CN112349114B - Traffic early warning system for signal lamp-free plane intersection and wireless communication device thereof - Google Patents

Traffic early warning system for signal lamp-free plane intersection and wireless communication device thereof Download PDF

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CN112349114B
CN112349114B CN202011150259.6A CN202011150259A CN112349114B CN 112349114 B CN112349114 B CN 112349114B CN 202011150259 A CN202011150259 A CN 202011150259A CN 112349114 B CN112349114 B CN 112349114B
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packet
slave
data
early warning
data packet
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CN112349114A (en
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杨文臣
房锐
苏宇
胡澄宇
田毕江
李亚军
岳松
李薇
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BROADVISION ENGINEERING CONSULTANTS
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    • GPHYSICS
    • G08SIGNALLING
    • G08GTRAFFIC CONTROL SYSTEMS
    • G08G1/00Traffic control systems for road vehicles
    • G08G1/07Controlling traffic signals
    • G08G1/081Plural intersections under common control
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B31/00Predictive alarm systems characterised by extrapolation or other computation using updated historic data

Abstract

The invention relates to a traffic early warning system for a signal lamp-free plane intersection and a wireless communication device thereof, belonging to the technical field of traffic safety. The early warning system comprises N wireless communication devices, wherein one wireless communication device is used as a master control device, and the rest is used as slave devices; the master control equipment and the slave equipment communicate through the same wireless channel, and N is less than or equal to 8; the wireless communication device comprises a logic control module, a clock module, a 433MHz wireless module and a data input/output interface module; the invention only occupies a single channel for digital signal transmission, and the state of each device can be rapidly shared to other devices in all areas through a broadcasting mode. In order to avoid interference conflict when a plurality of devices adopt the same channel to transmit data, a time-sharing working protocol among the plurality of devices is designed, the total sharing of state data with a distance within 200 meters and a low delay time switching value among 8 devices is realized, and the method is easy to popularize and apply.

Description

Traffic early warning system for signal lamp-free plane intersection and wireless communication device thereof
Technical Field
The invention belongs to the technical field of traffic safety, and particularly relates to a traffic early warning system for a signal lamp-free plane intersection and a wireless communication device thereof.
Background
The intersections without signal control, especially the intersections with signal control, where the trunk roads and the branch roads are connected, are often sites with frequent traffic accidents. The dynamic early warning device is arranged at the relevant access position of the intersection, so that the accident occurrence probability can be effectively reduced.
However, these early warning devices must cooperate with each other to achieve an early warning effect, and such intersections often do not have good construction conditions, so that data needs to be exchanged in a wireless manner. The conventional wireless communication methods include a 4G network and a wireless local area network (WiFi), but for remote intersections, especially mountain intersections, the 4G communication network is difficult to ensure, and the WiFi communication distance cannot meet the communication needs between the early warning devices. Other conventional digital transmission technologies have the problem of point-to-point transmission or insufficient communication distance. Therefore, how to overcome the defects of the prior art is a problem to be solved in the technical field of traffic safety.
Disclosure of Invention
The invention aims to solve the defects of the prior art and provides a traffic early warning system for a signal lamp-free plane intersection and a wireless communication device thereof.
In order to realize the data exchange among the direction controllers, the invention adopts the following technical scheme:
a traffic early warning system for a signal lamp-free plane intersection comprises N wireless communication devices, wherein one wireless communication device is used as master control equipment, and the rest is slave equipment; the master control equipment and the slave equipment communicate through the same wireless channel, and N is less than or equal to 8;
the wireless communication device comprises a logic control module, a clock module, a 433MHz wireless module and a data input/output interface module;
the logic control module is respectively connected with the clock module, the 433MHz wireless module and the data input/output interface module and is used for setting the ID of the local machine, reading the time of the clock module, analyzing the data content of the data input/output interface and running a communication protocol to control the 433MHz wireless module to complete data communication;
the method comprises the steps that N wireless communication devices carry out periodic communication, each communication period is divided into N communication periods, each device respectively sends information in one communication period, and a main control device sends data in the first communication period;
the master control equipment continuously sends 2 timing data packets to all the slave equipment according to the self clock; the slave device corrects the clock according to the time interval of receiving the continuous timing data packet and keeps consistent with the clock of the master device;
the master control device sequentially sends out registration invitation packets to N-1 slave devices; when receiving the registration invitation packet, the slave device sends the registration packet to the master device, wherein the registration invitation packet is the same as the number of the slave device; the logic control module of the master control device is also used for deleting the wireless communication with the slave device which does not receive the registration packet;
the main control equipment is also used for sending a heartbeat signal packet to each slave equipment, and the heartbeat signal packet is used for generating time synchronization calibration information of the coordination equipment;
and each slave device generates a slave device data packet according to the state change of the vehicle detector and the early warning state change in the previous period and shares the data packet with each device of the early warning system.
