CN109696869B

CN109696869B - Automobile central door lock control device and control method based on NFC (near field communication) technology

Info

Publication number: CN109696869B
Application number: CN201811650914.7A
Authority: CN
Inventors: 曾清德; 罗杰文; 陈智轩
Original assignee: Guangxi University of Science and Technology
Current assignee: Guangxi University of Science and Technology
Priority date: 2018-05-25
Filing date: 2018-12-31
Publication date: 2023-06-30
Anticipated expiration: 2038-12-31
Also published as: CN109696869A

Abstract

The control module comprises a microcontroller and a carrier transmission module, wherein the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiver transmitter (HSU); the carrier transmission module is used for identifying the ID of the card, and the microcontroller is used for comparing the ID identified by the carrier transmission module with the ID in the program, so that the comparison is correct, the on-off of the relay is conducted on the four-way relay board, and the state of the door lock motor or the ignition switch is controlled. The system has the advantages that the functions of enabling the traditional PKE to enter without keys, enabling the user to start with one key, enabling the vehicle to lock automatically after the user leaves the vehicle, enabling the vehicle to be electrified, enabling the engine to start and the like can be realized; the driver only needs to shake the smart phone slightly in front of the NFC induction area, the car door can be unlocked, the car is electrified, and the engine is started, so that a brand new safe, convenient and efficient wireless data interaction mode is provided for the car.

Description

Automobile central door lock control device and control method based on NFC (near field communication) technology

Technical Field

The invention relates to the technical field of automobile electronic control, in particular to an automobile central door lock control device and method based on NFC (near field communication) technology.

Background

At present, in the technical field of automobile electronic control, in particular to the control technology of an automobile central door lock, a mode of entering an automobile through a coded lock is generally adopted, the mode is safe and reliable, but a driver and a passenger need to carry a key with them to unlock the automobile central door lock to start the automobile, an object which needs to be carried with the driver and the passenger is added to a user, the key also needs to be lifted at any time to prevent losing, if the automobile is used by an automobile owner in a distant place, the driver and the automobile can safely enter and exit the automobile after waiting for taking a spare key once the key is lost or the key is locked in the automobile, and once a child is locked in the automobile by mistake, the key cannot be found to open the automobile door, and a great potential safety hazard exists.

Disclosure of Invention

The invention aims to provide an automobile central door lock control device and an automobile central door lock control method based on an NFC near field communication technology, wherein the automobile central door lock control device can control opening and closing of an automobile door lock and starting and stopping of an engine through the NFC NFC (Near Field Communication) technology, a driver can not need to carry an automobile key on the premise that the driver must carry a mobile phone to go out, and the NFC near field communication function on a mobile phone of a user is used for using a smart phone in the hand as the automobile key.

The solution of the invention is as follows:

the near field communication NFC (Near Field Communication) technology evolved from the radio frequency identification technology RFID (Radio Frequency Identification) and is a communication technology. NFC near field communication technology was developed by the company enzhi semiconductor NXP Semiconductors (original philips semiconductor), SONY of SONY and NOKIA. The technical basis is a radio frequency identification technology RFID and an interconnection technology thereof. NFC near field communication technology is a near field radio communication technology, and through the functions of integrated inductive reader/writer, inductive card and point-to-point pairing transmission on a single chip, specified target identification and related data exchange can be performed with compatible devices within a short distance through radio signals without establishing mechanical or optical connection between the compatible devices. The read operation of NFC near field communication technology adopts two modes, active read and passive read.

In recent years, NFC near field communication technology has been rapidly developed. The NFC chip and the antenna are mounted on the mobile phone, and the mobile phone can realize non-contact data interaction, such as small electronic payment, which is the basis of mobile payment. And the information of other NFC compatible devices or NFC cards and NFC tags can be conveniently read. The near-distance non-contact interaction of NFC near-field communication enables the whole authentication, identification and data exchange process to be simplified to a great extent, and the interactive access between electronic devices is safer and more efficient. NFC near field communication technology is now increasingly used. Through NFC technology, pairing can be established safely and rapidly between digital devices such as mobile phones, digital cameras and computers, and further wireless data interaction and information service are achieved. Through NFC technology, the mobile phone can also be used as electronic payment, a traffic all-purpose card, an access control key, an electronic boarding voucher and the like. This technology is currently widely used in various fields in japan and korea.

The NFC antenna is arranged at the automobile door handle, and the control device is arranged on the automobile to be matched with the NFC of the mobile phone, so that the mobile phone can be used as a remote control key. The device can realize traditional PKE keyless entry, one-key start, and the vehicle is automatically locked after a user leaves the vehicle. And the automobile remote control key does not need to be carried separately, so that the automobile remote control key is safe and convenient. The driver can unlock the vehicle door only by slightly shaking the smart phone in front of the NFC induction area. After entering the passenger room of the vehicle, the intelligent mobile phone is only placed in a specific induction area on the central console, so that the vehicle can be electrified and the engine can be started. Meanwhile, the device can be combined with the current popular wireless charging technology, and an induction charging plate is additionally arranged in an induction area, so that the electric quantity of the mobile phone is kept sufficient (the mobile phone is required to support the wireless charging function). The device provides a brand new wireless data interaction mode which is safer, more convenient and more efficient for automobiles.

Based on the characteristics of the technology, the specific technical scheme of the invention is as follows:

the automobile central door lock control device based on the NFC near field communication technology comprises mobile equipment carrying NFC functions, a control module and a four-way relay board, wherein the control module comprises a microcontroller and a carrier transmission module, and the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiver transmitter (HSU); the carrier transmission module is used for identifying the ID of the card, and the microcontroller is used for comparing the ID identified by the carrier transmission module with the ID in the program, so that the comparison is correct, the on-off of the 1-4 relays in the four-way relay board is controlled, and the state of the door lock motor or the ignition switch is controlled.

