JP5022972B2 - External communication apparatus and centralized control apparatus for performing wireless communication with information recording medium - Google Patents

Description

  The present invention relates to an RFID system including a reader / writer that is an external communication device that performs wireless communication with an information recording medium including a so-called RFID tag. In particular, when a plurality of external communication devices are provided, the present invention relates to control of each external communication device.

  In recent years, in the fields of supply chain management and article management in distribution and sales, an information recording medium having a communication distance of several meters or more and capable of simultaneously recognizing several tens or more, that is, an RFID tag has been popularized. .

  The RFID tag performs a wireless communication with an external communication device, that is, a reader / writer, and functions to read the information of the RFID tag, write the information, lock the reading or writing, and disable the RFID tag. Have.

  When a reader / writer performs wireless communication with an RFID tag, the frequency band of radio waves that can be used is limited, and a plurality of reader / writers cannot use the same frequency band at the same time, that is, perform wireless communication with an RFID tag. I can't. Note that “simultaneous” and “same frequency band” do not have to match at all.

  In an RFID tag system using a plurality of reader / writers, when the number of reader / writers used simultaneously is larger than the number of usable frequency bands, each reader / writer cannot simultaneously communicate with the RFID tag wirelessly, and the RFID tag system. May not function properly. Therefore, in the RFID tag system, it is required to improve the accuracy of wireless communication between the reader / writer and the RFID tag.

  For example, in Patent Document 1, the reader / writer to which the frequency band is assigned in a one-to-one relationship is changed at regular time intervals, and the assigned time is assigned to one reader / writer by sequentially assigning the frequency band to each reader / writer. A method has been proposed in which a writer occupies the frequency band and performs reading.

JP 2006-148258 A

  The RFID tag has functions such as writing and locking in addition to reading. These functions, including the reading function, usually have different priorities. In the RFID tag system, when the reader / writer repeats the reading process and the RFID tag enters the radio wave range, the RFID tag information is acquired.

  In addition, writing, locking, or high priority processing other than the above reading processing may be performed at an arbitrary timing. The function of writing or locking is not repeatedly performed as in the reading process, but can be executed by the user at an arbitrary timing, and writing or locking must be surely executed.

  Therefore, the user can perform other high-priority processing at any timing while maintaining the accuracy of the RFID tag system by executing a function that is executed in a time-shifted manner in each of a plurality of devices (reader / writers). Means are needed.

  Therefore, in the present invention, the functions that are executed while being shifted in time in each of the plurality of reader / writers are executed according to schedule data stored in advance. In particular, this function includes repeated execution. In addition, this function includes reading information from RFID tags in the same frequency band by each of the plurality of reader / writers. In the present invention, a single reader / writer may be controlled. For example, when a single reader / writer performs wireless communication in a plurality of frequency bands, schedule data is generated in each frequency band.

  The schedule data is stored in a centralized control device connected to each reader / writer, and each reader / writer executes the above function according to control information (based on the schedule data) transmitted from the centralized control device.

  In addition, the schedule data includes the start time information indicating the start time of the wireless communication of each reader / writer and the interval time information indicating the interval (cycle) of the start time of the wireless communication. Further, the present invention includes the end time information indicating the end time of the wireless communication of each reader / writer and the interval time information indicating the interval between the end time and the next start time information for starting the next wireless communication. It is.

  Further, the schedule data is registered in the storage device. (1) Among the reader / writers, those having the same frequency band are extracted. (2) In each of the extracted reader / writers, the interval time information is a constant value. It is also included in one embodiment of the present invention to set and register such that

  Furthermore, when the reader / writer or the centralized control device accepts a request for a function that is not defined by the schedule data, the function accepted by the function specified by the schedule data is executed. At this time, (1) the function specified in the schedule data is canceled and the accepted function is executed, and (2) the schedule function that is being executed when the request is accepted until the function specified is temporarily terminated. The received function may be executed before the next function is executed.

