JP5306169B2 - Data transmission method and monitoring system - Google Patents

Description

  The present invention relates to a data transmission method using a transmission line, and relates to a technique that is effective when applied to data transmission in a monitoring system such as a disaster prevention system or a security system.

  A monitoring device (receiver) that is installed in buildings or factories, event venues, and receives detection signals from heat detectors, smoke detectors, gas leak detectors, etc., and monitors the occurrence of disasters such as fires. In a disaster prevention system equipped with the above, when a monitoring device (receiver) and a plurality of detectors are connected by a transmission line to transmit a detection signal, the length of the transmission line becomes very long. Therefore, it is desirable that the number of transmission lines for transmitting signals and power supply lines for supplying power are small.

  Therefore, a monitoring device is conventionally used as a data transmission method in a monitoring system as shown in FIG. 7 that receives a detection signal from a heat detector, smoke detector, gas leak detector, etc. and monitors the occurrence of a disaster such as a fire. A data transmission system has been put into practical use, in which a receiver and a plurality of terminals such as detectors and repeaters are connected by a transmission line composed of two transmission lines to transmit signals and supply power. ing.

  As an example of such a two-wire data transmission method, as disclosed in Patent Document 1, for example, binary signals “0” and “1” are converted into waveforms (pulses) shown in FIGS. 8B and 8C. A method is known in which these are connected together to generate a pulse train as shown in FIG.

  More specifically, the portion T in FIG. 8A is a transmission data area such as an address and a command transmitted from the monitoring device (receiver) to the terminal, and the portion R is a return data area from the terminal. is there. At the time of data return, the monitoring device (receiver) continuously outputs a signal representing “1” as shown in FIG. 8C, and the terminal is connected between the transmission lines during the period when the signal is lowered to the low level. To control whether or not current is passed through. In FIG. 8A, a hatched portion indicates a state in which a current flows between transmission lines. When the monitoring device (receiver) detects this state, “0”, “ 1 ″ data can be received.

JP-A-60-28341

  In recent years, the amount of information that the monitoring device (receiver) wants to collect from the terminal side has increased with the increase in the size of buildings, diversification of detectors, increase in the size of disaster prevention systems, and the enhancement of system functionality. Yes. However, in the data transmission method disclosed in Patent Document 1, the return data area R is configured with a small number of bits and has no expandability, so that only data that can be expressed with a small number of bits can be transmitted. Therefore, in the data transmission system of Patent Document 1, it is difficult to cope with an increase in the number and types of detectors and an increase in the size and functionality of the disaster prevention system. As a result, it is necessary to replace all monitoring devices (receivers) and terminals with new ones to increase the size and functionality of the disaster prevention system. It was.

  The present invention has been made paying attention to the problems as described above, and the object of the present invention is to support a new data transmission system while leaving a terminal that has been compatible with the conventional data transmission system. It is an object of the present invention to provide a data transmission method and a monitoring system capable of collecting data by adding a terminal and connecting to an existing transmission line.

In order to solve the above problems, the invention described in claim 1
A data transmission method in which a control device and a plurality of terminals are connected by a transmission line, and a pulse signal including a predetermined data string is transmitted.
The data string includes a mode area in which information indicating whether the data string is a data string for data collection or a data string for terminal control is inserted between a start bit and a stop bit, and an address for designating a terminal It has a structure in which a storage area, a command area containing information indicating the content of a command for the terminal, and a return data area containing return data are arranged,
When the stop bit can be replaced with an extension bit corresponding to a waveform different from the waveform representing the bit, and the stop bit is replaced with the extension bit, extension return data in which return data is inserted after the extension bit It is transmitted as a data string with an area added ,
The return data area and the extended return data area include areas in which a sub-start bit and a sub-stop bit are added by the terminal before and after the data in these areas .

The invention according to claim 4
A monitoring device and a plurality of terminals connected to a transmission line extending from the monitoring device, and comprising a predetermined data string between the monitoring device and the plurality of terminals via the transmission line A monitoring system configured to be able to transmit data by a pulse signal,
The data string includes a mode area in which information indicating whether the data string is a data string for data collection or a data string for terminal control is inserted between a start bit and a stop bit, and an address for designating a terminal It has a structure in which a storage area, a command area containing information indicating the content of a command for the terminal, and a return data area containing return data are arranged,
The stop bit can be replaced with an extension bit corresponding to a waveform different from the waveform representing the bit,
When the monitoring device replaces the stop bit with the extension bit, it transmits as a data string with an extension return data area in which return data is inserted after the extension bit ,
The return data area and the extended return data area include areas in which a sub-start bit and a sub-stop bit are added by the terminal before and after the data in these areas .