More specific technical schemes are as follows: the control module adopts two, four-way relay boards to adopt two, and every control module connects a four-way relay board, and one four-way relay board control door lock motor, and another four-way relay board control ignition switch's state.

Further: the control module adopts one, four-way relay board adopts two, and two four-way relay boards are connected respectively to control module's different pins, and in two four-way relay boards, one four-way relay board control door lock motor, the state of another four-way relay board control ignition switch.

Further: the microcontroller adopts an Arduino UNO Rev3 development board, and the carrier transmission module adopts a PN532 NFC board with an antenna, wherein: pins A4, A5, 2 and 3 of the microcontroller are correspondingly connected with pins MO/SDA/TX and NSS/SCL/RX, IRO, RST # of the carrier transmission module; the microcontroller uses Arduino language to communicate with the carrier transmission module by IIC protocol.

Further: pins 3.3V, GND, 4, 5, 6 and 7 of the microcontroller are correspondingly connected with pins V1, G1, S2, S3 and S4 of the four-way relay board.

Further: the microcontroller and the carrier transmission module are connected with the P70_IRQ pin, so that the carrier transmission module can quickly inform the microcontroller when a command exists.

Further: NFC antenna of carrier wave transmission module installs near front windshield or lock handle, and microcontroller and four-way relay board are installed in the hidden space of well accuse platform below.

A control method of an automobile central door lock control device based on NFC near field communication technology comprises the following steps:

the system building step: a mobile device carrying NFC function, a control module and a four-way relay board are adopted to form a system, wherein the control module comprises a microcontroller and a carrier transmission module, and the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiving and transmitting bus high-speed UART (HSU); the microcontroller employs an Arduino UNO Rev3 development board: the carrier transmission module adopts PN532 NFC board with antenna, wherein: pins A4, A5, 2 and 3 of the microcontroller are correspondingly connected with pins MO/SDA/TX and NSS/SCL/RX, IRO, RST # of the carrier transmission module; the microcontroller uses Arduino language to communicate with the carrier transmission module by adopting IIC protocol;

an interface setting step: the jumper wire of the main control interface of the adopted carrier transmission module is set as follows:

(1) A circuit connection step: the carrier transmission module and the microcontroller are connected according to the IIC protocol, and the connection method is as follows:

(2)

UNO board pin	PN532 board pin
		5V	5V
GND	GND
		A4	MO/SDA/TX
A5	NSS/SCL/RX
		2	IRO
3	RST#

The microcontroller and four-way relay board connection method is as follows:

UNO board pin	Relay board pin (High in)
		3.3V	V1
GND	G1
		4	S1
5	S2
		6	S3
7	S4

；

(3) The operation logic steps are as follows:

1) And a door lock control step: in order to realize the opening and closing functions of the door lock, the carrier wave transmission module recognizes the ID of the card and then compares the ID with the ID preset in the program, and the comparison result with the ID1 ID2 ID3 preset respectively controls the on-off of the 1-4 relays in the relay board 1, thereby controlling the state of the door lock motor;

2) An ignition control step: the carrier transmission module recognizes the ID of the card and then compares the ID with an ID4 preset in the program, and the comparison result controls the on-off of 4-8 relays in the relay board 2, thereby controlling the on-off of the vehicle power supply and the start-stop state of the engine.

3) The more specific technical scheme also comprises: in the door lock control step, the specific control method comprises the following steps:

setting an NFC card mode in the mobile phone, pre-storing card IDs required by executing each operation, clicking the function key in the mobile phone App when executing unlocking and locking operations, and starting card simulation by the NFC module of the mobile phone, wherein the mobile phone is close to a PN532 antenna of the device, the card IDs are successfully compared, and the device can execute corresponding operations according to the intention of an operator; if the card ID comparison fails, the vehicle gives out an audible and visual alarm;

1. Comparing the signals to meet the preset ID1, giving a high potential to the pin 4, sending the signals to the pin S1 of the relay board 1 through a connecting wire, enabling the relay 1 to be electrified and attracted, giving a low potential to the pin 4 after 2S, and releasing the power failure of the relay 1; the aim of this action is to provide power for the unlocking operation of the cabin door lock motor;

2. comparing the signals to meet the preset ID2, giving a high potential to the pin 5, sending the signals to the pin S2 of the relay board 1 through a connecting wire, enabling the relay 2 to be electrified and attracted, giving a low potential to the pin 5 after 2S, and releasing the power failure of the relay 2; the purpose of this action is to provide power to the latching operation of the cabin door lock motor;

3. comparing the signals to meet the preset ID3, giving a high potential to the pin 6, sending the signals to the pin S3 of the relay board 1 through a connecting wire, enabling the relay 3 to be electrified and attracted, giving a low potential to the pin 6 after 2S, and releasing the power failure of the relay 3; the aim of this action is to provide power for the unlocking operation of the motor of the trunk door lock;

4. when the card ID is not matched with the preset ID1 ID2 ID3 in the program, a high potential is given to the pin 7, a signal is sent to the pin S4 of the relay board 1 through a connecting wire, the relay 4 is electrified and closed, and after 2S, a low potential is given to the pin 7, and then the relay 4 is electrified and released; the purpose of this action is to provide power to the burglar alarm system, which causes the vehicle to emit an audible and visual alarm that may be illegally intruded by a person.