  According to the present invention, each function can be controlled more efficiently in the RFID system.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments relating to the present invention will be described below with reference to an external communication device reader / writer, an information recording medium RFID tag, and a centralized control device that centrally controls or manages a plurality of external communication device reader / writers. 1 shows the configuration of the information recording medium RFID tag in FIG. 2, the configuration of the external communication device reader / writer in FIG. 3, the configuration of the central control device in FIG. 4, and the external communication device reader / writer communicates with the information recording medium RFID tag. FIG. 5 shows a process for performing the process, and FIG. 6 to FIG. 9 show a method in which the central control apparatus controls a plurality of external communication apparatus reader / writers based on the schedule data and repeats the RFID tag reading process. Controls multiple external communication device readers / writers based on the above and executes interrupt processing while repeating RFID tag reading processing Law in Figures 10-12 and will be described with reference to the drawings. In the present embodiment, a plurality of reader / writers are controlled by the centralized control apparatus, but each reader / writer may be configured to control each reader / writer.

  FIG. 1 shows a configuration comprising an RFID tag system comprising an external communication device reader / writer and an information recording medium RFID tag according to the present embodiment, and a centralized control device for centrally controlling or managing a plurality of external communication device reader / writers. FIG. Hereinafter, the external communication device reader / writer is referred to as a reader / writer, and the information recording medium RFID tag is referred to as an RFID tag.

  A basic RFID tag system includes an RFID tag 100 and a reader / writer 200. The reader / writer 200 outputs a radio wave to the reader / writer main body 201 that performs control for transmitting and receiving the RFID tag 100, the RFID tag command data 300 and the RFID tag response data 301, and the RFID tag command data 300 and The reader / writer antenna 202 transmits and receives the RFID tag response data 301. The reader / writer 200 transmits the RFID tag command data 300 for communication with the RFID tag 100 by radio waves to the RFID tag 100 and supplies power, and the reader / writer 200 receives the RFID tag response which is a response of the RFID tag 100. Data 301 is received.

  The central control device 400 is connected to a plurality of reader / writers 200. In FIG. 1, the central control device 400 is connected to two reader / writers 200 and 210, but may be connected to any number. For convenience of illustration, two units are provided. The reader / writer 200 and the reader / writer 210 have the same configuration.

  The centralized control device 400 is connected to the reader / writer 200 and transmits reader / writer command data 302 for communicating with the reader / writer 200 to the reader / writer 200. The reader / writer 200 executes processing corresponding to the reader / writer command data 302 from the central control device 400 and returns the reader / writer response data 303. Similarly, the same processing is performed for the reader / writer 210. The centralized control device 400 transmits the reader / writer command data 302 and the reader / writer response data 303 to a plurality of reader / writers simultaneously or sequentially. The central control device 400 may be included in any or all of the reader / writers.

  FIG. 2 is a block diagram showing the internal configuration of the RFID tag 100. The RFID tag 100 receives radio waves from a reader / writer, transmits and receives signals and data to and from the reader / writer, an rectifier 102 that rectifies radio waves received from the antenna 101, and a voltage obtained by rectification. A power supply unit 103 that detects and supplies power to each unit; a communication control unit 104 that demodulates received signals and RFID tag command data; and that modulates signals to be transmitted and RFID tag command data; and initialization processing and RFID It has a processing procedure for processing tag command data and access processing for each data item, and generates a response data in response to the reader / writer, the identification number of the RFID tag 100, other information, and the RFID tag 100 It is comprised from the memory | storage part 106 which memorize | stores a setting value.