According to the first or fourth aspect of the present invention, since the stop bit can be replaced with the extension bit, the data string can be extended by providing the terminal with a function of discriminating the extension bit. . Since a return data area can be added to the data string having the extension bit, it becomes possible to send an amount of data that could not be sent by a conventional terminal, and the conventional data transmission method Data can be collected by adding a terminal compatible with a new data transmission method and connecting it to a transmission line while leaving a terminal compatible with the previous. Therefore, when it is desired to expand the scale of a monitoring system that has already been installed or to increase its functionality, it is possible to cope with partial refurbishment without having to replace the entire device and avoid an increase in cost. .
According to the first or fourth aspect of the present invention, the sub-start bit and the sub-stop bit are added by the terminal before and after the data in the return data area and the extended return data area. Can reliably detect that a terminal capable of responding to a data string including the data range and extension bits in the return data area and the extended return data area is responding.

The invention according to claim 2 is the data transmission system according to claim 1,
In the return data area and the extended return data area, the waveform is changed according to data returned by the terminal.

The invention according to claim 5 is the monitoring system according to claim 4 ,
The return data area and the extended return data area of the data string transmitted from the monitoring apparatus via a transmission path have a waveform changed according to data returned by the terminal.

According to the second or fifth aspect of the present invention, the waveform of the return data area and the extended return data area of the data string is changed according to the data returned by the terminal. The function of supplying power can be easily realized.

The invention according to claim 3 is the data transmission system according to claim 1 or 2 ,
The information stored in the mode area is represented by a first pulse waveform or a second pulse waveform having the same time length and different waveforms, and the stop bit is represented by the same waveform as the first pulse waveform, The extension bit is represented by the same waveform as the second pulse waveform.

The invention described in claim 6 is the monitoring system according to claim 4 or 5 ,
The information stored in the mode area is represented by a first pulse waveform or a second pulse waveform having the same time length and different waveforms, and the stop bit is represented by the same waveform as the first pulse waveform, The extension bit is represented by the same waveform as the second pulse waveform.

According to the invention described in claim 3 or claim 6 , since the waveform representing the information stored in the mode area and the waveform representing the stop bit and the extension bit can be shared, it is necessary to generate many types of waveforms. As a result, the burden on the control device or the monitoring device can be reduced and the time length of the unit waveform can be shortened and the data return speed can be increased by the amount of waveform types.

  According to the present invention, a terminal that supports a new data transmission method is added and connected to an existing transmission line while collecting the data while leaving a terminal that has been compatible with the conventional data transmission method. It is possible to realize a data transmission method and a monitoring system that can be used.

1 is a system configuration diagram showing an embodiment of a monitoring system to which a data transmission method according to the present invention is applied. It is explanatory drawing which shows the definition of the waveform which comprises the data sequence used for data transmission in the monitoring system of embodiment. It is explanatory drawing which shows the structural example of the data string used for the data transmission with respect to the conventional terminal in the monitoring system of embodiment. It is explanatory drawing which shows the structural example of the data sequence used for the data transmission with respect to the terminal of a new function in the monitoring system of embodiment. It is a flowchart which shows an example of the procedure of the data transmission process by the conventional terminal in the monitoring system of embodiment. It is a flowchart which shows an example of the procedure of the data transmission process by the terminal of the new function in the monitoring system of embodiment. It is a system block diagram which shows an example of the conventional monitoring system. It is explanatory drawing which shows the definition of the data string used for the data transmission in the conventional monitoring system, and the waveform which comprises it.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment when the present invention is applied to a fire monitoring system as an example. The fire monitoring system of this embodiment includes a receiver 10 as a control device or a monitoring device, relays 30A and 30B connected to the receiver 10 via a transmission line 20, and relays 30A and 30B. The heat sensors 41A and 41B, the smoke sensors 42A and 42B, and the smoke exhaust damper 43 connected to the In addition, some of the heat detectors 41A and 41B and the smoke detectors 42A and 42B are directly connected to the receiver 10 by the transmission line 20 without passing through the repeater 30.