Further: in the door lock control step, the specific control method comprises the following steps:

the automobile ignition switch has four action positions of 0 OFF (LOCK), 1 ACC, 2 ON and 3 START; then introducing the functions of each action position one by one according to the two sequences of starting and stopping;

the starting sequence of the boarding (0-1-2-3-2):

when the ignition switch is placed at a 0 OFF (LOCK) position, only the position can pull out a car key, a steering wheel falls OFF a LOCK when the key is pulled out, the steering wheel is unlocked after the key is inserted, all electric appliances in the car are powered OFF, and the engine is stopped; the vehicle should be stopped for a long time or the driver needs to leave the vehicle to lock the vehicle;

when the ignition switch is arranged at the position of 1 ACC, partial electric appliances including instruments, lights, horns, windshield wipers, sound and 12V power supplies of a cigar lighter in the vehicle are electrified, the ECU power supply is powered off, the engine is stopped, a driver continues to use a comfort function on the vehicle when temporarily stopping, and the ignition switch can be arranged at the position of ACC according to the requirement; the electric appliances in the vehicle can cause the power shortage of the storage battery when the vehicle is used at the position for a long time, and the engine can not be started;

when the ignition switch is arranged at the position of 2 ON, all electric appliances in the vehicle are electrified, the electric appliances comprising the air conditioner ventilator are additionally electrified on the basis of ACC, the ECU is electrified and starts self-checking, the oil pump works to establish oil pressure, and the ignition system is also ready for starting; if the electric appliance in the vehicle is used at the position in the engine stop state for a long time, the battery is also deficient in power, and attention is paid;

When the ignition switch is placed at the 3 START position, the hand is required to keep the twisting force, and the 3 START position is self-reset to the 2 ON position; the 3 START position is on the basis of 2 ON positions, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started; the power of the electric appliance, which is originally powered on and comprises a 12V cigar lighter power supply, is cut off to ensure that the power supply of the starter is sufficient, and the engine can be started successfully;

after the engine is successfully started, the ignition switch is automatically reset to the position of 2 ON from the position of 3 START, the engine keeps running, the generator supplies power to all electric appliances on the automobile and charges a storage battery, namely the idle working condition of the automobile enters the preparation working condition before normal running;

the off-train stopping sequence (2-1-0):

when the ignition switch is arranged at the position of 2 ON, the engine keeps running, the generator supplies power to all electric appliances on the vehicle and charges a storage battery, and the vehicle is in an idle speed or running working condition;

when the ignition switch is arranged at the position of 1 ACC, the engine ignition system stops working, the engine is stopped, the ECU power supply is cut off, and partial electric appliances including an instrument, lamplight, a loudspeaker, a windshield wiper, a sound and a cigar lighter 12V power supply are electrified in the vehicle; the driver can temporarily park the vehicle for use with a comfortable function;

When the ignition switch is placed at a 0 OFF (LOCK) position, all electric appliances in the vehicle are powered OFF, the engine is stopped, the steering wheel falls OFF to LOCK when the key is pulled out, and four doors are automatically unlocked; the driver needs to lock the vehicle to leave the vehicle and should use the position;

the device realizes the substitution of the key ignition switch function:

comparing the signals to meet the preset ID4, giving a high potential to the pin 8, and sending the signals to the pin S1 of the relay board 2 through the connecting wire, so that the relay 5 is electrically attracted; the purpose of this action is to control steering wheel unlocking;

after time delay is 0.5s, a high potential is given to the pin 9, and the relay 6 is electrified to be attracted; the purpose of this action is to turn on the ACC circuit of the ignition switch; some electric appliances such as instruments, lights, horns, windshield wipers, sound equipment and cigarette lighter 12V power supply are electrified, the ECU power supply is powered off, and the engine is stopped;

after time delay for 1s, a high potential is given to the pin 10, and the relay 7 is electrified and closed; the purpose of this action is to turn ON the ON circuit of the ignition switch; all electric appliances in the vehicle are electrified, the electric appliances comprising an air conditioner ventilator are additionally electrified on the basis of ACC, the ECU is electrified and starts self-checking, the oil pump works to establish oil pressure, and the ignition system is also ready for starting;

after 2s of delay, a high potential is given to the pin 10, the relay 8 is electrified and closed, and after 3s of delay, a low potential is given to the pin 10, and then the relay 8 is electrified and released; the purpose of this action is to turn on the START circuit of the ignition switch; the 3 START position is on the basis of 2 ON positions, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started; the portion of the electrical appliance that originally was powered on, including the 12V cigar lighter power source, was powered off to ensure that the power supply of the starter was sufficient, and in total, that the engine could be successfully started.

The invention has the advantages that:

1. an NFC antenna is arranged at a handle of an automobile door, and a control device is arranged on the automobile to be matched with the NFC of the mobile phone, so that the mobile phone can be used as a remote control key; the device can realize traditional PKE keyless entry, one-key start, and the vehicle is automatically locked after a user leaves the vehicle. The automobile remote control key does not need to be carried separately, so that the automobile remote control key is safe and convenient; the driver can unlock the vehicle door only by slightly shaking the smart phone in front of the NFC induction area; after entering the passenger room of the vehicle, the intelligent mobile phone is only placed in a specific induction area on the central console, so that the vehicle can be electrified and the engine can be started; meanwhile, the device can be combined with the current popular wireless charging technology, and an induction charging plate is additionally arranged in an induction area, so that the electric quantity of the mobile phone is kept sufficient (the mobile phone is required to support the wireless charging function). The device provides a brand new wireless data interaction mode which is safer, more convenient and more efficient for the automobile;

2. NFC only needs to be in an open state and can easily help compatible equipment to pair and connect without any manual intervention, when a driver carries a mobile phone into a vehicle, bluetooth carried by a smart phone and a wireless local area network WLAN module can scan surrounding Bluetooth signals and WLAN signals, when Bluetooth and WLAN signals of a vehicle-mounted multimedia system are searched, the smart phone only needs to be close to a vehicle-mounted NFC induction identification area, and is paired with the vehicle-mounted NFC module through the NFC module on the smart phone, so that 13.56MHz short-distance wireless connection is established. The NFC module in the intelligent mobile phone is communicated with the vehicle-mounted NFC module, the access addresses of Bluetooth and WLAN of the vehicle-mounted multimedia system stored in an NFC data format are obtained by reading data in the vehicle-mounted NFC module, and then the pairing connection process of the Bluetooth and the WLAN is executed. The mobile phone is connected with the vehicle-mounted multimedia system quickly. This is called "pairing", and the pairing process is completed in less than 100 ms.