  FIG. 3 is a diagram showing an internal configuration of the reader / writer 200. The reader / writer 200 transmits the RFID tag command data to the reader / writer main body 201 that performs control for transmitting and receiving data to and from the RFID tag, and outputs a radio wave, and receives a response from the RFID tag. The reader / writer antenna 202 is configured. The reader / writer main body 201 uses a reader / writer antenna 202 to transmit / receive RFID tag command data to / from an RFID tag, and to receive / receive a response from the transmitter / receiver 203. At the time of modulation and reception of RFID tag command data A communication control unit 204 having a communication method for controlling, a control unit 205 for controlling the entire reader / writer, a power source unit 206 for supplying power to each unit, a reader / writer A main body 201 and a host interface 207 for communicating data, reader / writer command data, and the like with an external communication device such as a central control device or a personal computer. Examples of RFID tag command data transmitted from the reader / writer to the RFID tag include an RFID tag read command when reading the RFID tag identification number and memory data, an RFID tag write command when writing data to the RFID tag memory, and RFID An RFID tag lock command is used to disable reading or rewriting of the tag memory data, and an RFID tag kill command is used to disable the RFID tag. Further, wireless communication with the RFID tag may be performed in a plurality of frequency bands.

  FIG. 4 is a diagram showing an internal configuration of the central control apparatus 400. The centralized control device 400 includes a reader / writer connection interface 401 for connecting to a plurality of reader / writers, a host interface 402 for connecting to an external communication device such as a personal computer, and a plurality of readers connected to the reader / writer connection interface. A control unit 403 that performs control of transmitting / receiving reader / writer command data to / from the writer and receiving reader / writer response data, and performing control of transmitting / receiving reader / writer command data and reader / writer response data to / from an external communication device, A power supply unit 404 that supplies power to the reader / writer, and a storage unit 405 that stores a processing method for controlling a plurality of reader / writers connected to the reader / writer connection interface 401 and setting values. Depending on the connection method with the reader / writer or the external communication device, the reader / writer connection interface 401 and the host interface 402 may be the same. As an example of the reader / writer command data transmitted to the reader / writer by the centralized control device 400, the reader / writer read command is used when reading the RFID tag identification number or memory data, and the reader / writer write command is used when writing data into the RFID tag memory. The reader / writer lock command is used to disable reading or rewriting of the RFID tag memory data, and the reader / writer kill command is used to disable the RFID tag. In this embodiment, a single centralized control device is configured for a plurality of reader / writers, but a control device having the same function as the centralized control device may be provided for each reader / writer.

  FIG. 5 is a diagram showing a flowchart of the reader / writer when communicating with the RFID tag. In step S500, initialization for communicating with the RFID tag and setting values related to communication are performed, and the process proceeds to step S501. In step S501, it is detected whether the frequency band that the reader / writer is about to output is not output by another reader / writer. If another reader / writer has already output a radio wave in that frequency band, the process proceeds to step S501. That is, the detection of radio waves is repeated. On the other hand, if the frequency band is not output by another reader / writer, the process proceeds to step S502. In step S502, radio wave output is turned on in a certain frequency band from the reader / writer antenna connected to the reader / writer, and the process proceeds to step S503. The RFID tag that has received the radio wave becomes a communication target with the reader / writer. In step S503, the RFID tag command data is transmitted to the RFID tag or the RFID tag response data is received. When the data transmission / reception is completed, the process proceeds to step S504. In step S504, the radio wave output from the reader / writer antenna in step S502 is turned off, and the process proceeds to step S505. In step S505, an end process is performed and the process ends.

  Next, a method for the centralized control apparatus to control the plurality of reader / writers in order for the RFID tag and the plurality of reader / writers to communicate normally will be described. The example will be described using an example in which three reader / writers are connected to one centralized control device, and three reader / writers periodically perform reading processing.

  FIG. 6 is a diagram showing schedule data at a timing when the central control apparatus periodically transmits a reader / writer read command to each reader / writer so that each reader / writer periodically reads the RFID tag. The centralized control device defines the transmission timing with a time slot. The time slot is generally in microsecond units because the processing of the RFID tag and the reader / writer is generally performed in units of several microseconds. However, depending on the time accuracy of the central control device or the reader / writer, It may be in seconds or a count. The start time slot value T1_600 indicates a time slot value at which the central control apparatus starts transmitting a reader / writer read command to each reader / writer. The interval time slot value T2_601 indicates a time slot value of an interval at which the reader / writer read command is periodically transmitted after the central control apparatus starts transmitting the reader / writer read command to each reader / writer. For the reader / writer 1, the start time slot value T1_600 is set to 1, and the interval time slot value T2_601 is set to 4. For the reader / writer 2, the start time slot value T1_600 is set to 1, and the interval time slot value T2_601 is set to 4. For the reader / writer 3, the start time slot value T1_600 is set to 4, and the interval time slot value T2_601 is set to 4. That is, the reader / writer 1 starts reading at time slot 1, and after four time slots have passed, performs reading processing at the timing of time slots 5, 9, and 13 counting from the start.

