[0052] As an example, as shown in FIG. 5, the cartridge memory 24 includes a power generator 50, a demodulation circuit 52, a modulation circuit 53, and a computer 54. The power generator 50 includes a resonant circuit 50A, a rectifier circuit 50B, and a regulator 50C. The resonant circuit 50A includes an antenna coil 50A1 and a variable capacitor 50A2. The variable capacitor 50A2 is connected in parallel to the antenna coil 50A1. In the example shown in FIG. 5, a single variable capacitor 50A2 is connected in parallel to the antenna coil 50A1. In addition, the antenna coil 50A1 and the variable capacitor 50A2 are connected in parallel to the demodulation circuit 52 and are also connected in parallel to the rectifier circuit 50B.

[0053] In the present embodiment, the resonant circuit 50A is an example of a "resonant circuit" according to the present disclosure, and the antenna coil 50A1 is an example of an "antenna coil" according to the present disclosure.

[0054] The power generator 50 generates power 60 by the action of the magnetic field MF applied from the reader / writer 46 (see FIGS. 3 and 4) on the antenna coil 50A1. The power 60 is operating power for operating various circuits (e.g., the computer 54 and the demodulation circuit 52, etc.) in the cartridge memory 24. The power 60 is an example of "operating power" according to the present disclosure.

[0055] To generate power 60, the resonant circuit 50A resonates (i.e., generates a resonance phenomenon) using an induced current induced by the antenna coil 50A1 when the magnetic field MF acts on the antenna coil 50A1, thereby generating an AC voltage 56. The resonant circuit 50A outputs the AC voltage 56 to the rectifier circuit 50B.

[0056] The rectifier circuit 50B rectifies the AC voltage 56 input from the resonant circuit 50A to generate a DC voltage 58. The rectifier circuit 50B is connected to the regulator 50C and outputs the DC voltage 58 to the regulator 50C.

[0057] The regulator 50C is connected to various circuits included in the cartridge memory 24 (in the example shown in FIG. 5, the demodulation circuit 52, the computer 54, etc.). The regulator 50C generates power 60 (for example, DC power obtained by regulating the DC voltage 58 to a predetermined voltage value) based on the DC voltage 58 input from the rectifier circuit 50B, and supplies the power 60 to the various circuits included in the cartridge memory 24, thereby operating the various circuits included in the cartridge memory 24. In this embodiment, the regulator 50C is an example of a "regulator" according to the present disclosure.

[0058] The demodulation circuit 52 is connected to the resonant circuit 50 A. The demodulation circuit 52 extracts and demodulates the command signal 48 from the magnetic field MF received by the antenna coil 50 A 1, and outputs the demodulated command signal 48 to the computer 54 .

[0059] The computer 54 generates a response signal 61 in response to the command signal 48 input from the demodulation circuit 52 and outputs it to the modulation circuit 53. That is, the computer 54 executes processing according to the command signal 48 input from the demodulation circuit 52, and outputs a response signal 61 indicating the processing result to the modulation circuit 53. The modulation circuit 53 modulates the response signal 61 input from the computer and outputs it to the resonance circuit 50A. The resonance circuit 50A transmits the response signal 61 modulated by the modulation circuit 53 to the reader / writer 46 via the magnetic field MF. That is, when the response signal 61 is transmitted from the cartridge memory 24 to the reader / writer 46, the magnetic field MF includes the response signal 61. In other words, the magnetic field MF superimposes the response signal 61. In this embodiment, the command signal 48 is an example of a "command signal" according to the present disclosure, and the response signal 61 is an example of a "response signal" according to the present disclosure.

[0060] The computer 54 controls the entire cartridge memory 24. As shown in FIG. 6 as an example, the computer 54 includes a processor 54A, an NVM 54B, and a RAM 54C. The processor 54A is, for example, a CPU. The NVM 54B is, for example, a non-volatile memory such as an EEPROM and / or a ferroelectric memory. The RAM 54C is a volatile memory such as a DRAM, and is used as a work memory by the processor 54A. The processor 54A, the NVM 54B, and the RAM 54C are connected to a bus 64. A demodulation circuit 52 is also connected to the bus 64, and a command signal 48 is supplied from the demodulation circuit 52 to the processor 54A. A modulation circuit 53 is also connected to the bus 64, and a response signal 61 is supplied from the processor 54A to the modulation circuit 53. In this embodiment, the processor 54A is an example of a "processing circuit" according to the present disclosure, and the NVM 54B is an example of a "memory" according to the present disclosure.