Drawings

Fig. 1 is a block diagram showing the construction principle of embodiment 1 of the control module of the present invention.

Fig. 2 is a block diagram showing the construction principle of embodiment 2 of the control module of the present invention.

Fig. 3 is a schematic circuit diagram of a control module according to embodiment 1 of the present invention using a carrier transmission module PN532 NFC board.

Fig. 4 is a schematic circuit diagram of a control module embodiment 1 of the present invention employing a microcontroller Arduino UNO Rev3 development board.

Fig. 5 is a schematic circuit diagram of a control module embodiment 1 of the present invention using a microcontroller Arduino UNO Rev3 development board.

Fig. 6 is a schematic circuit diagram of a central control device of the door lock of the present invention.

Fig. 7 is a schematic diagram of a mounting structure of the central control device.

Fig. 8 is a schematic view of a door handle NFC antenna mounting structure.

Detailed Description

The invention is further described in detail below with reference to the examples of the drawings:

the invention comprises mobile equipment carrying NFC function, a control module and a four-way relay board, wherein the control module comprises a microcontroller and a carrier transmission module, wherein the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiving and transmitting bus high-speed UART (HSU); the carrier transmission module is used for identifying the ID of the card, and the microcontroller is used for comparing the ID identified by the carrier transmission module with the ID in the program, so that the comparison is correct, the on-off of the 1-4 relays in the four-way relay board is controlled, and the state of the door lock motor or the ignition switch is controlled. Wherein: the microcontroller adopts an Arduino UNO Rev3 development board, and the carrier transmission module adopts a PN532 NFC board with an antenna.

As shown in fig. 4 and 5, the 1, 2, 3, 4, 5 and 6 ports in fig. 4 are connected with the 1, 2, 3, 4, 5 and 6 ports in fig. 5, so that a complete Arduino UNO Rev3 circuit diagram of the invention is formed. Arduino UNO Rev3 is a single chip development board based on Integrated Circuit (IC) ATmega328P, ATmega328P is a high-performance low-power-consumption AVR 8-bit microcontroller, and the last P is PicoPower, which is an energy-saving technology capable of reducing power consumption of chips. ATmega328P encapsulates the central processing unit CPU, CLOCK, memory array RAM based on advanced RISC architecture.

The PN532 NFC board is a highly integrated 13.56MHz carrier transmission module manufactured by Enzhi semiconductor company NXP Semiconductors (original Philips semiconductor).

Based on the basic technology described above, there are two embodiments of the present invention:

example 1:

as shown in FIG. 1, two identical modules are used to realize the door lock control and ignition control functions respectively, each module independently comprises a PN532 board shown in FIG. 3, an Arduino UNO board and a relay board which are formed by connecting ends of FIGS. 4 and 5 (after 1, 2, 3, 4, 5 and 6 are connected), a power supply supplies power to the two Arduino UNO boards respectively, and the two PN532 boards and the two relay boards are powered by the Arduino UNO board. PN532 responsible for door lock control uses antenna separation type, installs the antenna in the door handle alone, and the module responsible for ignition control uses antenna integral type, takes antenna circuit from the board.

Example 2:

as shown in fig. 2, unlike the first scheme, the second scheme does not control the start and stop of the vehicle engine using a separate PN532 plate and Arduino UNO plate, but shares the PN532 plate and Arduino UNO plate with the door lock control portion. Whether the door lock is controlled to open or close or the engine is started or stopped is identified from the same PN 532. The power supply supplies power to the Arduino UNO board independently, and the PN532 board and the two relay boards are powered by the Arduino UNO board. The PN532 board uses a dual-antenna version of an on-board self-contained antenna circuit plus an external antenna, the separate antenna is independently installed in a door handle, and an integrated antenna on the board is responsible for identifying ignition control signals.

The invention is described in detail below with reference to the embodiment shown in fig. 1:

the control module adopts two, four-way relay board adopts two, and every control module connects a four-way relay board, and one four-way relay board control door lock motor, the state of ignition switch is controlled to another four-way relay board.

The basic control method for the structure shown in fig. 1 is: the method comprises the following steps:

the system building step: a mobile device carrying NFC function, a control module and a four-way relay board are adopted to form a system, wherein the control module comprises a microcontroller and a carrier transmission module, and the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiving and transmitting bus high-speed UART (HSU); the microcontroller employs an Arduino UNO Rev3 development board: the carrier transmission module adopts PN532 NFC board with antenna, wherein: pins A4, A5, 2 and 3 of the microcontroller are correspondingly connected with pins MO/SDA/TX and NSS/SCL/RX, IRO, RST # of the carrier transmission module; the microcontroller uses Arduino language to communicate with the carrier transmission module by IIC protocol.

A detailed example of the structure shown in fig. 1 is as follows:

the microcontroller in the control module employs an Arduino UNO Rev3 development board having a digital signal I/O pin hole 14 way, wherein pin hole 6 way of the PWM output can be provided. The device consists of 6 paths of analog signal input pin holes, one 16MHz quartz crystal oscillator, one Universal Serial Bus (USB) interface, one on-line serial programming ICSP data interface, one DC 2.1mm female power socket and a RESET button. The computer can be started to operate only by connecting the computer with the computer through a USB data line or by using an AC-DC power adapter or by providing power through a battery. All elements of the single chip microcomputer operation are included in the Arduino UNO.

