JP5469140B2 - Wireless communication system - Google Patents

Description

  The present invention relates to a wireless communication system having a configuration in which a master station installed in a building and a plurality of slave stations communicate with each other, and more specifically, for grasping whether or not a power supply battery of each slave station has been replaced. The present invention relates to a suitable wireless communication system.

  Conventionally, as a well-known technique related to this type of wireless communication system, for example, the state of the monitoring target is wirelessly transmitted to a controller that manages the monitoring target, so that it is possible to easily manage the state change of the monitoring target that occurs when the battery is replaced. "Wireless status transmitter" (see Patent Document 1).

  The technology according to Patent Document 1 includes a sensor that detects a state of a monitoring target, a transmission station that is a slave station to which the sensor is connected and transmits state information of the monitoring target wirelessly, and wirelessly transmits from the transmission station. In a configuration of a wireless communication system comprising a receiving station that is a master station that receives status information of a monitored object, a transmitting station (slave station) operates on a battery (battery) and detects the voltage of this battery The battery detection circuit is configured to determine that the battery (battery) has been replaced when the detection voltage becomes 0 V or more after being detected by the battery detection circuit as monitored by the control unit.

Japanese Patent Laid-Open No. 10-334380

  In the technique according to Patent Document 1 described above, as a result of detecting the voltage of the battery (battery) by the battery detection circuit in the transmission station (slave station), the presence or absence of battery replacement is determined, and therefore the determination function itself is appropriately performed. However, if the number of transmitters installed in the building is large, not only will the configuration be complicated, but when all the batteries in each transmitter station are replaced, whether or not the batteries have been replaced in all transmitter stations. Since it is necessary to check the battery replacement signal transmitted from each transmitting station stored in the receiving station (parent station), it is time-consuming to determine the status of battery replacement. There is a problem that can not be.

  The present invention has been made to solve such problems, and the technical problem is that even if there are many slave stations that operate on batteries, the battery replacement status can be easily and accurately determined with a simple configuration. It is an object of the present invention to provide a wireless communication system that can make a determination.

In order to solve the above technical problem, the first means of the present invention comprises at least one master station and a plurality of slave stations installed in the same building and each having a wireless communication function. In a wireless communication system in which a plurality of slave stations each operate with a battery as a driving power source, the plurality of slave stations receive a predetermined operation and output a battery replacement signal indicating that the battery has been replaced. A control unit having a battery exchange signal output function for notifying to the master station, the master station receiving a predetermined display control and performing a visible light emission display, and a plurality of slave stations as the predetermined display control Control that turns on or blinks the light-emitting display unit when battery replacement signals are received from at least one and less than the total number, and turns off the light-emitting display unit when battery replacement signals are received from all of the plurality of slave stations And , Battery replacement signal, as the predetermined operation, ON operation of a switch provided to a plurality of slave stations, or removably according to any of the operations Shoyo of the mounted PC control of a plurality of slave stations The control unit in the plurality of slave stations is wirelessly connected to the communication interface of the parent station in order to transmit the measured value obtained by individually measuring the state quantity related to the utility bill in the building to the parent station. Connected to an external interface that allows a PC to be attached to the plurality of slave stations, and the master station receives a battery exchange signal transmitted from the plurality of slave stations, comprising a battery replacement history information storage means for updatable store hold for each battery replacement history information is characterized in that a referable by the personal computer, which is detachably attached to the external interface of the master station

The second means of the present invention comprises at least one master station and a plurality of slave stations each installed in the same building and each having a wireless communication function, wherein the plurality of slave stations are respectively In a wireless communication system operating with a battery as a driving power source, a master station receives a predetermined operation and outputs a battery replacement work start signal instructing the start of battery replacement work to notify a plurality of slave stations A plurality of slave stations are provided with a control unit having a replacement work start signal output function, and a plurality of slave stations receive a predetermined display control and perform a light emission display so as to be visible, and a battery replacement work start signal as a predetermined display control A control unit that turns on or flashes the light emitting display unit when receiving a signal, outputs a battery replacement signal indicating that the battery has been replaced after receiving a predetermined operation, and notifies the master station. with each, battery replacement The business start signal is output from the control unit in the master station as a predetermined operation in response to either an ON operation of a switch provided in the master station or a specific operation of a detachable personal computer. The control unit in the slave station is connected to the communication interface of the parent station by wireless communication in order to transmit the measurement value obtained by individually measuring the state quantity related to the utility bill in the building to the parent station, Connected to an external interface that allows PCs to be installed in each slave station, the master station receives battery replacement history information for each slave station each time it receives a battery replacement signal transmitted from multiple slave stations. The battery replacement history information is provided with storage means for storing and maintaining the data so that the battery replacement history information can be referred to by a personal computer detachably attached to the external interface of the master station .

