CN202110568U - 2.4GHz RFID read-write equipment - Google Patents

Abstract

The utility model discloses 2.4GHz RFID (Radio Frequency Identification) read-write equipment, which comprises a main controller, a radio-frequency transceiver module, a serial communicating module, a keyboard module, a storage module, and an LCD display screen, wherein the main controller is used for receiving commands acquired from a keyboard and transmitting the commands from the 2.4GHz radio-frequency transceiver module, receiving feedback signals from an activated radio-frequency card through the radio-frequency transceiver module, and reading out data from the storage module for processing; the radio-frequency transceiver module is used for transmitting commands of the main controller and receiving signals fed back by the radio-frequency card; the serial communicating module is used for transmitting data between the read-write equipment and a computer; the keyboard module is used for inputting commands to the main controller; the storage module is used for storing radio frequency tag data; and the LCD display screen is used for displaying the commands input by the keyboard module connected therewith, and the process results of the main controller or the data received by the serial communicating module. The 2.4GHz RFID read-write equipment has the advantages of long read-write distance, large storage capacity, etc.

Description

A kind of 2.4GHz RFID read-write equipment

Technical field

The utility model relates to the RFID read-write equipment, is meant a kind of 2.4GHz RFID read-write equipment especially.

Background technology

The RFID technology all has comparatively ripe and advanced rfid system at present in the U.S., Britain, Germany, Sweden, Switzerland, Japan, South Africa.Wherein, low frequency closely rfid system mainly concentrate on the 125kHz system; High frequency far Distance RFID system mainly concentrates 13.56MHz, 915MHz, 2.45GHz, 5.8GHz.

China also develop aspect the RFID Study on Technology very fast.Aspect RFID technical research and product development, domestic technical capability and the system integration ability that has had independent development low frequency, high frequency and microwave RFID electronic tag and card reader.And the gap between the external RFID advanced technology is mainly reflected in RFID chip technology aspect.However, aspect label chip design and exploitation, domestic existing a plurality of successful low frequency RF ID system label chips appear on the market.RFID does not also form unified globalization standard, and market is the multiple standards and the situation of depositing, but along with the beginning of RFID in global logistics industry large-scale application, the unification of RFID standard has obtained the well recognized of industry.

RFID The Application of Technology category can be divided into four types: Electronic Article Surveillance EAS (Electronic Article Surveillance, mobile data collection (Portable data capture, network system (Networked systems), positioning system (Positioning systems).Though more based on 2.4GHz RFID read-write equipment, there is the problem of poor-performing.

The utility model content

In view of this, the utility model is to provide a kind of 2.4GHz RFID read-write equipment, to solve the problem of above-mentioned 2.4GHz RFID read-write equipment poor-performing.

For addressing the above problem, the utility model provides a kind of 2.4GHz RFID read-write equipment, comprising: primary controller is used for receiving the instruction that obtains from keyboard, and the RF receiving and transmission module of said instruction through 2.4GHz is sent; Through the radio-frequency card receiving feedback signals of said RF receiving and transmission module, handle from said memory module reading of data from being activated;

The RF receiving and transmission module of the 2.4GHz that is connected with said primary controller, the instruction that is used to send said primary controller receives the signal that said radio-frequency card feeds back;

With the serial communication module that said primary controller is connected, be used between said device and computing machine, transmitting data;

With the Keysheet module that said primary controller is connected, be used for to said primary controller input instruction;

With the memory module that said primary controller is connected, be used to store the RF tag data;

LCD display is used to show the instruction of the Keysheet module input of connection, and the data that receive of the result of said primary controller or said serial communication module.

Preferably, said serial communication module is the communication module of RSR232 interface.

Preferably, said primary controller comprises plural full duplex serial port, and at least one is used for the data transmission between primary controller and the RF receiving and transmission module, and at least one is used for the data communication between serial communication module and the computing machine.

Preferably, said RF receiving and transmission module comprises:

Interconnective transmitter module, receiver module, power amplifier, low noise amplifier, frequency synthesizer and GFSK wave filter.

Preferably, said memory module has serial SPI interface.

The utlity model has following advantage:

(1) to the radio-frequency card read-write capability of nRF2401 as rf chip.Support 2.4GHz radio frequency specification protocol, more than the reading/writing distance 10m;

(2) system's online upgrading function.Have abundant software interface, be the condition that secondary system is developed and online upgrading is provided convenience;

(3) mass data storage function.Have high capacity Flash storer and reliable data store organisation, can satisfy the needs that handheld device is preserved data, storer possesses serial SPI interface, need not to change the cutting that the hardware pcb board can be realized memory capacity;

(4) real-time status Presentation Function.Has 128 * 16 LCD display module, for the user provides friendly operation interface easily, display operation state in real time;

(5) with the real-time Communication for Power function of PC.Carry out the real time data exchange through RSR232 interface and computing machine.