[0061] The processor 54A selectively executes a write process and a read process on the NVM 54B as a process in response to the command signal 48. That is, when the processor 54A executes a write process, information determined in response to the command signal 48 is written to the NVM 54B, and when the processor 54A executes a read process, information determined in response to the command signal 48 among the information stored in the NVM 54B is read from the NVM 54B. In the example shown in FIG. 6, an example of a mode in which management information 15 is stored in the NVM 54B is shown, and the processor 54A writes the management information 15 to the NVM 54B or reads the management information 15 from the NVM 54B in response to the command signal 48.

[0062] The command signal 48 is a waveform signal, and is transmitted to the cartridge memory 24 by the reader / writer 46 via the magnetic field MF. The resonant circuit 50A resonates upon receiving the magnetic field MF transmitted from the reader / writer 46, and generates an AC voltage 56A indicative of the command signal 48. The AC voltage 56A is included in the concept of the AC voltage 56 shown in FIG. 5. The demodulation circuit 52 extracts and demodulates the command signal 48 from the resonant circuit 50A, and outputs the demodulated command signal 48 (for example, a binarized signal) to the processor 54A.

[0063] The processor 54A executes processing according to the command signal 48 input from the demodulation circuit 52. The processor 54A also outputs the processing result to the modulation circuit 53 as a response signal 61, which is a waveform signal (for example, a binarized signal). The modulation circuit 53 modulates the response signal 61 input from the processor 54A and supplies it to the resonant circuit 50A. The resonant circuit 50A generates an AC voltage 56B indicating the response signal 61 input from the modulation circuit 53. The AC voltage 56B is included in the concept of the AC voltage 56 shown in FIG. 5. The resonant circuit 50A transmits the response signal 61 modulated by the modulation circuit 53 to the reader / writer 46 via the magnetic field MF.

[0064] In this manner, non-contact communication between the cartridge memory 24 and the reader / writer 46 is realized by transmitting the command signal 48 and the response signal 61 through space via the magnetic field MF.

[0065] Incidentally, in order to stabilize non-contact communication between the cartridge memory 24 and the reader / writer 46, it is desirable that the waveforms of the command signal 48 and the response signal 61 are undistorted waveforms conforming to a communication method (for example, a method conforming to a known standard such as ISO14443 or ISO18092, or a method conforming to the LTO specification of ECMA319). If the waveforms of the command signal 48 and the response signal 61 are undistorted waveforms, the processor 54A can accurately identify the contents of the command signal 48, and the reader / writer 46 can accurately identify the contents of the response signal 61.

[0066] Since the cartridge memory 24 is a passive non-contact communication medium without a battery, it is necessary to generate power 60 by utilizing the magnetic field MF from the reader / writer 46 and supply the power 60 to various circuits such as the computer 54. Here, the shorter the distance between the cartridge memory 24 and the reader / writer 46, the more excessive AC voltage 56 is generated by the resonance circuit 50A. Accordingly, when an excessive DC voltage 58 is supplied to the regulator 50C from the rectifier circuit 50B, the regulator 50C generates excessive power 60. For this reason, as shown in FIG. 7 as an example, the regulator 50C is connected to the ground potential GND, and the generated excess power is released to the ground potential GND as leakage power 59, thereby supplying the regulated power 60 to various circuits such as the computer 54.

[0067] Here, assuming that the resistance value of the modulation circuit 53 is constant, if the escape current 59 is small, the current flowing through the modulation circuit 53 during modulation of the modulation circuit 53 is not drawn to the regulator 50C and becomes large, and conversely, if the escape current 59 is large, the current flowing through the modulation circuit 53 during modulation of the modulation circuit 53 is drawn to the regulator 50C and becomes small. The smaller the escape current 59, the larger the current flowing to the ground potential GND through the modulation circuit 53 during modulation, so the deeper the modulation depth of the response signal 61 (i.e., the difference between the maximum amplitude of the response signal 61 and the minimum amplitude of the response signal 61). Conversely, the larger the escape current 59, the smaller the current flowing to the ground potential GND through the modulation circuit 53 during modulation of the response signal 61, so the shallower the modulation depth of the response signal 61. The shorter the distance between the cartridge memory 24 and the reader / writer 46, the shallower the modulation depth of the response signal 61. The modulation depth of the response signal 61 also becomes shallow depending on the specifications of the antenna coil 50A1 and / or the specifications of an antenna coil (not shown) mounted on the reader / writer 46. When the modulation depth of the response signal 61 becomes shallow, it becomes difficult for the reader / writer 46 to read the contents of the response signal 61 acquired from the cartridge memory 24 via the magnetic field MF. For example, the shallower the modulation depth of the response signal 61, the more likely it is that the reader / writer 46 will misread it if noise is mixed into the response signal 61.