  Although not clearly shown in FIG. 1, the transmission line 20 is configured by two transmission lines so that signals can be transmitted through the two transmission lines while power can be supplied. . In the present specification, devices connected to the receiver 10 as the monitoring device via the transmission line 20 so as to be able to transmit data are collectively referred to as a terminal. Therefore, not only the sensor but also the repeater is a terminal. Further, in the fire monitoring system, a push button type transmitter that is operated by a human to notify the occurrence of an abnormality may be connected to the transmission line 20. Moreover, as a terminal connected to the smoke-proof repeater, a door ejector, a fire-proof shutter, etc. can be handled.

  In FIG. 1, reference numeral 41A denotes a conventional heat detector, reference numeral 42A denotes a conventional smoke detector, and reference numeral 41B denotes data of the present invention. A new function heat sensor capable of extended transmission by the transmission method, and a reference sign 42B are new function smoke sensors capable of extended transmission. As shown in FIG. 1, in the fire monitoring system of the present embodiment, a conventional sensor and a new function sensor capable of extended transmission are connected to the transmission line 20, and old and new sensors are mixed. Is characterized in that data transmission is possible.

  Note that the receiver 10 in FIG. 1 is a receiver having a new function capable of extended transmission by the data transmission method of the present invention. Further, when the repeater 30 includes a sensor with a new function among the sensors connected to the repeater, the repeater 30B with a new function capable of extended transmission is used instead of the conventional repeater 30A. Is used.

  The receiver 10 stores the addresses of all the repeaters 30A, 30B and sensors (41A, 41B, 42A, 42B) connected to the transmission path 20 and the device type (old / old distinction) in an internal nonvolatile memory. A table in which information indicating (including) is stored is stored. The receiver 10 can transmit data (including control commands) to each terminal by polling or addressing using the addresses stored in this table.

  Next, data transmission to the conventional terminal (30A, 41A, 42A) by the receiver (monitoring device) 10 and data transmission to the new function terminal (30B, 41B, 42B) will be described in detail.

  3 and 4 show examples of the configuration of data strings used for data transmission in the monitoring system of the present embodiment, and FIG. 2 shows the definition of unit waveforms constituting the data strings of FIGS. In FIGS. 3 and 4, the waveform indicated by the dotted line indicates that bit data to be transmitted is not determined in advance, and “0” or “1” is input depending on the data to be transmitted or returned. The hatched waveform means that the data returned from the terminal side is “1”. The system for supplying power simultaneously with the return of data and the transmission of signals as described above via two transmission lines can be realized by a known technique such as the invention disclosed in the above-mentioned Patent Document 1, so the description will be given. Omitted.

  3 and 4 is basically output from the receiver 10. Among these, FIG. 3 is a data string used for data transmission with a conventional terminal, and FIG. 3A is used for the receiver 10 to collect terminal type information from each terminal. 3B is a data string used for collecting information to be monitored (referred to as analog data in this specification) such as the state of the terminal and the detected amount, and FIG. 3C. Is a data string used for the receiver 10 to send commands (commands) to each terminal for control.

  As shown in FIG. 3, the transmission data string used in the present embodiment is a head area A1 where a start bit serving as a start pulse is entered on the transmission line, and whether the data string is for data collection. Mode area A2 containing information indicating whether it is for terminal control, address area A3 containing an address which is identification information of the terminal, command area A4 containing information indicating the content of a command to the terminal, return It consists of a return data area A5 in which data enters, and a termination area A6 in which stop bits that become stop pulses enter on the transmission path.

  In the address area A3, an address and an error check parity bit are stored. The command area A4 stores a command code, a parity bit, and an instruction end bit indicating the end of the instruction. The return data area A5 stores a return start bit (sub start bit), data to be returned from the terminal to the receiver, a parity bit, and a return stop bit (sub stop bit).

  The waveform of the return data area A5 output from the receiver 10 is a repetition of “0” shown in FIG. 2B, and this waveform is hatched in FIGS. 3 and 4 according to the data returned by the terminal. It is configured to recognize the data output from the terminal when the receiver detects the change in the waveform by a direct or indirect method. The return return bit at the beginning and the return stop bit at the end of the return data area A5 are determined so that “1” is always output by the terminal. Therefore, the receiver can monitor these bits and treat them as a transmission error if it is not "1".