Description of drawings

Fig. 1 is the structural drawing of embodiment one;

Fig. 2 is the structural drawing of embodiment two;

Fig. 3 is the process flow diagram of master routine;

Fig. 4 is the process flow diagram that card reader is sent data;

Fig. 5 is the process flow diagram that card reader receives data;

Fig. 6 is the process flow diagram of keyboard scan program.

Embodiment

For clearly demonstrating the technical scheme in the utility model, provide preferred embodiment below and be described with reference to the accompanying drawings.

Referring to Fig. 1, the read-write equipment among the embodiment 1 comprises: this card reading system mainly is made up of controller, RF transceiver, liquid crystal display, clock chip, computing machine PORT COM and keyboard.Specify each parts below.

Primary controller

Primary controller is the part in the control module, through combining with application software, has controlled the operation of each module of system.Comprise: the data of radio frequency transceiver are sent and received; Effective storage of RF tag data; From clock chip real-time search time information reception and storage; The data presentation of LCD and and computing machine between data transmission.The microcontroller that the utility model is selected has plural full duplex serial port, a data transmission that is used between primary controller and the RF transceiver, and another then is used to read the data communication of sheet device and computing machine.In order to realize the requirement of the utility model to system, this main control chip must have abundant serial 1/O mouth resource, has the rapid and reliable literacy.JTAG (Joint Test Action Group) interface is mainly used in on-line debugging and fuse bit of master controller etc. is set.

RF transceiver

All adopt the radio-frequency receiving-transmitting mode that data are transmitted in many applications at present, like wireless identification tag identification, non-contact RF smart card, gate control system, micro radio network, cell call, radio meter register, industrial data acquisition system, wireless remote-control system or the like.These adopt bluetooth and rf chip [7] mostly, and the research that particularly works in 2.4-2.5GHz ISM band rf chip has become a focus.The rf chip that therefore will adopt a 2.4-2.5GHz of working in ISM band is as the sending and receiving end of reading the sheet device.

Radio communication commonly used at present mainly contains IEEE802.11, infrared communication, bluetooth and some radio transmitting and receiving chips.What wherein IEEE802.11b realized is tangible, particular network, and transmission range is long, speed is fast, can satisfy the network operation that the user moves a large amount of occupied bandwidths, just as on cable LAN.IEEE802.11b relatively is suitable for the enterprise wireless networks in the office, is suitable for use in high-speed radio transmission such as image, and coverage reaches 100 meters.

The serial ports display

Can be convenient for carrying as one; In goods storage Tibetan goods is cleared fast; And the hand-held that in large-scale garage, the vehicle of busy discrepancy is carried out current management fast and effectively reads the sheet device, must subsidiary enough display of data demonstration amount, but video data information.Along with e-dictionary, MP3, the development need of miniature electric equipment such as MP4, mobile phone, the LCD on the market is multifarious.In order to save the demand to the microcontroller pin, the utility model is selected a serial line interface LCD.Can show that the every screen of English display can reach 50 more than the letter by Chinese and English, 25 of Chinese are more than the word.

The serial ports keyboard

Keyboard classes of today is various, from computor-keyboard to the e-dictionary keyboard, perhaps from TV remote controller to the DISKMAN line traffic control, its configuration design is varied, but all is to be made up of keyboard and outer defeated interface basically.Interface mode has simple parallel port, serial mode, and complicated usb mode is also arranged.Because the pin resource-constrained of primary controller, will design the 4X4 keyboard of a serial interface mode in the utility model, through utilizing 16 keyboards, one pair of 4 input nand gate and microcontroller ATmega16 realize.

The computing machine communication terminal

Based on the requirement of the utility model compunication, select RS232 as communication protocol.The hardware of RS232 is realized simple, and therefore a lot of this communication modes that adopted are arranged in traditional device.General IC sheet gate inhibition attendance checking system also uses the RS232 interface to communicate by letter with PC.

Referring to Fig. 2, the utility model also provides a kind of radio frequency read-write equipment, and its groundwork flow process is following:

(1) master controller obtains user instruction through the user key-press operation and it is encoded;

(2) order behind the coding is modulated to the radiofrequency signal of frequency at 2.4GHz by the radio frequency read-write chip, launches through antenna then;

(3) when radio-frequency card gets into effective perform region of antenna, produce induction current, radio-frequency card obtains energy and is activated;

(4) the radio-frequency card analysis order of receiving, and corresponding information sent through the card built-in aerial;

The carrier signal of (5) sending from radio-frequency card is received by the antenna of read write line, sends master controller back to through the demodulation of radio frequency read-write chip;

(6) read write line is decoded from radio frequency read-write chip read response, then display operation result on LCD.