[0068] On the other hand, the longer the distance between the cartridge memory 24 and the reader / writer 46, the deeper the modulation depth of the response signal 61. The deeper the modulation depth of the response signal 61, the deeper the modulation depth 56B1 of the AC voltage 56B (i.e., the difference between the maximum amplitude of the AC voltage 56B and the minimum amplitude of the AC voltage 56B). The modulation depth of the response signal 61 also becomes deeper depending on the specifications of the antenna coil 50A1 and / or the specifications of the antenna coil (not shown) mounted on the reader / writer 46. The deeper the modulation depth 56B1 of the AC voltage 56B, the smaller the DC voltage 58 generated by the rectifier circuit 50B becomes, and the power 60 generated by the regulator 50C becomes insufficient. For example, if the modulation depth 56B1 of the AC voltage 56B is too deep, a power outage occurs in the cartridge memory 24. In other words, if the modulation depth 56B1 of the AC voltage 56B is too deep, the DC voltage 58 generated by the rectifier circuit 50B will become zero, and while the DC voltage 58 is zero, the supply of power 60 to the various circuits of the cartridge memory 24 will be cut off.

[0069] In view of such circumstances, in this embodiment, as an example shown in Fig. 8, the cartridge memory 24 includes a modulation circuit 53, a monitoring circuit 69, and a control circuit 70. The modulation circuit 53 is a circuit that modulates the AC voltage 56B. The monitoring circuit 69 is a circuit that monitors the escape power 59 released from the regulator 50C. The control circuit 70 is a circuit that controls the modulation circuit 53 based on a monitoring result 76 by the monitoring circuit 69.

[0070] The monitoring circuit 69 and the control circuit 70 are realized by an ASIC. However, this is merely an example, and the monitoring circuit 69 and / or the control circuit 70 may be realized by an FPGA and / or a PLD. The monitoring circuit 69 and / or the control circuit 70 may be realized by a computer including a CPU, an NVM, and a RAM. The monitoring circuit 69 and / or the control circuit 70 may be realized by a combination of two or more of the ASIC, the FPGA, the PLD, and the computer. That is, the monitoring circuit 69 and / or the control circuit 70 may be realized by a combination of a hardware configuration and a software configuration.

[0071] The modulation circuit 53 has a variable resistor 72 and a switch 74. Here, the variable resistor 72 is an example of a "variable resistor" according to the present disclosure, and the switch 74 is an example of a "switch" according to the present disclosure.

[0072] The variable resistor 72 is connected to the resonant circuit 50A. The variable resistor 72 has variable resistance elements 72A and 72B. The variable resistance elements 72A and 72B are an example of a "pair of variable resistance elements" according to the present disclosure. The variable resistance elements 72A and 72B are connected in parallel to the resonant circuit 50A. In the example shown in FIG. 8, one end of the variable resistance element 72A is connected to one end of the antenna coil 50A1 and one end of the variable capacitor 50A2, and one end of the variable resistance element 72B is connected to the other end of the antenna coil 50A1 and the other end of the variable capacitor 50A2.

[0073] The switch 74 switches between an application state (hereinafter also simply referred to as an "application state") in which the load (in other words, resistance value) of the variable resistor 72 is applied to the resonant circuit 50A and a non-application state (hereinafter also simply referred to as a "non-application state") in which the load of the variable resistor 72 is not applied to the resonant circuit 50A, according to the response signal 61. The switch 74 corresponds to the variable resistance elements 72A and 72B, and is a pair of switches capable of connecting the variable resistance elements 72A and 72B to the ground potential GND. In the example shown in FIG. 8, switches 74A and 74B are shown as an example of a pair of switches. The switches 74A and 74B are an example of a "pair of switches" according to the present disclosure.