According to the wireless communication system of the present invention , in addition to the basic function that can be confirmed by the master station by transmitting the measured values individually measured for the amount of state related to the utility bill in the building from the slave station, for driving in each slave station Because it has a function that allows you to check the status of battery replacement work as a power source by visual recognition on the display unit of the light emitting display unit and the connected PC connected to the master station and each slave station, even if there are many slave stations that operate on batteries, With a simple configuration, the status of battery replacement can be easily and accurately determined without leakage, and leakage of battery replacement work can be prevented.

1 is a schematic block diagram illustrating a basic configuration of a wireless communication system according to Embodiment 1 of the present invention. It is the flowchart which showed the operation | movement process accompanying the battery replacement work by the control part with which the main | base station of the radio | wireless communications system shown in FIG. 1 is equipped. It is the flowchart which showed the operation | movement process accompanying the battery replacement work by the control part with which the subunit | mobile_unit of the radio | wireless communications system shown in FIG. 1 is equipped. Table-type battery replacement history information stored in the battery replacement history information storage unit of the storage unit provided in the master station of the wireless communication system shown in FIG. 1 and displayed on the display screen of the personal computer attached to the master station FIG.

  Hereinafter, the wireless communication system of the present invention will be described in detail with reference to the accompanying drawings by way of examples.

  FIG. 1 is a schematic block diagram showing a basic configuration of a wireless communication system according to Embodiment 1 of the present invention. This radio communication system includes a radio station specification master station 3 installed in the same building, each having a radio communication function, and two radio apparatuses remotely disposed with respect to the master station 3 The slave stations 1 and 2 are configured so that each slave station 1 and 2 operates with batteries 1g and 2g as driving power sources.

Among these, the slave stations 1 and 2 have the same configuration, and specifically measure each of a plurality of state quantities related to utility costs such as power consumption, water usage, gas usage, etc. And a pulse input unit 1a, 2a for inputting a pulse signal output from the meter 4 with pulse transmission and a meter 4 with pulse transmission (which requires measurement of power consumption in this embodiment) It is possible to attach and detach the LEDs 1h and 2h as light-emitting display units that perform light-emitting display so as to be visible in response to predetermined display control, and the personal computer 5 that can input and output within the range of the integrated value of the measured power consumption. At the same time, an external interface (IF) 1b, 2b for turning on, blinking, or turning off the LEDs 1h, 2h during predetermined display control, and the antenna of the master station 3 described later via the antennas 1f, 2f. Based on the input pulse signal and wireless processing units 1d and 2d that enable wireless communication with 3f and detect a battery replacement work start signal from the master station 3 that will be described later when receiving the signal. Storage units 1e and 2e that store the integrated value of the calculated power consumption, switches 1i and 2i that are used for ON operation when the batteries 1g and 2g are replaced, these pulse input units 1a and 2a, an external interface ( IF) 1b, 2b, wireless processing units 1d, 2d, storage units 1e, 2e, and switches 1i, 2i are connected to the integrated values of the above-mentioned power consumption based on the pulse signals from the pulse input units 1a, 2a, respectively. The storage unit 1e, 2e stores (stores) the processing for calculating the battery, the output processing of the battery replacement signal indicating the battery replacement performed by turning on the switches 1i, 2i, and the integrated value of the power consumption. Control units 1c and 2c including LED control units 1ca and 2ca for performing processing and turning on or blinking or turning off LEDs 1h and 2h as predetermined display control via external interfaces (IF) 1b and 2b, respectively. Configured.