  The reader / writer 2 starts the reading process at the time slot 3, and after four time slots have passed, the reader / writer 2 performs the reading process at the timing of the time slots 7, 11, and 15 counted from the start time. The reader / writer 3 starts the reading process at the time slot 4, and after four time slots have passed, the reader / writer 3 performs the reading process at the timing of the time slots 8, 12, 16 counted from the start time. This schedule data is preferably stored in the storage unit of the centralized control device. Further, the schedule data may be transmitted from an external communication device connected to the host interface of the central control device at the start of processing of the central control device. In this example, the interval time slot value T2_601 is set as the interval of the reading process start time, but the timing is controlled as the interval time from the end of one reading process to the next reading process start time. Also good.

  A method for registering the schedule data will be described below (the central control apparatus executes each process). First, the frequency band of each reader / writer is registered in a reader / writer management table (not shown). This registration is executed by input from a terminal device connected in advance to the centralized control device. In the centralized control device, the reader / writer to be controlled this time is specified, and the reader / writer in the same frequency band (frequency band that functions by shifting the time band) is extracted from the reader / writer. Then, the central control apparatus registers each start time throttle value in accordance with an input from an administrator or the like and a preset priority order. Then, the centralized control device identifies the last one of the start time slot values (“4” of the reader / writer 3 in FIG. 6). Then, the value of “4” or more of the specified start time slot is written in each of the interval time slot values. When the interval time slot value (“4”) is added to the first start time slot value (“1” of the reader / writer 1), this exceeds the last start time slot value (“4” of the reader / writer 3). Set as follows. Among them, the reader / writer can be operated efficiently if it is set to exceed the minimum unit. In other words, the first start time slot value (“1” of reader / writer 1) is subtracted from the last start time slot value (“4” of reader / writer 3), and “1” is added to the interval time slot value (“4”). )). That is, a fixed time slot value is registered for each reader / writer. Then, this interval time slot value is stored. Note that “1” added here is a unit time of the time slot value.

  In this example, a plurality of reader / writers are taken as an example, but each time throttle value may be set for each frequency band.

  FIG. 7 is a diagram showing a flowchart when the central control apparatus transmits a reader / writer read command to the reader / writer or receives reader / writer response data using the schedule data of FIG. 6 with one reader / writer. This control process is performed for a plurality of reader / writers. In step S700, when the central control apparatus receives a process start command from an external communication apparatus connected to the host interface, or sets a process start condition in advance and performs the process when the condition is met. Start. 0 is substituted into the time slot T, and the process proceeds to step S701. In step S701, the time slot T is compared with the set start time slot T1. If the values do not match, the process proceeds to step S702. If the values are the same, the process proceeds to step S703. In step S702, 1 is added to the time slot T, and the process proceeds to step S701.

  On the other hand, in step S703, communication with the reader / writer is performed. In this example, a reader / writer read command is transmitted to the reader / writer, reader / writer response data is received, and RFID tag reading processing is performed. At this time, the reader / writer receives the reader / writer read command, performs the processing of the flowchart shown in FIG. 5, and transmits the result to the central control apparatus as reader / writer response data. When the RFID tag reading process ends, the process proceeds to step S704. In step S704, 0 is substituted for time slot T, and the flow advances to step S705. In step S705, the time slot T is compared with the set interval time slot T2. If the values match, the process proceeds to step S703 and the process is repeated. On the other hand, if the values do not match, the process proceeds to step S706. In step S706, 1 is added to the time slot T, and the process proceeds to step S705 to repeat the process. Although the end is not shown in the figure, as in the case of the start, when the central control device receives a processing end command from the external communication device connected to the host interface, or sets the processing end condition in advance In addition, the process ends when the condition is met.