[0074] One end of the switch 74A is connected to the other end of the variable resistance element 72A, and the other end of the switch 74A is connected to the ground potential GND. One end of the switch 74B is connected to the other end of the variable resistance element 72B, and the other end of the switch 74B is connected to the ground potential GND.

[0075] The switch 74A switches between a first connection state in which the variable resistance element 72A is connected to the ground potential GND and a first non-connection state in which the variable resistance element 72A is not connected to the ground potential GND under the control of the computer 54. In the example shown in FIG. 8, the response signal 61 is a signal indicating "0" or "1", and the switch 74A switches between the first connection state and the first non-connection state according to the response signal 61. For example, the switch 74A is in the first connection state if the response signal 61 is a signal indicating "0", and is in the first non-connection state if the response signal 61 is a signal indicating "1". Note that this switching example is merely an example, and for example, the switch 74A may be in the first connection state if the response signal 61 is a signal indicating "1", and in the first non-connection state if the response signal 61 is a signal indicating "0".

[0076] The switch 74B switches between a second connection state in which the variable resistance element 72B is connected to the ground potential GND and a second non-connection state in which the variable resistance element 72B is not connected to the ground potential GND under the control of the computer 54. In the example shown in FIG. 8, the switch 74B switches between the second connection state and the second non-connection state according to the response signal 61. For example, the switch 74B is in the second connection state if the response signal 61 is a signal indicating "0", and is in the second non-connection state if the response signal 61 is a signal indicating "1". Note that this switching example is merely an example, and for example, the switch 74B may be in the second connection state if the response signal 61 is a signal indicating "1", and in the second non-connection state if the response signal 61 is a signal indicating "0".

[0077] The first connection state is realized by turning on the switch 74A, and the first non-connection state is realized by turning off the switch 74A. The second connection state is realized by turning on the switch 74B, and the second non-connection state is realized by turning off the switch 74B. The switches 74A and 74B are switched on and off according to the response signal 61. For example, if the response signal 61 is a signal indicating "0", the switches 74A and 74B are turned on, and if the response signal 61 is a signal indicating "1", the switches 74A and 74B are turned off. By turning on the switches 74A and 74B, the resonant circuit 50A is connected to the ground potential GND via the variable resistor 72, so that a part of the power of the resonant circuit 50A flows to the ground potential GND. When the switches 74A and 74B are turned on and the variable resistor 72 is connected to the ground potential GND, the load of the variable resistance elements 72A and 72B is applied to the resonant circuit 50A. The state in which a load is applied to the resonant circuit 50A is released by turning off the switches 74A and 74B. That is, the load application state is realized when the switches 74A and 74B are turned on in response to the response signal 61, and the non-load application state is realized when the switches 74A and 74B are turned off in response to the response signal 61.

[0078] The monitoring circuit 69 monitors the runaway power 59 released from the regulator 50C to generate the power 60, and outputs a monitoring result 76 to the control circuit 70. The control circuit 70 controls the resistance value of the variable resistor 72 (i.e., the resistance values ​​of the variable resistance elements 72A and 72B) according to the monitoring result 76 input from the monitoring circuit 69. For example, when the runaway power 59 increases, the control circuit 70 decreases the resistance value of the variable resistor 72 in accordance with the increase in the runaway power 59, and when the runaway power 59 decreases, the control circuit 70 increases the resistance value of the variable resistor 72 in accordance with the decrease in the runaway power. The load of the variable resistor 72 applied to the resonant circuit 50A is changed by changing the load of the variable resistor 72 applied to the resonant circuit 50A in accordance with the runaway power 59, thereby adjusting the modulation depth of the AC voltage 56B.

[0079] Here, the modulation of the AC voltage 56B refers to, for example, changing the height difference of the waveform of the AC voltage 56B. Changing the height difference of the waveform of the AC voltage 56B refers to, for example, changing the amplitude of the AC voltage 56B to reduce or increase the difference between the maximum amplitude and the minimum amplitude of the AC voltage 56B (i.e., making the modulation depth 56B1 of the AC voltage 56 shallower or deeper). The amplitude of the AC voltage 56B is changed by applying a load of the variable resistor 72 to the resonant circuit 50A and controlling the load. For example, when the load of the variable resistor 72 applied to the resonant circuit 50A is changed, the amplitude of the AC voltage 56B is changed accordingly (i.e., the height difference of the waveform of the AC voltage 56B changes). By changing the amplitude of the AC voltage 56B, the magnitude of the DC voltage 58 generated by the rectifier circuit 50B is also changed. This allows regulator 50C to generate optimal power 60 that keeps the modulation depth (in other words, the modulation degree) of response signal 61 constant (i.e., power 60 that enables stable supply of power 60 to various circuits such as computer 54 and enables reader / writer 46 to accurately read the contents of response signal 61).