The ATmega16U2 programming is configured as a universal Serial bus and Serial interface USB to Serial converter, so that driver software can be installed more simply, easily and freely. The ATmega328P IC in Arduino UNO has been pre-programmed and is also provided with a boot program (taking up 0.5KB of memory) allowing the user to upload new code directly to the development board without the use of an external hardware programmer. It has a memory space of 32KB, with the bootstrap program occupying 0.5KB. And SRAM 2KB and EEPROM 1KB, can be read and written through the EEPROM bank.

The Arduino UNO Rev3 development board has the function of automatically selecting power supply, and can be connected with a USB interface to supply power or adopts an alternating-direct power adapter (Wall-Wart) or an external power supply (non-USB) such as a battery to supply power. An ac-DC power adapter (Wall-start) may be connected to a DC 5.5 x 2.1mm male plug via a cable and plugged into a DC 2.1mm female power socket of the development board to provide power to the development board. When battery powered, then, battery leads may be connected to the VIN and GND pin holes of the development board. In general, the three methods supply power to the development board, which are USB interface (DC 5V), DC 2.1mm female power socket (DC 7-12V) or VIN pin (DC 7-12V) of the development board, respectively.

The recommended voltage range for Arduino UNO Rev3 development board is DC 7-12V. Arduino UNO can start operation when the external power supply voltage is DC 6-20V. However, if the external power supply provides a voltage lower than DC 7V, the actual voltage of the DC 5V pin on the development board may be lower than DC 5V, which may cause the Arduino UNO development board to fail to operate in an optimal state, and affect the stability of the operation of the development board. However, if the external power supply provides a voltage higher than DC 12V, the on-board power regulator may burn out due to overheating, damaging the Arduino UNO development board power supply assembly.

In the 14-way Digital Pins on the Arduino UNO development board, each way can be used as a Digital signal INPUT pin or an OUTPUT pin. This can be achieved by using the pin mode pinMode (), digital write (), and digital read () functions. The working voltage of each digital pin is DC 5V. Each digital pin can provide 20mA current to the outside or receive 20mA current from the outside, and is provided with an internal pull-up resistor which is in a disconnected state by default, and the resistance value is 20-50kΩ. The maximum allowable passing current is 40mA, which must not be exceeded, so as not to damage the development board.

The Arduino UNO Rev3 development board is equipped with a number of means to facilitate its communication with a computer, other Arduino development board, or other single-chip microcomputer. ATmega328 provides a universal asynchronous receiver transmitter bus UART for TTL serial communications (DC 5V), which may be implemented via digital pins 0 (RX) number and 1 (TX) number. The ATmega16U2 chip carried by Arduino UNO Rev3 can be connected with a serial communication interface through a universal serial bus USB, and a COM port for software simulation is provided in a computer (a Windows system needs to be configured with an inf file for identification, and an OSX and Linux system can automatically identify the COM port). Inclusion of a serial monitor in the Arduino IDE software allows some simple text data to be sent (RX) and received (TX) through the Arduino UNO Rev3 development board. When the computer and development board transmit data through the ATmega16U2 chip and universal serial bus USB interface, the RX (transmit) and TX (receive) LED lights on the development board will blink. Serial communication over digital pins 0 (RX) and 1 (TX) are not applicable. Serial communication can be achieved through a software serial library on any one of the digital pins of Arduino UNO Rev 3. ATmega328P supports universal asynchronous receiver/transmitter (UART) High Speed (HSU), serial Peripheral Interface (SPI), and integrated circuit bus IIC (TWI) communications. To simplify operation using the IIC bus, the Arduino IDE software includes a wire library.

The carrier transmission module adopts a PN532 NFC board with an antenna, and the PN532 NFC board with the antenna is provided with a ROM 40KB and a RAM 1KB based on an 80C51 kernel. The hardware interface of PN532 NFC board with antenna is: serial peripheral interface SPI, integrated circuit bus IIC, universal asynchronous receiver/transmitter (UART) High Speed UART (HSU).

The PN532 NFC board with the antenna can select three configuration modes through two pins:

standard mode: default mode of PN532 NFC board with antenna

Simulation mode: PN532 NFC board with antenna uses serial port RS232 to keep the baud rate 9.6kbps in simulation mode. The IRQ pin emulation is supported, and the P70_IRQ pin is low when an interrupt occurs.

Radio frequency field on mode: PN532 NFC board with antenna is in radio frequency field on mode, PN532 opens radio frequency immediately after reset. The p33_int1 pin and the P34/sic_clk pin can select a modulation mode and a baud rate, and continuously transmit byte data. In this mode, the temperature sensor is not available.

PN532 NFC plate with antenna working mode: the PN532 NFC board with the antenna can be switched into five different working modes through firmware so as to meet various requirements. Respectively analog card, initiator/PCD, target card/PICC, low battery, standby. Or switching the working mode according to the command of the master controller (singlechip) and the internal state of PN 532.

The PN532 NFC board with antenna is configured into a target card/PICC mode. If a target card is activated, PN532 enters initiator/PCD mode from target card/PICC mode.

The master controller interface is set as:

the Arduino UNO Rev3 development board of the system can interact through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiver/transmitter (HSU) and a PN 532. And selecting a communication connection mode of the master controller interface through

pins

16 and 17.

The master interface selects the following:

if the serial peripheral interface SPI is used and the power source PVDD is not connected, the low-voltage lowVbat mode is required to be entered.

Between carrier wave transmission module (PN 532 NFC board with antenna) and microcontroller (Arduino UNO Rev3 development board), besides the communication interface, it also needs to connect P70_IRQ pin, so that PN532 can quickly inform controller when there is command.