  Next, the operation when the central control apparatus controls the three reader / writers using the same frequency band in the processing described in FIGS. 6 and 7 will be described.

  FIG. 8 shows an example of execution when the reading process is individually repeated by three reader / writers using the same frequency band without using the functions described in FIG. 6 and FIG. FIG. The number of frequency bands that can be used by the reader / writer is limited, and two or more frequency bands cannot be used simultaneously. Therefore, even if three reader / writers try to execute the reading process at the same time using the same frequency band, only one of them can execute the reading process, while the remaining two units cannot execute the reading process.

  FIG. 8 shows reading processing of the reader / writer 1_610, the reader / writer 2_620, and the reader / writer_630 when the time slot 602 is from 1 to 10. In FIG. 8, first, the reader / writer 1_610 performs a reading process 611. Meanwhile, the reader / writer 2_620 and the reader / writer 3_630 cannot execute the reading process. When the reading process 611 of the reader / writer 1_610 is completed, the reading process 621 of the reader / writer 2_620 starts. Similarly to the above, the reader / writer 1_610 and the reader / writer 3_630 cannot execute the reading process during this period. When the reading process 621 of the reader / writer 2_620 is completed, the reading process 612 of the reader / writer 1_610 is executed. Thereafter, similarly, when the reading process 612 of the reader / writer 1_610 is completed, the reading process 631 of the reader / writer 3_630 is executed, the reading process 613 of the reader / writer 1_610 is executed, the reading process 622 of the reader / writer 2_620 is executed, and the reader / writer 1_610 Reading processing 614 is executed, and reading processing 623 of the reader / writer 2_620 is executed.

  As a result, the reader / writer 1_610 performs reading processing four times, the reader / writer 2 performs three times, and the reader / writer 3 performs one time. In particular, the reader / writer 3_630 performs almost no reading processing. In the case of this example, since the reading process is started when the three reader / writers individually use the available frequency band, the number of readings and timing of the three readers / writers are not constant. Depending on the case, the reader / writer 3_630 may have the largest number of reading processes, and all three units may have the same number of times. There is a great possibility that the number of times the reading process can be performed becomes unstable, and the system does not function normally. In addition, the reading processing time is not constant depending on the setting of the reader / writer, the number of RFID tags to be communicated, the surrounding environment, and the like, which may cause the system not to function normally.

  FIG. 9 is a diagram illustrating an execution example of the reading process when the functions of FIGS. 6 and 7 are used in the centralized control apparatus and three reader / writers are controlled simultaneously. Reader / writer 1_610 has a start time slot of 1 and interval time slot of 4, reader / writer 2620 has a start time slot of 3 and interval time slot of 4, reader / writer 3_630 has a start time slot of 4 and interval time slot Is set to 4.

  The reader / writer 1_610 executes the reading process 641 when the time slot is 1. Next, when the time slot is 3, the reader / writer 2_620 executes the reading process 651. Next, when the time slot is 4, the reader / writer 3_630 executes the reading process 661. Next, when the time slot is 5, the reader / writer 1_610 executes the reading process 642. Next, when the time slot is 7, the reader / writer 2_620 executes the reading process 652. Next, when the time slot is 8, the reader / writer 3_630 executes the reading process 662. Next, when the time slot is 9, the reader / writer 1_610 executes the reading process 643. Unlike the operation described with reference to FIG. 8, the timing at which each reader / writer executes a reading process is defined in advance, so that the RFID tag system operates normally and constantly. It is desirable to set the start time slot and the interval time slot in consideration of the difference in the reading processing time depending on the number of RFID tags to be communicated and the number of reader / writers to be controlled simultaneously. For example, the registration method shown in FIG. 6 is used.