[0080] Next, the operation of the magnetic tape system 10 according to the present disclosure will be described with reference to Fig. 9. The flowchart shown in Fig. 9 is an example of a "method of operating a non-contact communication medium" according to the present disclosure.

[0081] In the modulation process shown in Fig. 9, first, in step ST10, the processor 54A judges whether or not the command signal 48 has been received by the demodulation circuit 52. If the command signal 48 has not been received by the demodulation circuit 52 in step ST10, the judgment is negative, and the modulation process proceeds to step ST20. If the command signal 48 has been received by the demodulation circuit 52 in step ST10, the judgment is positive, and the modulation process proceeds to step ST12. If the command signal 48 has been received by the demodulation circuit 52, the command signal 48 is demodulated by the demodulation circuit 52.

[0082] In step ST12, the processor 54A generates a response signal 61 in response to the command signal 48 demodulated by the demodulation circuit 52. After the process of step ST12 is executed, the modulation process proceeds to step ST14.

[0083] In step ST14, the resonant circuit 50A generates an AC voltage 56B in response to the response signal 61 generated by the processor 54A. After the process of step ST14 is performed, the modulation process proceeds to step ST16.

[0084] In step ST16, the switch 74 switches between the grant state and the non-grant state in response to the response signal 61 generated by the processor 54A. That is, the grant state and the non-grant state are switched by switching the switches 74A and 74B on and off in response to the response signal 61. After the process of step ST16 is executed, the modulation process proceeds to step ST18.

[0085] In step ST18, the control circuit 70 controls the resistance value of the variable resistor 72 in response to the run-off power 59. With the switches 74A and 74B turned on, the resistance value of the variable resistor 72 is changed, thereby changing the degree of modulation of the AC voltage 56B. That is, the modulation depth 56B1 of the AC voltage 56B is changed.

[0086] Here, the processing contents of step ST18 will be described in more detail. The stray power 59 is linked to the modulation depth 56B1 of the AC voltage 56B, and the modulation depth 56B of the AC voltage 56B can be specified from the stray power 59. The deeper the modulation depth 56B1 of the AC voltage 56B is within a range equal to or greater than a predetermined depth level, the smaller the DC voltage 58 generated by the rectifier circuit 50B becomes, and the more insufficient the power 60 generated by the regulator 50C becomes. Conversely, the shallower the modulation depth 56B1 of the AC voltage 56B is within a range below the predetermined depth level, the more difficult it becomes for the reader / writer 46 to decode the response signal 61 transmitted from the cartridge memory 24 to the reader / writer 46.

[0087] Therefore, in this step ST18, the monitoring circuit 69 measures the runaway power 59, determines whether the measured runaway power 59 is greater than or equal to a certain level, and if the measured runaway power 59 is greater than or equal to the certain level, specifies how much greater the runaway power 59 is from the certain level. Also, if the measured runaway power 59 is less than the certain level, the monitoring circuit 69 specifies how much smaller the runaway power 59 is from the certain level.

[0088] The fact that the escaping power 59 is large above a certain level means that the DC voltage 58 input to regulator 50C is excessively large (in other words, it means that the modulation depth 56B1 of the AC voltage 56B is too shallow). In this case, in this step ST18, the control circuit 70 reduces the resistance value of the variable resistor 72 so that the magnitude of the DC voltage 58 input to regulator 50C is optimized (i.e., reduces the resistance value of the variable resistor 72 so that the magnitude of the DC voltage 58 input to regulator 50C becomes a predetermined voltage level). Furthermore, the fact that the stray power 59 is small and below a certain level means that the DC voltage 58 input to the regulator 50C is excessively small (in other words, the modulation depth 56B1 of the AC voltage 56B is too deep), so in this case, in this step ST18, the control circuit 70 increases the resistance value of the variable resistor 72 so that the magnitude of the DC voltage 58 input to the regulator 50C becomes optimal (i.e., increases the resistance value of the variable resistor 72 so that the magnitude of the DC voltage 58 input to the regulator 50C becomes a predetermined voltage level). In other words, the resistance value of the variable resistor 72 is controlled by the control circuit 70 so that the magnitude of the DC voltage 58 input to the regulator 50C is maintained at a predetermined voltage level.