Interaction of microcontroller (Arduino UNO Rev3 development board) and carrier transmission module (PN 532 NFC board with antenna):

half duplex communication is carried out between a microcontroller (Arduino UNO Rev3 development board) and a carrier transmission module (PN 532 NFC board with an antenna), and is bidirectional communication alternately carried out, so that Transmission (TX) and Reception (RX) cannot be carried out in two directions simultaneously. The communication is performed in a frame format. There are five types of frames:

(1) Standard frame: and a bi-directionally transmitted frame. Commands are sent from the microcontroller (Arduino UNO Rev3 development board) to the PN532 and responses are sent from the PN532 to the microcontroller (Arduino UNO Rev3 development board), with a maximum transmission of data 255 Byte.

(2) Extension frame: and a bi-directionally transmitted frame. An extended frame may also be used where data is less than 255 bytes, and where the frame is effective to transmit data up to 264 bytes.

(3) ACK frame: and a bi-directionally transmitted frame. The response frame may be sent by the microcontroller (Arduino UNO Rev3 development board) to the PN532 or the PN532 to the microcontroller (Arduino UNO Rev3 development board).

(4) NACK frame: a unidirectionally transmitted frame. The microcontroller (Arduino UNO Rev3 development board) sends the data to the PN532, and notifies the PN532 that the reception of the last response frame microcontroller (Arduino UNO Rev3 development board) failed, so that the PN532 resends the last data to the controller (single chip microcomputer).

(5) Error frame: a unidirectionally transmitted frame. PN532 is sent to the microcontroller (Arduino UNO Rev3 development board) informing the microcontroller (Arduino UNO Rev3 development board) that an error has occurred at the application layer.

Command of PN532 NFC board with antenna:

the frame structure contains the type and amount of data. INPUT: the microcontroller (Arduino UNO Rev3 development board) transmits data to PN532, outputting OUTPUT: PN532 transmits data to a microcontroller (Arduino UNO Rev3 development board). PN532 may be configured by command to either the initiator/PCD mode or the target card/PICC mode. The lower diagram gives the instruction Code "Command Code (CC)", i.e. the frame of the microcontroller (Arduino UNO Rev3 development board) to PN 532.

The frame from the singlechip to PN532 is as follows:

00

FF

LEN

LCS

D4

CC

Optional Input Data

DCS

00

FF

LEN

LCS

D5

CC+1

Optional Output Data

DCS

00

RF radio frequency interaction command:

commands that may be used when PN532 is in initiator mode or target card mode are indicated by "O" in the following table.

PN532 RF radio frequency interaction command table is as follows

Configuration of the interface:

and the PN532 NFC board with the antenna can be provided with a jumper wire to select the interface connection mode. The PN532 board supports three connection modes, namely UART, SPI, IIC. The corresponding relation between the setting positions of the jumper SET0 and SET1 and the connection mode is as follows:

the jumper wire setting table of each main control interface is as follows:

and (3) line connection:

the microcontroller (Arduino UNO Rev3 development board) uses the Arduino language, which communicates with PN532 using IIC protocol for code setup convenience. IIC, inter-Integrated Circuit (integrated circuit bus), also known as I2C, is a synchronous serial bus designed by Philips semiconductor (now Enzhi semiconductor NXP Semiconductors) in the eighties of the twentieth century, which has the characteristics of simplicity, bi-direction and two-wire system, and is mainly used for connecting an Integrated Circuit (ICS), a plurality of chips can be connected to the same IIC bus structure, and each of the chips can be used as a control source for data transmission, that is, the IIC is a multidirectional control bus. This bus type allows a certain simplification of the signaling bus interface.

PN532 board and Arduino UNO board are connected according to IIC protocol, the connection method is as follows:

In order to control the locking state of the door lock, the starting and stopping and running directions of the door lock motor are required to be controlled. A relay module is provided in the device. Arduino UNO and 4-way relay board connection are as follows:

UNO board pin	Relay board pin (High in)
		3.3V	V1
GND	G1

4	S1
		5	S2
6	S3
		7	S4

。

And (3) setting operation logic:

1. and the door lock control module is used for:

in order to realize the opening and closing functions of the door lock, the PN532 identification card ID of the device module 1 is compared with a preset ID in a program, and the comparison result with the preset ID1ID2ID3 respectively controls the on-off of the 1-4 relays in the relay board 1, so that the state of a door lock motor is controlled.

The NFC card mode is set in the mobile phone, card IDs required by executing all operations are prestored, when unlocking and locking operations are executed, the function key is firstly clicked in the mobile phone App, the NFC module of the mobile phone starts card simulation, at the moment, the mobile phone is close to the PN532 antenna of the device, the card IDs are successfully compared, and the device can execute corresponding operations according to the intention of an operator. If the card ID comparison fails, the vehicle gives an audible and visual alarm.

1. And comparing the signals which accord with the preset ID1 and give the pin 4 a high potential, sending the signals to the pin S1 of the relay board 1 through a connecting wire, enabling the relay 1 to be electrified and attracted, and giving the pin 4 a low potential after 2S, so that the relay 1 is powered off and released. The purpose of this action is to provide power to the unlocking operation of the cabin door lock motor.

2. And comparing the signals which accord with the preset ID2 and give the pin 5 a high potential, sending the signals to the pin S2 of the relay board 1 through a connecting wire, enabling the relay 2 to be electrified and attracted, and giving the pin 5 a low potential after 2S, so that the relay 2 is powered off and released. The purpose of this action is to provide power to the latching operation of the cabin door lock motor.

3. And comparing the signals which accord with the preset ID3 and give the pin 6 a high potential, sending the signals to the pin S3 of the relay board 1 through a connecting wire, enabling the relay 3 to be electrified and attracted, and giving the pin 6 a low potential after 2S, so that the relay 3 is powered off and released. The purpose of this action is to provide power to the unlocking operation of the motor of the trunk door lock.