  In addition, it is apparent from the comparison between FIG. 9 and FIG. 8 that when FIG. 9 is used, that is, the present embodiment enables efficient operation as a whole compared to the conventional case, that is, FIG. is there. For example, the reading of “631” in FIG. 8 corresponds to the reading of “661” in FIG. 9, and the time slot values “5” and “4” are applied to FIG. In this case, reading can be performed faster. Initially, FIG. 8 “621” = time slot value “2” and FIG. 9 “651” = time slot value = “3”, which is slower than the present embodiment. ) Read can be executed.

  Next, when a process at an arbitrary timing is interrupted while a plurality of reader / writers repeat the reading process in the process described with reference to FIG. 9, interrupt processing is ensured while maintaining the accuracy of the RFID tag system. A method to be executed will be described.

  FIG. 10 shows a case where the central control apparatus repeats the process of transmitting the reader / writer command data to the reader / writer or receiving the reader / writer response data using the schedule data of FIG. 6 with one reader / writer. It is the figure which showed the flowchart of the process for coping with the case where there is a possibility of the interruption process of.

  Here, as an example of the interrupt process, a write process for storing data in the memory of the RFID tag is used. Other examples of interrupt processing include locking and high priority processing. In step S710, when the central control apparatus receives a process start command from an external communication apparatus connected to the host interface, or sets a process start condition in advance and performs the process when the condition is met. Start, assign 0 to the time slot T, and go to step S711. In step S711, the time slot T is compared with the set start time slot T1. If the values do not match, the process proceeds to step S712. If the values are the same, the process proceeds to step S713. In step S712, 1 is added to the time slot T, and the process proceeds to step S711.

  On the other hand, in step S713, it is determined whether or not there is an interrupt process other than the read process between the start of step S710 and the start of the process in step S713. If there is no interrupt process, the process proceeds to step S714. If there is an interrupt process, the process proceeds to step S715. Here, if there is request information for another process from the user or the like, it is determined that there is an interrupt process.

  In addition to detecting the presence / absence, it may be determined whether the interrupted process has a higher priority than the reading process, and the process may proceed to step S714 or S715 based on the result. That is, the priority indicating the priority for each type of processing is determined using the priority table. In this case, if the priority of the reading process is higher than the process requested by the request information, it is determined that there is an interrupt process, and if it is low, it is determined that there is no interrupt process. At this time, if it is determined that there is no interrupt processing, the process proceeds to step S714, and the request for the processing requested by the request information is not accepted. Alternatively, after the reading process is executed, when the reading process (or a predetermined number of reading processes) is completed, the process requested by the request information may be executed.

  In step S714, communication with the reader / writer is performed. In this example, a reader / writer read command is transmitted to the reader / writer, reader / writer response data is received, and RFID tag reading processing is executed. That is, the reading process is executed according to the schedule data. At this time, the reader / writer receives the reader / writer read command, performs the processing of the flowchart shown in FIG. 5, and transmits the result to the central control apparatus as reader / writer response data. In the process of communicating with the RFID tag in step S503 of the flowchart, the process related to the RFID tag read command is executed for the RFID tag. When the RFID tag reading process is completed, the process proceeds to step S716.

  On the other hand, in step S715, interrupt processing is executed. In this example, since the writing process is executed by interruption, the reader / writer write command is transmitted to the reader / writer, the reader / writer response data is received, and the RFID tag writing process is executed. At this time, the reader / writer receives the reader / writer write command, performs the processing of the flowchart shown in FIG. 5, and transmits the result to the central control apparatus as reader / writer response data. In the process of communicating with the RFID tag in step S503 of the flowchart, a process related to the RFID tag write command is executed for the RFID tag. When the RFID tag writing process is completed, the process proceeds to step S716. Here, the reading function specified in the schedule data is stopped and the accepted function is executed. Alternatively, it is possible to wait until the reading function defined by the scheduled function being executed when the request is received and to execute the received function before executing the next reading.