Further, it is preferable that the master device continuously transmits 2 timing data packets to the slave device according to its own clock interval of 1 second.
Further, it is preferable that the adjacent two registration invitation packet times are 100 milliseconds.
Further, preferably, the heartbeat signal packet includes an information-free heartbeat data packet and an information-containing heartbeat data packet; when the sensor state and the early warning state change in the previous period, the generated heartbeat data packet is an information heartbeat data packet, otherwise, the generated heartbeat data packet is an information heartbeat data packet without information.
Further, preferably, if the logic control module of the slave device does not receive the heartbeat signal packet of the master device for a continuous period of time, the slave device in the next communication period of the master device is upgraded to the master device.
Further, preferably, if the logic control module of the slave device does not receive the heartbeat signal packet of the master device for 2000 consecutive communication periods, the slave device in the next communication period of the master device is upgraded to the master device.
Further, it is preferable that the timing packet, the registration invitation packet, the registration packet, the heartbeat packet, and the reset packet are each composed of 4 binary bytes, each having 8 bits.
Further, it is preferable that the slave device data packet includes a vehicle detection sensor state to which the device is connected, an early warning information display screen operating state, a vehicle detection sensor state change time, and a system state checksum of the current respective entry directions.
Further, preferably, once the master control device receives a data packet, the checksum of the master control device is different from the checksum of the master control device, the checksum exception handling process is started, a reset data packet is sent out, the data of each device is forced to be reset, and the communication cycle is restarted after the next heartbeat data packet.
The invention also provides the wireless communication device.
The information sent by any one device can be received by all devices at the same time, so that the system checksum is the sum of all the states of the devices received by the system checksum.
The application condition and layout characteristics of the traffic early warning system equipment of the signal-free equal-plane intersection mainly comprise:
1. the early warning system needs to arrange a set of no more than 4 vehicle detection sensors in each entrance direction of the intersection;
2. the early warning system needs to arrange an early warning information display screen in each entrance direction of the intersection;
3. the controllers in different directions receive and control the vehicle detector information and the early warning display screen state of the intersection;
4. the controllers in different directions need to exchange vehicle detection information and early warning display states;
5. during data exchange, data synchronization among the controllers is required, and the delay is less than 10 milliseconds;
6. the distance between the controllers in different directions is generally 100-200 meters;
7. typically the entrance direction at each intersection will not exceed 8.
Aiming at the characteristics of the traffic early warning system of the non-signal equal-plane intersection, the invention provides a wireless communication device among all early warning units, and the device has the following characteristics:
1. the data is shared among all devices, namely, the data of each device is shared in other real time;
2. the communication data quantity between the devices is not large, and is usually multi-bit switching value state data;
3. the communication distance between the devices can reach 200 meters;
4. the data communication delay between the devices is not more than 20 milliseconds;
5. full sharing of data between no more than 8 devices can be supported.
Compared with the prior art, the invention has the beneficial effects that:
the invention realizes the full sharing of the state data of the switching value of the low delay time with the distance of less than 200 meters between all the early warning equipment controllers in the directions of not more than 8 inlets in the traffic early warning system of the signal lamp-free plane intersection. The data exchange between the inlet direction devices can be carried out independently of surrounding infrastructure, so that the installation cost of the intersection traffic early warning system is greatly reduced; meanwhile, the wireless communication device provided by the invention uses lower cost to overcome the problems of insufficient transmission distance, high communication cost, poor communication instantaneity and the like in other wireless communication modes, and provides a low-cost and high-efficiency solution for data among multiple traffic early warning devices on a road.