In addition, the master station 3 is capable of attaching and detaching the personal computer 5 with the LED 3h as a light emitting display unit that performs a light emitting display so as to be visible in response to predetermined display control, and lights or blinks the LED 3h during predetermined display control. Alternatively, the wireless communication between the external interface (IF) 3b for turning off the light and the antennas 1f and 2f of the slave stations 1 and 2 via the antenna 3f is enabled, and the slave station to be described later when receiving a signal. A wireless processing unit 3d that detects battery replacement signals from 1 and 2 and a battery replacement history information storage unit 3ea that stores battery replacement history information such as the replacement date and time of the batteries 1g and 2g in the slave stations 1 and 2; Remotely through a storage unit 3e for storing identification information of the slave stations 1 and 2, a switch 3i used for an ON operation at the start of replacement work of the batteries 1g and 2g in the slave stations 1 and 2, and a communication line schematically shown Communication interface (IF) 3a that transmits the integrated value of the power consumption stored in the storage units 1e and 2e of the slave stations 1 and 2 to the monitoring center connected to the communication station (IF) 3a, these communication interface (IF) 3a, and external interface (IF) 3b, wireless processing unit 3d, storage unit 3e, and switch 3i are connected to each other, and measured values ( integrated values of power consumption) by the above-described measuring means of the slave stations 1 and 2 from the communication interface (IF) 3a (Including the battery replacement signal), the battery replacement work start signal output process that is output when the switch 3i is turned ON, and the battery replacement signal that is transmitted when the batteries 1g and 2g of the slave stations 1 and 2 are replaced. Is received (stored) in the storage unit 3e so that the battery replacement history information for each of the slave stations 1 and 2 can be updated, and the external interface Configured to include a control unit 3c which includes an LED controller 3ca for lighting or blinking, or off the LED3h as the predetermined display control through the (IF) 3b.

  In addition, the personal computer 5 connected to the external interfaces 1b and 2b of the slave stations 1 and 2 integrates the power consumption calculated by the control units 1c and 2c based on the pulse signals from the pulse input units 1a and 2a. Although it can be used within the range of values, it is also possible to output a battery replacement signal according to the intended operation of the personal computer 5 other than when the switches 1i and 2i are turned on by setting the functions of the control units 1c and 2c. It is. The personal computer 5 connected to the external interface 3b of the master station 3 can refer to the battery replacement history information stored in the battery replacement history information storage unit 3ea of the storage unit 3e on the display screen. It is also possible to output a battery replacement work start signal according to a specific operation of the personal computer 5 other than when the switch 3i is turned on by setting the function for 3c. In any PC 5, it is possible to acquire the reception result stored in each station and display it on the display screen, or to set the continuous test mode, start time limit, transmission output strength, etc. In addition, in the slave stations 1 and 2, if the control units 1c and 2c are set to store the battery replacement history information in the storage units 1e and 2e, the battery replacement history information is displayed on the display screen. Can be referred to.

  FIG. 2 is a flowchart showing an operation process associated with the battery replacement work by the control unit 3c provided in the master station 3 of the wireless communication system described above. The operation process here is a mode in which it is possible to accurately grasp the replacement work of the batteries 1g and 2g of the slave stations 1 and 2 which are wireless communication partners on the master station 3 side.

  The operation process will be described in detail with reference to FIG. 2. Here, as a premise process, first, an operator informs the master station 3 of the start of replacement of the battery 1g of the slave station 1 (or the slave station 2 The same applies to the battery 2g), and the switch 1i (or the switch 2i) is turned ON as a predetermined operation, whereby the control unit 1c (or the control unit 2c) determines that the battery is replaced, and the wireless processing unit 1d and A battery replacement signal indicating the replacement of the battery 1g (or battery 2g) is output to the antenna 3f of the master station 3 via the antenna 1f (or the wireless processing unit 2d and the antenna 2f). However, the actual replacement of the battery 1g (or battery 2g) here is performed after the switch 1i (or switch 2i) is turned on.

  Therefore, the control unit 3c of the master station 3 determines whether or not there is a battery replacement signal based on whether or not a battery replacement signal is received via the antenna 3f and the wireless processing unit 3d (step S11). If there is no battery replacement signal as a result of this determination, the process returns and repeats the process before this determination (step S11). If there is a battery replacement signal, identification of the slave stations 1 and 2 stored in the storage unit 3e is performed. The slave station is identified with reference to the information (step S12), it is determined that the battery replacement of the slave station 1 (or the slave station 2) has started, and the table format in the battery replacement history information storage unit 3ea of the storage unit 3e After the battery replacement history information is rewritten at the time when the switch 1i of the slave station 1 (or the switch 2i of the slave station 2) is operated, the table rewrite process (step S13) is performed, and then the LED control unit 3ca performs LED control. As a signal (light emission display control signal), an LED lighting command signal based on the LED lighting command (step S14) is output, and the LED 3h is transmitted via the external interface (IF) 3b. To light. However, as the light emission display control, a blinking pattern can be applied in addition to lighting. As a result, the manager of the master station 3 can accurately visually confirm that the battery 1g of the slave station 1 (or the battery 2g of the slave station 2) has been replaced by turning on or blinking the LED 3h.