In step S716, 0 is substituted for time slot T, and the flow advances to step S717. In step S717, the time slot T is compared with the set interval time slot T2. If the values match, the process proceeds to step S713 to repeat the process. On the other hand, if the values do not match, the process proceeds to step S718. In step S718, 1 is added to the time slot T, the process proceeds to step S717, and the process is repeated. In step S713 after the second time, it is determined whether or not there is an interrupt process between the process in the previous step S713 and the process in this step S713. Although the end is not shown in the figure, as in the case of the start, when the central control device receives a processing end command from the external communication device connected to the host interface, or sets the processing end condition in advance In addition, the process ends when the condition is met.
Next, an operation when a write process is executed by interruption while the central control apparatus controls three reader / writers will be described.

  FIG. 11 is a diagram showing an operation when a write process is executed by an interrupt in the process of the flowchart described in FIG. 7 in the read process of the three reader / writers described in FIG. Reader / writer 1_610 has a start time slot of 1 and interval time slot of 4, reader / writer 2620 has a start time slot of 3 and interval time slot of 4, reader / writer 3_630 has a start time slot of 4 and interval time slot Is set to 4. The reader / writer 1_610 executes the reading process 641 when the time slot is 1. Next, when the time slot is 3, the reading process 651 of the reader / writer 2_620 is executed. Here, interrupt processing 671 is interrupted. Since the interrupt process 671 is executed at this timing, the read process 661 of the reader / writer 3_630 cannot be executed. Further, the reading process 642 of the reader / writer 1_610 cannot be executed. In this example, the interrupt process 671 executes a write process. Next, when the time slot is 7, the reader / writer 2_620 executes the reading process 652. Next, when the time slot is 8, the reader / writer 3_630 executes the reading process 662. Next, when the time slot is 9, the reader / writer 1_610 executes the reading process 643. If there is no interrupt processing, as in FIG. 9, the system operates consistently and normally. However, since interrupt processing has entered the reader / writer 1_610, the processing of the reader / writer 2_620 and the reader / writer 3_661 cannot be performed once. As a result, processing of other reader / writers is affected, and the RFDI tag system does not function normally.

FIG. 12 is a diagram showing an operation when a write process is executed by an interrupt using the process of the flowchart described in FIG. 10 for the read process of the three reader / writers described in FIG.
Reader / writer 1_610 has a start time slot of 1 and interval time slot of 4, reader / writer 2620 has a start time slot of 3 and interval time slot of 4, reader / writer 3_630 has a start time slot of 4 and interval time slot Is set to 4. The reader / writer 1_610 executes the reading process 641 when the time slot is 1 and the time slot is 1. Next, when the time slot is 3, the reading process 651 of the reader / writer 2_620 is executed. Next, interrupt processing 671 is inserted here, but is not immediately executed at this timing, and interrupt processing 671 is executed when the next reading processing timing, that is, when the time slot is 5. Therefore, the processing of other reader / writers is not affected as shown in FIG. Next, when the time slot is 4, the reading process 661 of the reader / writer 3_630 is executed.

  Next, the interrupt processing 672 that was interrupted earlier at time slot 5 is executed at this timing. Since there is an interrupt process 672, the original read process is not executed at this timing. Next, when the time slot is 7, the reader / writer 2_620 executes the reading process 652. Next, when the time slot is 8, the reader / writer 3_630 executes the reading process 662. Next, when the time slot is 9, the reader / writer 1_610 executes the reading process 643.

  According to the present embodiment, in an RFID tag system having a plurality of reader / writers, while the reader / writer performs a reading process, while maintaining the accuracy of the RFID tag system, it is possible to write, lock, and prioritize at an arbitrary timing. Can be reliably executed.