Drawings
FIG. 1 is a block diagram of a wireless communication device of traffic warning equipment at a traffic intersection without signal lamps;
FIG. 2 is a block diagram of a data packet;
FIG. 3 is a communication time slice allocation diagram;
fig. 4 is a data transmission flow chart.
Detailed Description
The present invention will be described in further detail with reference to examples.
It will be appreciated by those skilled in the art that the following examples are illustrative of the present invention and should not be construed as limiting the scope of the invention. The specific techniques or conditions are not identified in the examples and are performed according to techniques or conditions described in the literature in this field or according to the product specifications. The materials or equipment used are conventional products available from commercial sources, not identified to the manufacturer.
A traffic early warning system for a signal lamp-free plane intersection comprises N wireless communication devices, wherein one wireless communication device is used as master control equipment, and the rest is slave equipment; the master control equipment and the slave equipment communicate through the same wireless channel, and N is less than or equal to 8;
as shown in fig. 1, the wireless communication device includes a logic control module, a clock module, a 433MHz wireless module, and a data input/output interface module;
the logic control module is respectively connected with the clock module, the 433MHz wireless module and the data input/output interface module and is used for setting the ID of the local machine, reading the time of the clock module, analyzing the data content of the data input/output interface and running a communication protocol to control the 433MHz wireless module to complete data communication;
the method comprises the steps that N wireless communication devices carry out periodic communication, each communication period is divided into N communication periods, each device respectively sends information in one communication period, and a main control device sends data in the first communication period;
the master control equipment continuously sends 2 timing data packets to all the slave equipment according to the self clock; the slave device corrects the clock according to the time interval of receiving the continuous timing data packet and keeps consistent with the clock of the master device;
the master control device sequentially sends out registration invitation packets to N-1 slave devices; when receiving the registration invitation packet, the slave device sends the registration packet to the master device, wherein the registration invitation packet is the same as the number of the slave device; the logic control module of the master control device is also used for deleting the wireless communication with the slave device which does not receive the registration packet;
the main control equipment is also used for sending a heartbeat signal packet to each slave equipment, and the heartbeat signal packet is used for generating time synchronization calibration information of the coordination equipment;
and each slave device generates a slave device data packet according to the state change of the vehicle detector and the early warning state change in the previous period and shares the data packet with each device of the early warning system.
Preferably, the master device continuously transmits 2 timing data packets to the slave device according to the own clock interval of 1 second.
Preferably, the two adjacent registration invitation packages are 100 milliseconds in time.
Preferably, the heartbeat signal packet comprises an information-free heartbeat data packet and an information-containing heartbeat data packet; when the sensor state and the early warning state change in the previous period, the generated heartbeat data packet is an information heartbeat data packet, otherwise, the generated heartbeat data packet is an information heartbeat data packet without information.
Preferably, if the logic control module of the slave device does not receive the heartbeat signal packet of the master device for a continuous period of time, the slave device in the next communication period of the master device is upgraded to the master device.
Preferably, if the logic control module of the slave device does not receive the heartbeat signal packet of the master device for 2000 consecutive communication periods, the slave device in the next communication period of the master device is upgraded to the master device.
Preferably, the timing data packet, the registration invitation packet, the registration packet, the heartbeat signal packet and the reset data packet are all composed of 4 binary bytes, and each byte has 8 bits.
Preferably, the slave device data packet comprises a vehicle detection sensor state, an early warning display working state, a sensor state change time and a system state checksum of the device.
The application condition and layout characteristics of the traffic early warning system equipment of the signal-free equal-plane intersection mainly comprise:
1. the early warning system needs to arrange a set of no more than 4 vehicle detection sensors in each entrance direction of the intersection;
2. the early warning system needs to arrange an early warning information display screen in each entrance direction of the intersection;
3. the controllers in different directions receive and control the vehicle detector information and the early warning display screen state of the intersection;
4. the controllers in different directions need to exchange vehicle detection information and early warning display states;
5. during data exchange, data synchronization among the controllers is required, and the delay is less than 10 milliseconds;
6. the distance between the controllers in different directions is generally 100-200 meters;
7. typically the entrance direction at each intersection will not exceed 8.
Preferably, once the master control device receives a data packet, the checksum of the master control device is different from the checksum of the master control device, the checksum exception handling process is started, a reset data packet is sent out, the data of each device is forced to be reset, and the communication period is restarted after the next heartbeat data packet.