  Note that the return data area A5 may be omitted in the data string of FIG. 3C used to send a command (command) from the receiver 10 to the terminal. In this case, a return stop bit may be provided. The provision of the return data area A5 in the data sequence of FIG. 3C also has the advantage that the configuration is the same as the other data sequences, so that the processing procedure can be shared and the design can be facilitated. When the return data area A5 is omitted in the data string of FIG. 3C, transmission from the receiver to the terminal can be regarded as access by addressing. In this case, the information in the mode area A2 can be regarded as information indicating whether transmission from the receiver 10 is polling or addressing.

  4A shows a data string used by the receiver 10 to collect terminal type information from a new function terminal, and FIG. 4B shows a status of the new function terminal to the terminal. A data string used for collecting information to be monitored such as a detection amount and a detection amount is shown. The data string used for the receiver 10 to send a command (command) to the new function terminal for control is the same as the data string for the conventional terminal shown in FIG. Therefore, illustration and description are omitted.

  As shown in FIGS. 4A and 4B, the data sequence transmitted to the new function terminal is from the start area A1 where the start bit is entered to the return data area A5 where the return data is entered. FIG. 3A and FIG. 3B are the same as the data strings for the conventional terminal shown in FIGS. On the other hand, the waveform entering the termination area A6 is different from the waveform entering the termination area A6 of the data string for the conventional terminal. Specifically, the waveform (stop bit) of the termination region A6 in the data string for the conventional terminal is the same as the waveform “1” in FIG. 2A, but is transmitted to the terminal with the new function. The waveform entering the region A6 in the data string to be processed is the same as the waveform of “0” in FIG. 2B, which is different from FIG.

  For the new function terminal, the receiver 10 transmits an extension return data area A7 and a termination area A8 containing stop bits after the area A6 containing the waveform of FIG. 2B. It has become. The extended return data area A7 is similar to the return data area A5 in the data string for the conventional terminal, and includes a return start bit, data to be returned from the terminal to the receiver, a parity bit, and a return stop bit. Stored. The waveform of the stop bit entering the termination area A8 is the same waveform as the waveform of the stop bit entering the termination area A6 of the data string for the conventional terminal ("1" in FIG. 2A). Since a return start bit and a return stop bit are added to the beginning and the end of the return data area A5 and the extended return data area A7, the receiver 10 as the monitoring device has a range of data in the return data area and the extended return data area. In addition, it is possible to reliably detect that a terminal capable of handling a data string including extension bits is responding.

  As the return data stored in the extended return data area A7 of the data string including the type information collection command (FIG. 4A), for example, a code indicating “relay” as the type in the return data area A5 is stored. In this case, it is a code for distinguishing between “fire alarm repeater” and “smoke prevention repeater”. Similarly, when a code indicating “heat sensor” or “smoke sensor” is stored as a type in the return data area A5, and there are a plurality of sensors having different sensing methods and functions, a code for distinguishing them. Can be stored and returned.

  The new function terminal detects the data string output from the receiver 10 to the transmission line 20, and checks whether the waveform in the area A6 is a waveform as shown in FIG. ), And when the waveform in the area A6 is as shown in FIG. 2B, the waveform in the extended return data area A7 following the area A6. Execute the process to put the return data for. That is, the waveform shown in FIG. 2B in the area A6 functions as a data extension signal (extension bit) for a new function terminal.

  On the other hand, if the waveform in the area A6 is a waveform as shown in FIG. 2A, the data return process is terminated when the new function terminal detects the waveform. In the conventional terminal connected to the transmission line 20, whether the waveform in the area A6 is the waveform as shown in FIG. 2A or the waveform as shown in FIG. 3 (A) and (B) even if a data string as shown in FIGS. 4 (A) and 4 (B) is transmitted. The same operation is performed as when such a data string is transmitted. That is, no response is made to the areas A6 and A7.