4. When the card ID is not matched with the preset ID1 ID2 ID3 in the program, a high potential is given to the pin 7, a signal is sent to the pin S4 of the relay board 1 through a connecting wire, the relay 4 is electrified and closed, and after 2S, a low potential is given to the pin 7, and then the relay 4 is powered off and released. The purpose of this action is to provide power to the burglar alarm system, which causes the vehicle to emit an audible and visual alarm that may be illegally intruded by a person.

2. An ignition control module:

in order to achieve both comfort and safety and improve the integration level of equipment. The device also has the function of controlling the start and stop of the vehicle engine. This function is implemented by another set of PN532, UNO, relay boards. After the PN532 of the device module 2 identifies the ID, the ID is compared with the ID4 preset in the program, and the comparison result controls the on-off of the 4-8 relays in the relay board 2, thereby controlling the on-off of the vehicle power supply and the start-stop state of the engine.

The ignition switch of the automobile has four action positions of 0 OFF (LOCK), 1 ACC, 2 ON and 3 START. The function of each action position will be described one by one in the two sequences of start and stop.

The starting sequence of the boarding (0-1-2-3-2):

when the ignition switch is placed at the 0 OFF (LOCK) position, only the position can pull out the car key, the steering wheel falls down to LOCK when the key is pulled out, the steering wheel is inserted into the key to unlock, all electric appliances in the car are powered OFF, and the engine is stopped. This location should be used for longer vehicle stops or for drivers to leave the vehicle for locking.

When the ignition switch is placed at the 1 ACC position, the electric appliances in the automobile are electrified (such as an instrument, lamplight, a loudspeaker, a windshield wiper, a sound box, a cigarette lighter 12V power supply and the like), the ECU power supply is powered off, the engine is stopped, and a driver can continue to use a comfort function on the automobile when temporarily stopping, so that the ignition switch can be placed at the ACC position as required. The use of electrical appliances in the vehicle at this location for a long period of time may cause battery starvation and engine failure.

When the ignition switch is arranged at the position of 2 ON, all electric appliances in the vehicle are electrified (electric appliances such as an air conditioner ventilator are added on the basis of ACC), the ECU is electrified and starts self-checking, the oil pump works to establish oil pressure, and the ignition system is ready for starting. If the electric appliance in the vehicle is used at the position under the stop state of the engine for a long time, the electric appliance can also cause the power shortage of the storage battery, and attention needs to be paid.

When the ignition switch is placed at the 3 START position, the hand needs to keep the screwing force, and the 3 START position is self-reset to the 2 ON position. The 3 START position is on the basis of 2 ON positions, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started. The original electrified part of the electric appliances are powered off (such as a 12V cigar lighter power supply and the like) so as to ensure that the electric power supply of the starter is sufficient, and the engine can be started successfully.

After the engine is successfully started, the ignition switch is automatically reset to the position of 2 ON from the position of 3 START, the engine keeps running, the generator supplies power to all electric appliances on the automobile and charges a storage battery, and the idle speed working condition of the automobile is the standby working condition before normal running is achieved.

The off-train stopping sequence (2-1-0):

when the ignition switch is placed at the position of 2 ON, the engine keeps running, the generator supplies power to all electric appliances on the vehicle, the storage battery is charged, and the vehicle is in an idle or running working condition.

When the ignition switch is placed at the 1 ACC position, the engine ignition system stops working, the engine is stopped, the ECU power supply is powered off, and the in-vehicle electric appliances (such as an instrument, lamplight, a loudspeaker, a windshield wiper, a sound box, a 12V cigarette lighter power supply and the like) are powered on. The driver can temporarily park the vehicle for use with a comfortable function.

When the ignition switch is placed at the 0 OFF (LOCK) position, all electric appliances in the vehicle are powered OFF, the engine is stopped, and when a key is pulled out, the steering wheel falls OFF to LOCK, and four doors are automatically unlocked. The driver should lock the vehicle away from the vehicle and use this position.

The device realizes the substitution of the key ignition switch function:

and comparing the signals to meet the preset ID4, giving a high potential to the pin 8, and sending the signals to the pin S1 of the relay board 2 through the connecting wire, so that the relay 5 is electrically attracted. The purpose of this action is to control steering wheel unlocking.

After time delay of 0.5s, a high potential is given to the pin 9, and the relay 6 is electrically attracted. The purpose of this action is to turn on the ACC circuit of the ignition switch. In-car electrical distribution apparatus (such as instrument, light, loudspeaker, windshield wiper, stereo set, cigar lighter 12V power etc.), ECU power outage, engine shutdown.

After a delay of 1s, a high potential is given to the pin 10, and the relay 7 is electrified to be attracted. The purpose of this action is to turn ON the ON circuit of the ignition switch. All electric appliances in the vehicle are electrified (electric appliances such as an air conditioner ventilator are added on the basis of ACC), the ECU is electrified and starts self-checking, the oil pump works to establish oil pressure, and the ignition system is ready for starting.

After 2s of delay, a high potential is given to the pin 10, the relay 8 is electrified and closed, and after 3s of delay, a low potential is given to the pin 10, and then the relay 8 is electrified and released. The purpose of this action is to turn on the START circuit of the ignition switch. The 3 START position is on the basis of 2 ON positions, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started. The original electrified part of the electric appliances are powered off (such as a 12V cigar lighter power supply and the like) so as to ensure that the electric power supply of the starter is sufficient, and the engine can be started successfully.