In addition, the software systems of read write line need be judged the legitimacy of this card according to logical operation, make corresponding processing and control to different settings, send the command signal control executing mechanism and make action.

Master controller among Fig. 2 adopts ATmega16 AVR to realize.ATmega16 AVR kernel has abundant instruction set and 32 general purpose working registers.All registers all directly are connected with ALU (ALU), make an instruction can in a clock period, visit two independently registers simultaneously.This structure has improved code efficiency greatly, and has and be up to 10 times data throughput than common CISC microcontroller.

RF receiving and transmission module adopts nRF2401 to realize the radiofrequency signal transmitting-receiving, and it is a powerful monolithic radio frequency GFSK transceiving chip, is operated in 2.4-2.5GHz ISM frequency; Its communication channel can reach 125; Satisfy multi-point and frequency hopping communications needs, operating rate is 1Mbps, maximum transmission power 0dB; Peripheral cell is few, built in hardware CRC (CRC) and the control of point-to-multipoint delivery address.The receiving and transmitting front end of nRF2401 has disposed power amplifier and low noise amplifier, also has frequency synthesizer and GFSK wave filter.In addition, the also built-in detuner of nRF2401, clock recovery data amplitude limiter, address decoder, CRC coding decoder, and FIFO stack area.

The nRF2401 chip has a very outstanding characteristic, promptly has two kinds of communication patterns: Direct Model (Direct Mode) and burst mode (ShockBurstTM Mode).The working method of Direct Model is the same with the working method of conventional radio frequency transceiver, and when sending, transceiver adds check code in the back of address code and data automatically.Burst mode utilizes the FIFO stack area of chip internal; Data are sent into from the low speed microcontroller; Go out with transmitted at high speed again and (reach as high as 1Mbps; Address and check code are added automatically by hardware and remove, and use this transceiver mode, and the microprocessor controls chip is more effectively worked; Make radiofrequency signal with transmitted at high speed, strong interference immunity; Also reduce the average current of total system.

Adopt LCD LCD (Liquid Crystal Display) to come display system information among the design.Compare with LED, LCD have rich display information, low in energy consumption, volume is little, incomparable advantage such as in light weight, ultra-thin, therefore be widely used in monolithic processor controlled intelligence instrument, instrument and the low power dissipation electron product.LCD can be divided into section formula LCD, character formula LCD and diagram form LCD.Wherein, section formula LCD and character formula LCD can only be used for the simple displaying of character and numeral, can not satisfy the requirement that graph curve and Chinese character show; And diagram form LCD not only can character display, numeral, can also show various figures, curve and Chinese character, and can realize functions such as screen rolling up and down, animation, subregion windowing, counter-rotating, flicker.

Serial communication module selects for use RS-232 as the interface mode between hand-held set and the PC.

Rs-232 standard is the communication protocol that the EIA of EIA (Electronic Industries Association) develops with companies such as BELL, and it is suitable for the communication of data transmission rate in 0～20kbps scope.Typical R S-232 signal is being swung between positive negative level, when sending data, the positive level of transmitting terminal driver output+5～+ 15V between, negative level-5～-15V between.When no datat is transmitted, on the line Transistor-Transistor Logic level, from beginning to transfer data to end, level returns Transistor-Transistor Logic level from Transistor-Transistor Logic level to the RS-232 level again on the line.The typical operation level of receiver+3～+ 12V and-3～-12V between.Because the difference of transmission level and incoming level is merely about 2V to 3V, so its common mode inhibition capacity is poor, adds the distributed capacitance on the twisted-pair feeder, its transmitting range is about 15 meters to the maximum, and flank speed is 20kb/s.RS-232 designs for point-to-point (promptly only using a pair of receiving and sending equipment) communication, and its driver load is 3～7k Ω.So RS-232 is fit to the communication between the local device.

Adopt the MAX3232 chip to realize the conversion between RS-232 level and the Transistor-Transistor Logic level.

For the power consumption of saving, card reader can get into the Standby pattern automatically after the also executive system initialization of starting shooting, when only receiving the look-at-me that produces because of the keyboard key entry, just change normal mode of operation over to.Referring to process flow diagram shown in Figure 3;, any one key of keyboard all can produce a look-at-me after being pressed; Primary controller just carries out data processing to the keyboard key entry instruction that receives after detecting this look-at-me; Check whether effective, if find invalid (as artificial mistake by), then system does not carry out any instruction and returns the Standby pattern; Be then the RF tag information that receives to be transferred to RF transceiver through the serial port mode by the RF tag search instruction if detect, and control RF transceiver emission request signal, change the receiving mode wait-for-response then over to.Then do not resend request signal, wait-for-response then if there is response in the fixed time; Surpass the instruction number of times if repeat to send number of times, then judge by " driftlessness label in the field of search "; If receive response, then begin the radio-frequency information of received RF tag feedback, carry out simultaneously CRC check guarantee to communicate by letter errorless, then with the data storage that receives in external storage, store real-time search time of the information that produces by clock chip simultaneously.Display shows the whole operation process information of carrying out.