  FIG. 5 shows a procedure of data transmission processing in a conventional terminal. The conventional terminal constantly monitors the signal on the transmission line. When a signal comes in, it is first determined whether or not it is a start bit (start pulse) (step S1). If it is determined that the bit is not a start bit (No), the process ends without performing any processing. If it is determined that the bit is a start bit (Yes), the mode is information collection by looking at the waveform of the mode area A2 in the next step S2. Determine whether or not.

  If it is determined in step S2 that the information collection mode is set (Yes), it is determined whether or not the address in the address area A3 matches the address assigned to itself (step S3). If it is determined that the address does not match (No), the process is terminated. If it is determined that the address matches (Yes), in step S4, the waveform of the command area A4 is seen and the command is transmitted to the terminal. It is determined whether the command is a command to collect analog information such as the machine status.

  If it is determined in step S4 that the information collection command is (Yes), processing for creating analog data to be returned (step S6) and processing for outputting the created return data (step S7) are performed, and the processing is terminated. Return to S1.

  On the other hand, if it is determined in step S4 that the data string received from the waveform in the command area A4 does not command collection of analog information (No), the process proceeds to step S10 to command collection of type information. Judge whether or not. If it is determined that the type information collection command is (Yes), a process of outputting return data (type code) is performed (step S12), the process is terminated, and the process returns to step S1.

  If it is determined in step S2 that the mode is not information collection (No) from the waveform of the mode area A2, the process proceeds to step S15 to determine whether or not the mode is terminal control. If it is determined that the terminal control is not performed (No), the processing is terminated as it is. If it is determined that the terminal control is performed (Yes), whether the address in the address area A3 matches the address assigned to itself. It is determined whether or not (step S16). If it is determined that the address does not match with its own address (No), the process is terminated, and if it is determined that it matches with its own address (Yes), the control command in the command area A4 is responded in the next step S17. Generates and outputs control signals inside the terminal. Then, the process (step S18) which outputs the received control command as return data is performed, a process is complete | finished, and it returns to step S1.

  FIG. 6 shows a procedure of data transmission processing in a new function terminal. The difference between the flowchart of FIG. 6 and the flowchart of FIG. 5 is that, in the flowchart of FIG. 6, whether or not there is an extension signal (extension pulse) in the data string after the return data output processing in step S7 of the flowchart of FIG. Is provided (step S8), and when there is an extension signal, a return data is further added and output (step S9), and the return data output in step S12 of the flowchart of FIG. After the process, a process for determining whether or not there is an extension signal after the return data area A5 of the data string (step S13) and a process for adding the return data and outputting it when there is an extension signal (step S14) ) Is provided. Other than that, it is the same as the processing of the flowchart of FIG.

  As described above, the new function terminal adds the return data to the function to determine whether or not there is an extension signal behind the return data area A5 of the data string and outputs the additional return data. On the other hand, when a conventional terminal does not have such a function, a conventional terminal and a new function terminal are mixedly connected to the same transmission line 20 In addition, any terminal can perform data transmission normally.

  In addition, since the conventional terminal and the terminal having the new function execute the above-described processing for data transmission from the receiver 10, the receiver 10 responds to the type information collection command from the terminal. If the address registered in the table in the receiver 10 and the information indicating the type of the terminal do not match the type information collected from the terminal via the transmission path 20, the connection is established. It is possible to detect that there is an error.

  Specifically, for example, when a conventional terminal is mistakenly connected to a location (address) to which a new function terminal is to be connected, the receiver 10 outputs a data string to which an extension signal is added. However, since the conventional terminal does not respond at all to the extended data area, the receiver 10 can detect that a terminal having a new function is not connected. Even if the terminal responds to the extended data area, if the returned type information is different from the data in the table held by itself, a connection error is detected. be able to.

  Note that the processing according to the flowcharts of FIGS. 5 and 6 in the new function terminal may be switched as necessary. In other words, during normal monitoring, data collection and control may be performed by transmitting the non-expandable data string shown in FIG. 3, and such a response is not possible in the system to which this embodiment is applied. It becomes possible.

  Although the invention made by the present inventor has been specifically described based on the embodiment, the present invention is not limited to the embodiment. For example, in the above embodiment, a system using a heat sensor and a smoke sensor as a sensor is shown. However, the fire sensor is not limited to these, and an ion fire sensor or heat and smoke can be simultaneously used. Various detectors such as a composite fire detector capable of detecting, a fire detector using a pyroelectric element, and the like may be connected to the transmission line. Further, the arrangement of the data string areas transmitted through the transmission path is not limited to that shown in FIGS. 3 and 4, and for example, the order of the address storage area and the mode area may be reversed.