[0089] In this step ST18, the modulation depth 56B1 of the AC voltage 56B is changed by controlling the resistance value of the variable resistor 72. Here, the control amount of the resistance value of the variable resistor 72 by the control circuit 70 is determined according to the runaway power 59 measured by the monitoring circuit 69. This is because the runaway power 59 is linked to the modulation depth 56B of the AC voltage 56B, and there is a corresponding relationship between the runaway power 59 and the modulation depth 56B of the AC voltage 56B. After the process of step ST18 is executed, the modulation process proceeds to step ST20.

[0090] In step ST20, the processor 54A determines whether or not a condition for terminating the modulation process is satisfied. Examples of the condition for terminating the modulation process include a condition that the voltage value of the AC voltage 56B or the voltage value of the DC voltage 58 remains "zero" for a certain period of time or more, or a condition that a command to terminate the modulation process is given as a command signal 48 from the reader / writer 46.

[0091] In step ST20, if the condition for terminating the modulation process is not satisfied, the determination is negative and the modulation process proceeds to step ST10. In step ST20, if the condition for terminating the modulation process is satisfied, the determination is positive and the modulation process ends.

[0092] As described above, in this embodiment, the switch 74 switches between an applied state in which the load of the variable resistor 72 is applied to the resonant circuit 50A and a non-applied state in which the load of the variable resistor 72 is not applied to the resonant circuit 50A in response to the response signal 61. In the applied state, the resonant circuit 50A is connected to the ground potential GND via the variable resistor 72, so the applied state can be said to be a state in which the AC voltage 56B can be modulated (i.e., a state in which a change in the load of the variable resistor 72 can be reflected in the modulation of the AC voltage 56B). In the non-applied state, the resonant circuit 50A is not connected to the ground potential GND via the variable resistor 72, so the non-applied state can be said to be a state in which the AC voltage 56B cannot be modulated (i.e., a state in which a change in the load of the variable resistor 72 cannot be reflected in the modulation of the AC voltage 56B).

[0093] Then, in the applied state, the resistance value of the variable resistor 72 is controlled according to the escape power 59 released from the regulator 50C to generate the power 60. By changing the resistance value of the variable resistor 72 in the applied state, the degree of modulation of the AC voltage 56B is changed. That is, the modulation depth 56B1 of the AC voltage 56B is changed. This makes it possible to prevent the occurrence of a situation in which the modulation depth 56B1 of the AC voltage 56B becomes extremely deep or extremely shallow (for example, the modulation depth 56B1 of the AC voltage 56 can be maintained at a predetermined depth level).

[0094] As a result, the supply of power 60 to various circuits such as the computer 54 can be stabilized, and the reader / writer 46 can be made to accurately read the contents of the response signal 61 (i.e., the result obtained when the processor 54A executes the process according to the command signal 48 provided from the reader / writer 46). In addition, since the supply of power 60 to the processor 54A can be stabilized, it is possible to prevent the occurrence of a situation in which the processor 54A is unable to write the management information 15 to the NVM 54B and / or the processor 54A is unable to read the management information 15 from the NVM 54B due to an insufficient supply of power 60 to the processor 54A.

[0095] In this embodiment, a pair of variable resistance elements, i.e., variable resistance elements 72A and 72B, are connected to the resonant circuit 50A. A pair of switches, i.e., switches 74A and 74B, connected to the ground potential GND, are connected to the variable resistance elements 72A and 72B. A load-applied state in which the variable resistor 72 is applied to the resonant circuit 50A is realized when the switches 74A and 74B are turned on, and a non-applied state in which the variable resistor 72 is not applied to the resonant circuit 50A is realized when the switches 74A and 74B are turned off. Therefore, it is possible to switch between a load-applied state in which the variable resistor 72 is applied to the resonant circuit 50A and a non-applied state in which the variable resistor 72 is not applied to the resonant circuit 50A with a simple configuration.

[0096] In addition, in this embodiment, when the runaway power 59 increases, the resistance value of the variable resistor 72 is increased in accordance with the increase in the runaway power 59, and when the runaway power 59 decreases, the resistance value of the variable resistor 72 is decreased in accordance with the decrease in the runaway power 59. This allows a load according to the runaway power 59 to be applied to the resonant circuit 50A. As a result, it is possible to accurately balance the supply of power 60 to various circuits such as the computer 54 and the like and to allow the reader / writer 46 to accurately read the contents of the response signal 61, as compared to a case in which the load applied to the resonant circuit 50A is increased or decreased without reference to the runaway power 59 at all.