  Subsequently, the control unit 3c determines whether or not a battery replacement signal has been received from all the slave stations (both the slave stations 1 and 2) (step S15). As a result of this determination, if no battery replacement signal has been received from all the slave stations, the process returns to the determination before whether or not the first battery replacement signal is present (step S11) and the subsequent processing is repeated. If the battery replacement signal is received, the battery replacement history information in the table format in the battery replacement history information storage unit 3ea of the storage unit 3e for the slave station received subsequently is rewritten at the time when the switch is operated. Thereafter, the LED control unit 3ca outputs an LED turn-off command signal based on the LED turn-off command (step S16) as an LED control signal (light emission display control signal), and turns off the LED 3h via the external interface (IF) 3b. Exit. As a result, the manager of the master station 3 can accurately visually check that all the batteries of the slave station (the battery 1g of the slave station 1 and the battery 2g of the slave station 2) have been replaced by turning off the LED 3h. .

  That is, according to the operation processing mode shown in FIG. 2, in order to turn off the LED 3h of the master station 3, it is necessary to receive battery replacement signals from all the slave stations 1 and 2, and all the slave stations 1, 2 can be confirmed visually by turning off the LED 3h of the master station 3, so that the battery exchange leakage of the slave stations 1 and 2 can be prevented appropriately. In the operation process of FIG. 2, the case where the control units 1c and 2c of the slave stations 1 and 2c output the battery replacement signal by the ON operation of the switches 1i and 2i has been described as a premise process. It is also possible to set so that the battery replacement signal is output from the control units 1c and 2c by a specific operation of the personal computer 5 attached to the external interfaces (IF) 1b and 2b of the stations 1 and 2.

  In any case, according to the operation processing mode of FIG. 2, it is assumed that the control units 1c and 2c of the slave stations 1 and 2 have a battery replacement signal output function and output a battery replacement signal. When the battery replacement signal is received from at least one of the slave stations by the control unit 3c from less than the total number, the LED 3h is turned on or blinked, and when the battery replacement signal is received from the total number, the LED 3h is turned off. Therefore, it is possible to easily and accurately determine whether or not the batteries 1g and 2g are replaced with a simple configuration. In the master station 3, the battery exchange history information in the battery exchange history information storage unit 3ea of the storage unit 3e is updated when the battery exchange signal of the slave stations 1 and 2 is received. Battery replacement history information can be acquired and managed appropriately.

  FIG. 3 is a flowchart showing an operation process associated with battery replacement work by the control units 1c and 2c provided in the slave stations 1 and 2 of the above-described wireless communication system. The operation process here is a mode in which the replacement work of the batteries 1g and 2g can be accurately grasped on the side of the slave stations 1 and 2 by the replacement work start instruction from the master station 3 which is a wireless communication partner.

  The operation process will be described in detail with reference to FIG. 3. Here, as a premise process, the worker starts the replacement work of the batteries 1g and 2g of the slave stations 1 and 2 from the master station 3 in the slave station 1. 2 is instructed to perform an ON operation as a predetermined operation on the switch 3i, so that the control unit 3c determines that an instruction to start the battery replacement work is given, and the slave station 1 is connected via the wireless processing unit 3d and the antenna 3f. The battery replacement work start signal is output to the wireless processing unit 1d and the antenna 1f of the mobile station 2 and the wireless processing unit 2d and the antenna 2f of the slave station 2.