Application instance
1. Basic definition
Device number: the equipment needing communication is required to have respective numbers in a number range of 0-7, and repeated equipment numbers cannot be obtained in each group of equipment;
the equipment monitors the working state: the device is in a state of receiving data;
the equipment transmits the working state: the device is in a state of transmitting data;
the equipment master control working state: a device state that generates a temporal heartbeat signal;
and the main control equipment: a device in a master control state;
a slave device: a device not in a master state;
transmission period: the time for a group of devices to complete one data broadcast in sequence;
and (3) data package: a packet consists of 4 binary bytes and is structured as shown in fig. 2. Wherein BYTE1 is BYTE1, D10 is BYTE1 lowest, and D17 is BYTE1 highest; BYTE2 is BYTE2, D20 is BYTE2 lowest, and D27 is BYTE2 highest; BYTE3 is BYTE3, D30 is BYTE3 lowest, D37 is BYTE3 highest; BYTE4 is the 4 th BYTE, D40 is the 4 th BYTE lowest bit, D47 is the 4 th BYTE highest bit; wherein: the D12D11D10 three-bit binary number represents the equipment number, and the value is from 000 to 111; the D16D15D14D13 four-bit binary number represents the packet type; d17 is a device type bit, 0 represents a master device, and 1 represents a slave device.
General description of working modes
The communication protocol operated by the wireless communication device supports wireless data communication among not more than 8 pieces of equipment, the same wireless channel is used in communication, and the communication transmission adopts a non-directional broadcasting mode. Each device performs broadcast communication in its own dedicated time slice. When N terminals share data, the protocol prescribes that N is less than or equal to 8, and the time slice allocation of each device is shown in figure 3. A communication cycle process is divided into N time slices, each device can only send data in the time slices which belong to the device, and can only receive data in the time slices which do not belong to the device. For example, the device 3 can only send out data during the time slice 3, and can only receive data at other times. In order to ensure the time synchronism of different devices, each time a certain period number (1000 periods are adopted in this example), the device with the smallest number (main control device) sends out a heartbeat signal for device time synchronism, all devices recognize the heartbeat signal, calibrate the self time and ensure the time synchronism of all devices. When the equipment does not need to synchronize data, the data does not need to be sent out even in the own time slices, so that the communication times are reduced, and the energy consumption is reduced. The entire data transmission process is shown in fig. 4.
Initialization protocol
The initialization protocol sets the initialization process of the wireless communication equipment and is controlled by the main control equipment. The device with the smallest protocol setting number is the master control device, and the other devices are the slave devices. The flow is shown in figure 4.
The initialization process comprises the following steps: the timing stage, the registration stage and the communication setting stage, the data protocol of each stage is set as follows.
) In the timing stage, the master control equipment continuously sends out 2 timing data packets according to the own clock interval of 1 second;
2) In the registration stage, the master control device sends out a registration invitation packet every 100 milliseconds, and 7 registration invitation packets are used for recording the registration packets sent out by the slave device. The slave device transmits a registration packet when the registration invitation packet is found to have the same number as the own device number.
) A communication setting stage: the main control equipment eliminates unregistered equipment, distributes communication time periods for each registered equipment, and continuously sends out setting packages of the equipment.