In this embodiment, the NFC antenna of the carrier transmission module is installed near the front windshield glass or the door lock handle of the automobile 11, the NFC antenna is an annular coil, and is embedded and installed inside the door handle 12, or the NFC antenna can be encapsulated inside when the door handle is injection molded; the microcontroller and four-way relay board are mounted in a hidden space 13 below the center console, as shown in fig. 6 and 7.

Claims

1. A control method of an automobile central door lock control device based on NFC near field communication technology comprises the following steps:

(1) The system building step: a mobile device carrying NFC function, a control module and a four-way relay board are adopted to form a system, wherein the control module comprises a microcontroller and a carrier transmission module, and the microcontroller interacts with the carrier transmission module through a serial peripheral interface SPI, an integrated circuit bus IIC or a universal asynchronous receiving and transmitting bus high-speed UART; the microcontroller employs an Arduino UNO Rev3 development board: the carrier transmission module adopts PN532 NFC board with antenna, wherein: pins A4, A5, 2 and 3 of the microcontroller are correspondingly connected with pins MO/SDA/TX and NSS/SCL/RX, IRO, RST # of the carrier transmission module; the microcontroller uses Arduino language to communicate with the carrier transmission module by adopting IIC protocol;

(2) An interface setting step: the jumper wire of the main control interface of the adopted carrier transmission module is set as follows:

(3) A circuit connection step: the carrier transmission module and the microcontroller are connected according to the IIC protocol, and the connection method is as follows:

UNO board pin PN532 board pin 5V 5V GND GND A4 MO/SDA/TX AS NSS/SCL/RX 2 IRO 3 RST#

The microcontroller and four-way relay board connection method is as follows:

UNO board pin Relay board pin 3.3V V1 GND G1 4 S1 5 S2 6 S3 7 S4

；

(4) The operation logic steps are as follows:

2) An ignition control step: the carrier transmission module recognizes the ID and then compares with the preset ID4 in the program, and the comparison result controls the on-off of the 4-8 relays in the relay board 2, thereby controlling the on-off of the vehicle power supply and the start-stop state of the engine, and the method is characterized in that: in the door lock control step, the specific control method comprises the following steps:

2. The control method of the automobile central door lock control device based on the NFC technology according to claim 1, wherein the control method comprises the following steps: in the door lock control step, the specific control method comprises the following steps:

the automobile ignition switch has four action positions of 0OFF, 1ACC, 2ON and 3 START; then introducing the functions of each action position one by one according to the two sequences of starting and stopping;

and (3) loading starting sequence:

when the ignition switch is arranged at the 0OFF position, only the position can pull out the car key, the steering wheel falls OFF the lock when the key is pulled out, the steering wheel is unlocked after the key is inserted, all electric appliances in the car are powered OFF, and the engine is stopped; the vehicle should be stopped for a long time or the driver needs to leave the vehicle to lock the vehicle;

when the ignition switch is arranged at the position of 1ACC, partial electric appliances including instruments, lights, horns, windshield wipers, sound and 12V power supplies of a cigar lighter in the vehicle are electrified, the ECU power supply is powered off, the engine is stopped, a driver continues to use a comfort function on the vehicle when temporarily stopping, and the ignition switch can be arranged at the position of ACC according to the requirement; the electric appliances in the vehicle can cause the power shortage of the storage battery when the vehicle is used at the position for a long time, and the engine can not be started;

when the ignition switch is arranged at the 2ON position, all electric appliances in the vehicle are electrified, the electric appliances comprising the air conditioner ventilator are additionally electrified ON the basis of ACC, the ECU is electrified and starts self-checking, the oil pump works to establish oil pressure, and the ignition system is also ready for starting; if the electric appliance in the vehicle is used at the position in the engine stop state for a long time, the battery is also deficient in power, and attention is paid;

When the ignition switch is placed at the 3START position, the hand is required to keep the twisting force, and the 3START position is self-reset to the 2ON position; the 3START position is ON the basis of the 2ON position, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started; the power of the electric appliance, which is originally powered on and comprises a 12V cigar lighter power supply, is cut off to ensure that the power supply of the starter is sufficient, and the engine can be started successfully;

after the engine is successfully started, the ignition switch is automatically reset to the 2ON position from the 3START position by looking at a tachometer and listening to sound, the engine keeps running, and the generator supplies power to all electric appliances ON the automobile and charges a storage battery, so that the idle working condition of the automobile is the standby working condition before normal running is entered;

and (5) stopping order of getting off:

when the ignition switch is placed at the 2ON position, the engine keeps running, the generator supplies power to all electric appliances ON the vehicle and charges a storage battery, and the vehicle is in an idle speed or running working condition;

when the ignition switch is arranged at the position of 1ACC, the engine ignition system stops working, the engine is stopped, the ECU power supply is cut off, and partial electric appliances including an instrument, lamplight, a loudspeaker, a windshield wiper, a sound and a cigar lighter 12V power supply are electrified in the vehicle; the driver can temporarily park the vehicle for use with a comfortable function;

When the ignition switch is arranged at the 0OFF position, all electric appliances in the vehicle are powered OFF, the engine is stopped, the steering wheel falls OFF to lock when the key is pulled out, and the four doors are automatically unlocked; the driver needs to lock the vehicle to leave the vehicle and should use the position;

the device realizes the substitution of the key ignition switch function:

after 2s of delay, a high potential is given to the pin 10, the relay 8 is electrified and closed, and after 3s of delay, a low potential is given to the pin 10, and then the relay 8 is electrified and released; the purpose of this action is to turn on the START circuit of the ignition switch; the 3START position is ON the basis of the 2ON position, a starter power supply is connected, a starter gear is hung into a flywheel to drive an engine crankshaft, an ignition system STARTs to work, and the engine is started; the portion of the electrical appliance that originally was powered on, including the 12V cigar lighter power source, was powered off to ensure that the power supply of the starter was sufficient, and in total, that the engine could be successfully started.