It is the figure which showed the structure of the information recording medium RFID tag, external communication apparatus reader / writer, and centralized control apparatus regarding one embodiment of this invention. It is the figure which showed the internal structure of the information recording medium RFID tag. It is the figure which showed the internal structure of the external communication apparatus reader / writer. It is the figure which showed the internal structure of the centralized control apparatus. It is the figure which showed the process sequence of the external communication apparatus reader / writer for communicating with an information recording medium RFID tag. This is schedule data at a timing when the centralized control device transmits a reader / writer command to the external communication device reader / writer. It is the figure which showed the process sequence at the time of a centralized control apparatus communicating with an external communication apparatus reader / writer. It is the figure which showed the example when three external communication apparatus reader / writers performed the reading process separately. It is the figure which showed the process when a centralized control apparatus controls the three external communication apparatus reader / writers, and performed the reading process. FIG. 10 is a diagram illustrating a processing procedure corresponding to an interrupt process when the central control apparatus controls three external communication device reader / writers to perform a read process. It is the figure which showed the process when the interruption process was inserted when the centralized control apparatus controlled the three external communication apparatus reader / writers and was performing the reading process. FIG. 11 is a diagram showing a process when an interrupt process is inserted when the central control apparatus controls three external communication device readers / writers and executes a read process using the processing procedure shown in FIG. 10. is there.

Explanation of symbols

100 RFID tag, 101 antenna, 102 rectification unit, 103 power supply unit, 104 communication control unit, 105 control unit, 106 storage unit, 110 RFID tag,
200 reader / writer, 201 reader / writer main body, 202 reader / writer antenna, 203 transmission / reception unit, 204 communication control unit, 205 control unit, 206 power supply unit, 207 host interface, 210 reader / writer,
300 RFID tag command data, 301 RFID tag response data, 302 reader / writer command data, 303 reader / writer response data,
400 centralized control device, 401 reader / writer connection interface, 402 host interface, 403 control unit, 404 power supply unit, 405 storage unit,

Claims (6)

In a wireless communication system including an external communication device that performs wireless communication with an information storage medium,
Means for storing schedule data for prescribing schedules for performing the functions in the wireless communication so as not to overlap in time;
Means for controlling wireless communication with the information storage medium in the external communication device so that the functions do not overlap in time according to the schedule data ;
A plurality of external communication devices that execute read processing for repeatedly reading information stored in the information storage medium in the same frequency band as wireless communication with the information storage medium,
Storage control means for storing the read processing start time and interval time of each of the plurality of external communication devices as the schedule data in the storage means,
Means for receiving request information for requesting execution of a function other than that stored in the means for storing;
Means for determining whether to perform interrupt processing for the function indicated by the received request information,
The means for controlling controls wireless communication in accordance with the contents of the judgment by the means for judging,
The means for determining determines whether the request information has been received when it is detected that the start time has been reached and when the interval time has elapsed, and when the request information is received, the request information indicates A wireless communication system , characterized in that a function is determined to be interrupted . The wireless communication system according to claim 1, wherein
The wireless communication system, wherein the information storage medium is an RFID tag. In the radio | wireless communications system in any one of Claim 1 or 2 ,
The storage control means registers an interval time having the same value as an interval time of each of the plurality of external communication devices. The wireless communication system according to claim 3,
The storage control means
Identify the earliest start time to start reading earliest and the last start time to start reading latest among the start times,
The wireless communication system, wherein the earliest start time is subtracted from the last start time, and the unit time of the interval time is added to the value calculated by the subtraction to calculate the interval time of the same value. . The wireless communication system according to claim 1, wherein
The storing means stores, for each function type, a priority indicating the priority of processing of the function,
The determination means compares the priority of the function indicated by the request information with the priority of the function in which the schedule data is stored, and preferentially executes processing of the function having a higher priority as a result of the comparison. A wireless communication system, characterized by: The wireless communication system according to claim 1, wherein
As a wireless communication with the information storage medium, each comprising a plurality of external communication devices that execute a reading process of repeatedly reading information stored in the information storage medium in the same frequency band,
The storage means further comprises storage control means for storing, as the schedule data, an end time of the reading process and an interval time until the next reading start time of each of the plurality of external communication devices. Wireless communication system.

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