The setting of the 4 bytes 32 bit data of the timing data packet is as follows:
the numbers of the master control equipment which send out timing signals and are represented by three binary numbers of D10, D11 and D12 are from 000 to 111; D13D14D15D16 four-bit packet type value 1000; the device type bit d17=0 because of being a timing packet sent by the master control device; for example: the 32-bit number of the data packet is 0001 0000 0000 0000 0000 0000 0000, which represents a timing data packet sent by the No. 0 master control equipment;
the definition of the registration invitation package is as follows:
d10, D11, D12 three-bit binary numbers representing master device numbers; four-bit packet type values of D13, D14, D15 and D16 0100; the device type bit d17=0 because of being a registration invitation packet sent by the master device; d20, D21 and D22 are three-bit binary numbers, the number of the registration invitation packet is represented, the value is from 001 to 111, and the number equipment is corresponding to 1 to 7; for example: 32-bit data packet 0000 1000 1100 0000 0000 0000 0000 000, which represents master device No. 0, sends out registration invitation packet No. 3, and invites slave device No. 3 to register;
registration package is defined as follows
D10, D11 and D12 are three-bit binary numbers, the number of the expressed slave equipment is 001 to 111, and the numbers correspond to No. 1 to No. 7 equipment; d13, D14, D15, D16 four-bit packet type value 1100; the device type bit d17=1 due to being a registration packet issued by the slave device; for example: 1101 1001 0000 0000 0000 0000 0000 0000, which represents a registration packet issued by slave device No. 3;
the setup package is defined as follows:
d10, D11, D12 three-bit binary numbers representing master device numbers; d13, D14, D15, D16 four-bit packet type value 0010; the device type bit d17=0 because of being a set packet sent by the master device; d20, D21, D22 bits represent the slave device number that is set; d30, D31, D32 are time slice numbers used by the set slave devices; d40, D41, D42, D43 are each set time slice length, in 1ms. For example: 0000 0100 0100 0000 1000 0000 1000 0000, it is indicated that the master device No. 0 sets the device No. 2 to use time slices 1, each time slice being 1 millisecond in length.
Heartbeat signal protocol
The heartbeat signal protocol is a definition of a data packet sent by a master control device periodically, and is mainly used for inhibiting time dyssynchrony of each device caused by timing errors. In the process shown in fig. 3, the master control device sends out a heartbeat packet in the time slice 1 in fig. 3 every 1000 transmission periods.
The heartbeat signal packets are divided into two types, one is that the sensor state or the early warning state of the main control equipment is used when the sensor state or the early warning state does not change in the previous period, and the heartbeat signal packets are called as non-information heartbeat data packets; the other is that the sensor state or the early warning state of the master control equipment is used when the sensor state or the early warning state changes in the previous period, and the sensor state or the early warning state is called an information heartbeat data packet.
The non-information heartbeat packet is defined as follows:
d10, D11, D12 three-bit binary numbers representing master device numbers; the four-bit data packet type values of D13, D14, D15 and D16 are 0001; the device type bit d17=0 because of being a set packet sent by the master device;
the data packet with information heartbeat is defined as follows:
d10, D11, D12 three-bit binary numbers representing master device numbers; the four-bit data packet type values of D13, D14, D15 and D16 are 1001; the device type bit d17=0 because of being a set packet sent by the master device; bits D20 to D47 and 24 represent state change data of the master control equipment in the last communication period, and specific contents are found in a data protocol part;
5. data protocol
The data protocol defines the expression modes of the sensor state, the early warning working state, the sensor state change time and the system state checksum of the equipment in the data packet; the data protocol includes a slave device packet definition and a data with information heartbeat packet definition. The two data packets are different from each other only in BYTE1, and BYTE2, BYTE3 and BYTE4 are defined as the same. Defining a heartbeat signal protocol by using the information heartbeat data packet BYTE 1;
the slave device packet definition is as follows:
d10, D11, D12 three-bit binary numbers representing the device number from which the data is sent; the four-bit data packet type values of D13, D14, D15 and D16 are 1010; the device type bit d17=1 due to the set packet issued by the slave device; d23 d22D 21D 20, corresponding to the latest trigger states of the four vehicle detectors in the early warning device, 1 detecting the vehicle, 0 indicating that no vehicle is detected; d27 d26D 25D 24, representing the original trigger state of the four vehicle detectors of the device; d35 d34D 33D 32D 31D 30, which represents the earliest time at which a sensor state change occurs, and has a value of the number of milliseconds from the start time of the previous transmission period; d36 bit represents the latest early warning state, 1 represents early warning, and 0 represents no early warning; d37 bit indicates whether the early warning state changes in the previous transmission period, 1 indicates that the early warning state changes, and 0 indicates that the early warning state changes; the 8 bits of BYTE4 are the sum of all previously received BYTE2 values of the respective device packets, including BYTE2 in the packet.
Checksum exception handling protocol
Transmission errors may occur during the transmission of multiple devices, which may cause differences in the checksum of the device-to-device data packets. Once the master control device receives a data packet, the checksum of the master control device is different from the checksum of the master control device, the checksum exception handling process is started, a reset data packet is sent out, the data of each device is forced to be reset, and the communication period is restarted after the next heartbeat data packet.