  Therefore, the control units 1c and 2c of the slave stations 1 and 2 determine whether or not a battery replacement work start signal has been received via the radio processing unit 1d and the antenna 1f and the radio processing unit 2d and the antenna 2f of the slave station 2. (Step S21) is performed. If the battery replacement work start signal is not received as a result of this determination, the process returns to and repeats the process before this determination (step S21), but the wireless processing unit 1d and the antenna 1f, the wireless processing unit 2d of the slave station 2, and If the battery replacement work start signal is received via the antenna 2f, the control units 1c and 2c are based on the LED blinking command (step S22) as LED control signals (light emission display control signals) by the LED control units 1ca and 2ca. An LED blinking signal is output to blink the LEDs 1h and 2h via the external interfaces (IF) 1b and 2b. However, as the light emission display control, a lighting pattern other than blinking can be applied. As a result, the managers of the slave stations 1 and 2 can accurately visually recognize how the batteries 1g and 2g should be replaced by the blinking or lighting of the LEDs 1h and 2h.

  Subsequently, the control units 1c and 2c of the slave stations 1 and 2 determine whether or not there is a predetermined SW operation (step S23) depending on whether or not a predetermined operation has been performed by the switches 1i and 2i. As a result of this determination, if the predetermined operation of the SW is not performed, the process returns and repeats the process before this determination (step S23), but if the predetermined operation of the SW is performed, the LED controllers 1ca and 2ca perform LED processing. As a control signal (light emission display control signal), an LED turn-off command signal based on the LED turn-off command (step S24) is output to turn off the LEDs 1h and 2h via the external interfaces (IF) 1b and 2b. In response to a battery replacement signal output command (step S25) for notifying the master station 3 of the completion of replacement of the batteries 2g and 2g, the battery replacement signal is transmitted via the wireless processing unit 1d, the antenna 1f, the wireless processing unit 2d, and the antenna 2f. And output to the antenna 3f of the base unit 3 to end the operation process. As a result, the managers of the slave stations 1 and 2 can accurately visually confirm that all the batteries 1g and 2g have been replaced by turning off the LEDs 1h and 2h.

  That is, according to the operation processing mode shown in FIG. 3, in order to turn off the LEDs 1h and 2h, the administrator of the slave stations 1 and 2 controls the switches 1i and 2i when the batteries 1g and 2g are replaced. Since it is necessary to output a battery replacement signal from the parts 1c and 2c, if there is a slave station that has not replaced the battery, it can be visually confirmed from the LEDs 1h and 2h. Can be prevented. In the operation process of FIG. 3, the case where the control unit 3c of the master station 3 outputs the battery replacement work start signal when the switch 3i is turned on has been described as a prerequisite process. It is also possible to set to output a battery replacement work start signal from the control unit 3c by a specific operation of the personal computer 5 attached to the interface (IF) 3b.

  In any case, according to the operation processing mode of FIG. 3, it is assumed that the control unit 3c of the master station 3 has a battery replacement work start signal output function and outputs a battery replacement work start signal. When the battery replacement work start signal is received by the control units 1c and 2c of No. 2, the LEDs 1h and 2h are blinked or turned on. Since light emission display control is performed to output a battery replacement signal indicating completion of replacement of 2g and notify the master station 3, it is possible to easily and accurately determine whether or not to replace the batteries 1g and 2g with a simple configuration. Can do. Further, as in the case of the operation process of FIG. 2, the master station 3 finally receives the battery exchange signal from the slave stations 1 and 2 and the battery exchange history in the battery exchange history information storage unit 3ea of the storage unit 3e. Since the information is updated, the master station 3 can acquire the battery replacement history information in the slave stations 1 and 2 and manage it appropriately.

  FIG. 4 shows a table-type battery replacement history stored in the battery replacement history information storage unit 3ea of the storage unit 3e provided in the parent station 3 and displayed on the display screen of the personal computer 5 attached to the parent station 3. It is the figure which illustrated information. Here, as a display screen of the personal computer 5, a state where the battery replacement history screen 5A is displayed by attaching the removable personal computer 5 to the external interface (IF) 3b of the master station 3 and performing a necessary operation is shown. Yes.

  In the battery replacement history screen 5A of FIG. 4, the slave station No. is displayed as the battery replacement status on a certain date (February 25, 2011). 5Aa indicates all the slave stations under the control of the master station 3, and whether or not the exchange signal reception 5Ab has received the battery exchange signal at the master station 3 after receiving the battery exchange work start signal at each slave station The success or failure (O, x) is shown, and the exchange date and time 5Ac shows the date and time (year, month, date and time: expressed in minutes) when the previous battery exchange signal was received at the master station 3. Incidentally, in FIG. 4, No. 1 described in the wireless communication system of the first embodiment. 1, no. Those of the slave stations other than the slave stations 1 and 2 corresponding to 2 are also displayed. If such a battery replacement history screen 5A is developed on the display screen of the personal computer 5 and the details of the battery replacement status are referred to, battery replacement leakage can be prevented and the battery replacement operation can be executed efficiently.