[0097] In the above embodiment, the monitoring circuit 69 and the control circuit 70 are realized by an ASIC. However, the present disclosure is not limited to this. The monitoring circuit 69 and the control circuit 70 may be realized by a software configuration. In this case, for example, as shown in FIG. 10, a computer 78 is applied instead of the monitoring circuit 69 and the control circuit 70. The computer 78 has a processor 78A. The computer 78 also has an NVM 78B, which is a computer-readable non-transitory storage medium. A program 80 is stored in the NVM 78B. The processor 78A reads the program 80 from the NVM 78 and operates as the monitoring circuit 69 and the control circuit 70 according to the program 80. In this way, even if the computer 78 is applied instead of the monitoring circuit 69 and the control circuit 70, the same effect as the above embodiment can be obtained. In the example shown in FIG. 10, the computer 78 is an example of a "computer" according to the present disclosure, and the program 80 is an example of a "program" according to the present disclosure.

[0098] In the above embodiment, a cartridge memory 24 that communicates with a reader / writer 46 in a non-contact manner is used as an example, but the present disclosure is not limited to this, and the present disclosure is also applicable to non-contact communication media other than the cartridge memory 24 (for example, a passive RFID tag used in a technical field different from this technical field).

[0099] In the above embodiment, the reader / writer 46 mounted on the magnetic tape drive 14 is exemplified, but the present disclosure is not limited to this, and may be a reader / writer other than the reader / writer 46 (for example, a reader / writer used in a technical field different from the present technical field). Also, it may be an external device that writes or reads by communicating in a non-contact manner with the non-contact communication medium to which the present disclosure is applied.

[0100] In the above embodiment, a stationary reader / writer (i.e., a reader / writer mounted on the magnetic tape drive 14) is exemplified as the reader / writer 46, but this is merely an example, and the present disclosure also applies to a portable reader / writer. In addition, the stationary or portable reader / writer may be a reader / writer used in a technical field different from the present technical field.

[0101] In the above embodiment, the magnetic tape system 10 in which the magnetic tape cartridge 12 is freely insertable into and removable from the magnetic tape drive 14 has been exemplified, but the present disclosure is not limited thereto. For example, the present disclosure can also be applied to a magnetic tape system in which at least one magnetic tape cartridge 12 is preloaded into the magnetic tape drive 14 (i.e., a magnetic tape system in which at least one magnetic tape cartridge 12 and the magnetic tape drive 14, or a magnetic tape MT and the magnetic tape drive 14, are integrated in advance (for example, before data is recorded on a data band)).

[0102] In the above embodiment, an example was given in which the variable resistor 72 has variable resistance elements 72A and 72B, but this is merely one example, and a circuit (e.g., a circuit having a variable capacitor and a transistor, etc.) having the same function as the variable resistor 72 (i.e., the function of applying a changeable load to the resonant circuit 50A) may also be used.

[0103] The above description and illustrations are detailed descriptions of the parts related to the present disclosure and are merely an example of the present disclosure. For example, the above description of the configuration, function, action, and effect is an example of the configuration, function, action, and effect of the parts related to the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above description and illustrations within the scope of the gist of the present disclosure. In addition, in order to avoid confusion and to facilitate understanding of the parts related to the present disclosure, the above description and illustrations omit explanations of technical common sense that do not require explanation in order to enable the implementation of the present disclosure.

[0104] In this specification, "A and / or B" is synonymous with "at least one of A and B." In other words, "A and / or B" means that it may be only A, only B, or a combination of A and B. In addition, in this specification, the same idea as "A and / or B" is also applied when three or more things are expressed by connecting them with "and / or."