The reset packet is defined as follows:
d10, D11, D12 three-bit binary numbers representing master device numbers; the four-bit data packet type values of D16, D15, D14 and D13 are 1111; the device type bit d17=0 because of being a set packet sent by the master device; other bits inactive;
7. heartbeat exception handling protocol
Failure of the master control device will cause the heartbeat signal to disappear, often resulting in loss of synchronization of the devices, so that the system cannot work. Thus, a heartbeat exception handling protocol is set. When no heartbeat signal is received in 2000 continuous transmission periods, the slave device using the time slice 1 is updated to the master device, a master switching data packet is sent out, and other devices enter the slave device interception working state. The new master device restarts the initialization procedure and starts a new transmission cycle.
The master switch packet is defined as follows
D10, D11, D12 three-bit binary numbers representing the new master device number; the four-bit data packet type values of D16, D15, D14 and D13 are 0000; the device type bit d17=0 because of being a data packet sent by the master control device; byte2=01010101, byte3=10101010, byte4=01010101.
The foregoing has shown and described the basic principles, principal features and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present invention, and various changes and modifications may be made without departing from the spirit and scope of the invention, which is defined in the appended claims. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (4)

1. The traffic early warning system for the signal lamp-free plane intersection is characterized by comprising N wireless communication devices, wherein one wireless communication device is used as master control equipment, and the rest is slave equipment; the master control equipment and the slave equipment communicate through the same wireless channel, and N is less than or equal to 8;
the wireless communication device comprises a logic control module, a clock module, a 433MHz wireless module and a data input/output interface module;
the logic control module is respectively connected with the clock module, the 433MHz wireless module and the data input/output interface module and is used for setting the ID of the local machine, reading the time of the clock module, analyzing the data content of the data input/output interface and running a communication protocol to control the 433MHz wireless module to complete data communication;
the method comprises the steps that N wireless communication devices carry out periodic communication, each communication period is divided into N communication periods, each device respectively sends information in one communication period, and a main control device sends data in the first communication period;
the master control equipment continuously sends 2 timing data packets to all the slave equipment according to the self clock; the slave device corrects the clock according to the time interval of receiving the continuous timing data packet and keeps consistent with the clock of the master device;
the master control device sequentially sends out registration invitation packets to N-1 slave devices; when receiving the registration invitation packet, the slave device sends the registration packet to the master device, wherein the registration invitation packet is the same as the number of the slave device; the logic control module of the master control device is also used for deleting the wireless communication with the slave device which does not receive the registration packet;
the main control equipment is also used for sending a heartbeat signal packet to each slave equipment, and the heartbeat signal packet is used for generating time synchronization calibration information of the coordination equipment;
each slave device generates a slave device data packet according to the state change of the vehicle detector and the early warning state change in the previous period, and shares the slave device data packet with each device of the early warning system;
the heartbeat signal packet comprises an information-free heartbeat data packet and an information-containing heartbeat data packet; when the sensor state and the early warning state change in the previous period, the generated heartbeat data packet is an information heartbeat data packet, otherwise, the generated heartbeat data packet is an information heartbeat data packet without information;
if the logic control module of the slave device does not receive the heartbeat signal packet of the master device all the time in 2000 continuous communication periods, the slave device in the next communication period of the master device is updated to the master device;
the slave device data packet comprises a vehicle detection sensor state, an early warning display working state, sensor state change time and a system state checksum of the device;
and once the master control equipment receives a data packet of the slave equipment, the checksum of the master control equipment is different from that of the slave equipment, a checksum exception processing process is started, a reset data packet is sent out, the data of each equipment is forced to be reset, and the communication period is restarted after the next heartbeat data packet.
2. The traffic early warning system for a signalless planar intersection of claim 1, wherein the master device continuously transmits 2 timing packets to the slave device according to its own clock interval of 1 second.
3. The signaleless planar intersection traffic warning system of claim 1, wherein two adjacent registration invitation packages are 100 milliseconds in time.
4. The traffic early warning system for a traffic signal-free planar intersection according to claim 1, wherein the timing data packet, the registration invitation packet, the registration packet, the heartbeat signal packet, and the reset data packet are each composed of 4 binary bytes, each byte having 8 bits.
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