  Furthermore, in the above-described embodiment, it has been described that it is effective when applied to a system in which a conventional terminal and a new function terminal are mixed. However, a conventional device is a low-function device, and a new function device is In other words, it is a highly functional device. That is, when a monitoring system is laid in a newly built building or the like, a system can be constructed by mixing low-function devices and high-function devices, thereby reducing the cost of the entire system. In addition, since new high-performance devices can work as old low-function devices, sensor manufacturers can continue to provide old low-function devices as products. There is an advantage that inventory can be reduced when migrating.

  In the above embodiment, the case where the return data area A5 is expanded in the data string to be transmitted has been described as an example. However, when the address area A3 is desired to be expanded, the same technique can be applied to expand the return data area A5. Is possible. As a result, a monitoring system in which more (for example, 256 or more) terminal devices are connected to one transmission line can be constructed.

  Further, in the above description, the case where the invention mainly made by the present inventor is applied to a fire monitoring system has been described as an example. However, the present invention further includes a gas leak detector for harmful gases such as CO as a detector. Widely used for data transmission between a control device and multiple terminal devices installed at relatively distant locations, as well as a disaster prevention system, a security system with a moving body detector, and other surveillance systems. be able to.

10 Receiver (monitoring device, control device)
20 Transmission path 30 Repeater 30A Conventional repeater 30B New function repeater 41 Heat sensor 41A Conventional heat sensor 41B New function heat sensor 42 Smoke sensor 42A Conventional smoke sensor 42B New function Smoke detector 43 Smoke exhaust damper

Claims (6)

A data transmission method in which a control device and a plurality of terminals are connected by a transmission line, and a pulse signal including a predetermined data string is transmitted.
The data string includes a mode area in which information indicating whether the data string is a data string for data collection or a data string for terminal control is inserted between a start bit and a stop bit, and an address for designating a terminal It has a structure in which a storage area, a command area containing information indicating the content of a command for the terminal, and a return data area containing return data are arranged,
When the stop bit can be replaced with an extension bit corresponding to a waveform different from the waveform representing the bit, and the stop bit is replaced with the extension bit, extension return data in which return data is inserted after the extension bit It is transmitted as a data string with an area added ,
The return data area and the extended return data area include an area to which a sub-start bit and a sub-stop bit are added by a terminal before and after the data in these areas. .   The data transmission method according to claim 1, wherein the return data area and the extended return data area are changed in waveform according to data returned by the terminal. The information stored in the mode area is represented by a first pulse waveform or a second pulse waveform having the same time length and different waveforms, and the stop bit is represented by the same waveform as the first pulse waveform, 3. The data transmission method according to claim 1, wherein the extension bit is represented by the same waveform as the second pulse waveform. A monitoring device and a plurality of terminals connected to a transmission line extending from the monitoring device, and comprising a predetermined data string between the monitoring device and the plurality of terminals via the transmission line A monitoring system configured to be able to transmit data by a pulse signal,
The data string includes a mode area in which information indicating whether the data string is a data string for data collection or a data string for terminal control is inserted between a start bit and a stop bit, and an address for designating a terminal It has a structure in which a storage area, a command area containing information indicating the content of a command for the terminal, and a return data area containing return data are arranged,
The stop bit can be replaced with an extension bit corresponding to a waveform different from the waveform representing the bit,
When the monitoring device replaces the stop bit with the extension bit, it transmits as a data string with an extension return data area in which return data is inserted after the extension bit ,
The monitoring system, wherein the return data area and the extended return data area include an area to which a sub-start bit and a sub-stop bit are added by a terminal before and after the data in these areas . Wherein the response data area and extended response data area of the data sequence to be transmitted through the transmission path from the monitoring device, according to claim 4, wherein a waveform is changed in accordance with the data to which the terminal sends back The monitoring system described in. The information stored in the mode area is represented by a first pulse waveform or a second pulse waveform having the same time length and different waveforms, and the stop bit is represented by the same waveform as the first pulse waveform, The monitoring system according to claim 4 or 5, wherein the extension bit is represented by the same waveform as the second pulse waveform.

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