  In the wireless communication system according to the first embodiment described above, the configuration of the two slave stations 1 and 2 and the single parent station 3 has been described with reference to FIG. As shown in FIG. 4, it can be applied to a configuration with three or more slave stations and one master station 1, or a configuration with two or more master stations and three or more slave stations. However, since it can be applied if each slave station is associated with each master station under wireless communication management, it can be applied to the configuration according to the first embodiment shown in FIG. It is not limited.

1, 2 Slave station 3 Master station 1a, 2a Pulse input unit 1b, 2b, 3b External interface (IF)
1c, 2c, 3c control unit 1ca, 2ca, 3ca LED control unit 1d, 2d, 3d wireless processing unit 1e, 2e, 3e storage unit 1g, 2g battery 1h, 2h, 3h LED (light emitting display unit)
1i, 2i, 3i switch 3a Communication interface (IF)
3ea Battery replacement history information storage unit 4 Meter with pulse transmission 5 Personal computer 5A Battery replacement history screen

Claims (2)

It is configured to include at least one master station and a plurality of slave stations each installed in the same building and having a wireless communication function, and each of the plurality of slave stations is operated by a battery as a driving power source. In a wireless communication system,
Each of the plurality of slave stations includes a control unit having a battery replacement signal output function for receiving a predetermined operation and outputting a battery replacement signal indicating that the battery is replaced to notify the master station,
The master station receives a predetermined display control and displays a light-emitting display so that it can be visually recognized. As the predetermined display control, at least one of the plurality of slave stations and less than the total number of the batteries When the exchange signal is received, the light-emitting display unit is turned on or blinked, and when the battery exchange signal is received from all of the plurality of slave stations, the control unit that turns off the light-emitting display unit ,
The battery replacement signal is generated by the plurality of slaves according to either the ON operation of a switch provided in the plurality of slave stations or the operation of a personal computer that is detachably attached as the predetermined operation. Output from the control unit in the station,
The control unit in the plurality of slave stations is connected to a communication interface of the parent station by wireless communication in order to transmit a measurement value obtained by individually measuring a state quantity related to a utility bill in the building to the parent station And connected to an external interface that allows PCs to be attached to the plurality of slave stations,
Each time the master station receives the battery replacement signal transmitted from the plurality of slave stations, the master station includes storage means for storing and holding battery replacement history information for each of the plurality of slave stations in an updatable manner. The exchange history information can be referred to by a personal computer detachably attached to the external interface of the master station . It is configured to include at least one master station and a plurality of slave stations each installed in the same building and having a wireless communication function, and each of the plurality of slave stations is operated by a battery as a driving power source. In a wireless communication system,
The master station receives a predetermined operation, outputs a battery replacement work start signal for instructing start of the battery replacement work, and has a control unit having a battery replacement work start signal output function for notifying the plurality of slave stations Prepared,
The plurality of slave stations turn on the light-emitting display unit when receiving the battery replacement work start signal as the predetermined display control, and a light-emitting display unit that performs light-emitting display so as to be visible under a predetermined display control. And a control unit that outputs a battery replacement signal indicating that the battery has been replaced and then notifies the master station by turning off the light emitting display unit in response to a predetermined operation and notifying the master station ,
The battery replacement work start signal is the control in the master station according to either the ON operation of a switch provided in the master station or a specific operation of a personal computer detachably attached as the predetermined operation. Output from the
The control unit in the plurality of slave stations is connected to a communication interface of the parent station by wireless communication in order to transmit a measurement value obtained by individually measuring a state quantity related to a utility bill in the building to the parent station And connected to an external interface that allows PCs to be attached to the plurality of slave stations,
Each time the master station receives the battery replacement signal transmitted from the plurality of slave stations, the master station includes storage means for storing and holding battery replacement history information for each of the plurality of slave stations in an updatable manner. The exchange history information can be referred to by a personal computer detachably attached to the external interface of the master station .

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