[0105] All publications, patent applications, and standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or standard was specifically and individually indicated to be incorporated by reference. [Explanation of symbols]

[0106] 10 Magnetic Tape Systems 12 Magnetic Tape Cartridge 14 Magnetic Tape Drives 15 Management information 16 cases 16A Right wall 16A1 Aperture 22 Sending reel 24 Cartridge Memory 25 Controller 26 Transport Equipment 28 Magnetic Head 29 UI devices 30 Processing equipment 31 Surface 32 Storage 36 Delivery motor 38 Take-up reel 40 Winding motor 42 Magnetic element unit 44 Holder 46 Reader / Writer 48 Command Signals 50 power generator 50A resonant circuit 50A1 Antenna coil 50A2 variable capacitor 50B rectifier circuit 50C Regulator 52 Demodulation circuit 53 Modulation circuit 54,78 Computer 54A,78A Processor 54B,78B NVM 54C RAM 56, 56A, 56B AC voltage 58 DC Voltage 59 Run-off power 60 electric power 61 Response Signal 64 Bus 68A,68B signal 69 Monitoring circuit 70 Control circuit 72 Variable resistor 72A, 72B Variable resistance element 74 Switch 74A, 74B Switch 76 Monitoring results 80 Programs A,B,C arrows GND Ground potential MF magnetic field MT magnetic tape

Claims

1. A non-contact communication medium that communicates with an external device in a non-contact manner via a magnetic field applied from the external device, a resonant circuit that generates an AC voltage by resonating with an induced current induced by an antenna coil when the magnetic field acts on the antenna coil; a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage; a variable resistor connected to the resonant circuit; A switch and A control circuit, the processing circuit generates a response signal in response to a command signal provided from the external device via the magnetic field; the switch switches between an applied state in which the load of the variable resistor is applied to the resonant circuit and a non-applied state in which the load is not applied to the resonant circuit in response to the response signal; The control circuit controls the resistance value of the variable resistor in response to the leakage power released from the regulator to generate the operating power. Contactless communication medium.

2. The processing circuitry includes: Execute a process in response to the command signal; A signal indicating the result obtained by executing the process is output as the response signal. The non-contact communication medium according to claim 1 .

3. the variable resistor is a pair of variable resistance elements connected to the resonant circuit, the switches are a pair of switches corresponding to the pair of variable resistance elements and capable of connecting the pair of variable resistance elements to a ground potential, The application state is realized when the pair of switches are turned on, The non-applied state is realized when the pair of switches are turned off. The non-contact communication medium according to claim 1 .

4. The control circuit includes: When the run-off power increases, the resistance value is reduced in accordance with the increase in the run-off power; When the run-off power is reduced, the resistance value is increased in accordance with the reduction in the run-off power. The non-contact communication medium according to claim 1 .

5. A memory to which the processing circuit writes information and / or from which the processing circuit reads information is provided. The non-contact communication medium according to claim 1 .

6. The non-contact communication medium is mounted on a magnetic tape cartridge. The non-contact communication medium according to claim 1 .

7. A magnetic tape cartridge comprising the non-contact communication medium according to any one of claims 1 to 6.

8. A non-contact communication medium according to any one of claims 1 to 6; The external device. Contactless communication system.

9. 1. A method for operating a non-contact communication medium that communicates with an external device in a non-contact manner via a magnetic field applied from the external device, comprising: The non-contact communication medium is a resonant circuit that generates an AC voltage by resonating with an induced current induced by an antenna coil when the magnetic field acts on the antenna coil; a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage; a variable resistor connected to the resonant circuit; A switch and A control circuit, the processing circuit generates a response signal in response to a command signal provided from the external device via the magnetic field; The switch switches between a load state in which the variable resistor is applied to the resonant circuit and a non-load state in which the load is not applied to the resonant circuit in response to the response signal; and The control circuit controls a resistance value of the variable resistor in response to a leakage power released from the regulator for generating the operating power. A method of operation of a contactless communication medium.

10. A program for causing a computer provided in a non-contact type communication medium that communicates with an external device in a non-contact manner via a magnetic field provided by the external device to execute a modulation process, The non-contact communication medium is a resonant circuit that generates an AC voltage by resonating with an induced current induced by an antenna coil when the magnetic field acts on the antenna coil; a regulator that generates operating power for operating a processing circuit from power based on a DC voltage obtained by rectifying the AC voltage; a variable resistor connected to the resonant circuit; A switch, the processing circuit generates a response signal in response to a command signal provided from the external device via the magnetic field; the switch switches between an applied state in which the load of the variable resistor is applied to the resonant circuit and a non-applied state in which the load is not applied to the resonant circuit in response to the response signal; The modulation process includes a process of controlling a resistance value of the variable resistor in response to a leakage power released from the regulator for generating the operating power. program.

Images