If detecting keyboard key entry instruction is to communicate with computing machine, perhaps prestored message is browsed and is waited other instructions in the reading card device, and this keyboard of the then corresponding execution of system is keyed in instruction.

After execution command finished, system can get into idle pulley automatically.

The transmission flow of ShockBurstTM Mode can comprise referring to Fig. 4:

The interface pin of using is CE, CLK1, DATA.

(1) when microcontroller has data to send, CE is put height, make nRF2401 work be in transceiver mode;

(2) nRF2401 is sent into chronologically with the data that will send in the address of acceptance point;

(3) microcontroller is put CE low, excites nRF2401 to carry out ShockBurstTM Mode emission;

(4) the ShockBurstTM Mode of nRF2401 is transmitted to the radio-frequency front-end power supply;

(5) rf data packing (adding prefix, CRC check sign indicating number);

(6) transmitted at high speed packet;

(7) emission is accomplished, and nRF2401 gets into waiting status.

The reception flow process of ShockBurstTM Mode can comprise referring to Fig. 5:

The interface pin of using is CE, DR1, CLK1 and DATA (is example with channel 1).

(1) disposes this machine address and the packet size that will receive;

(2) get into accepting state, put height to CE;

(3) behind the 200us, nRF2401 gets into monitored state, waits for the arrival of packet;

(4) when receiving proper data bag (correct address and CRC check sign indicating number), nRF2401 removes prefix, address and CRC check position automatically;

(5) nRF2401 causes that through putting height to DR1 (ready for data signal) microcontroller interrupts, and the notice microcontroller can carry out Data Receiving;

(6) microcontroller shifts out data from nRF2401;

(7) all data have been moved, and nRF2401 puts DR1 low, if CE this moment is high, then wait for next packet, if CE is low, then begin other workflow.

Because the common mechanical button can produce shake, judge that for correct button must adopt the method for shaking, otherwise the result of misoperation can occur.Adopt software to go to tremble, mainly use the line inversion method to scan, the key assignments computing method are: row value+train value, no key returns sexadecimal number 0xFF when pressing.The keyboard scan flow process is as shown in Figure 6

The utlity model has following advantage:

(1) to the radio-frequency card read-write capability of nRF2401 as rf chip.Support 2.4GHz radio frequency specification protocol, more than the reading/writing distance 10m;

(2) system's online upgrading function.Have abundant software interface, be the condition that secondary system is developed and online upgrading is provided convenience;

(3) mass data storage function.Have high capacity Flash storer and reliable data store organisation, can satisfy the needs that handheld device is preserved data, storer possesses serial SPI interface, need not to change the cutting that the hardware pcb board can be realized memory capacity;

(4) real-time status Presentation Function.Has 128 * 16 LCD display module, for the user provides friendly operation interface easily, display operation state in real time;

(5) with the real-time Communication for Power function of PC.Carry out the real time data exchange through RSR232 interface and computing machine.

For the device of being set forth among each embodiment of the utility model, all within the spirit and principle of the utility model, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection domain of the utility model.

Claims (5)

1. a 2.4GHz RFID read-write equipment is characterized in that, comprising:

Primary controller is used for receiving the instruction that obtains from keyboard, and the RF receiving and transmission module of said instruction through 2.4GHz sent; Through the radio-frequency card receiving feedback signals of said RF receiving and transmission module, handle from said memory module reading of data from being activated;

The RF receiving and transmission module of the 2.4GHz that is connected with said primary controller, the instruction that is used to send said primary controller receives the signal that said radio-frequency card feeds back;

With the serial communication module that said primary controller is connected, be used between said device and computing machine, transmitting upgrade data;

With the Keysheet module that said primary controller is connected, be used for to said primary controller input instruction;

With the memory module that said primary controller is connected, be used to store the RF tag data;

LCD display is used to show the instruction of the Keysheet module input of connection, and the data that receive of the result of said primary controller or said serial communication module.

2. device according to claim 1 is characterized in that, said serial communication module is the communication module of RSR232 interface.

3. device according to claim 1; It is characterized in that; Said primary controller comprises plural full duplex serial port, and at least one is used for the data transmission between primary controller and the RF receiving and transmission module, and at least one is used for the data communication between serial communication module and the computing machine.

4. device according to claim 1 is characterized in that, said RF receiving and transmission module comprises:

Interconnective transmitter module, receiver module, power amplifier, low noise amplifier, frequency synthesizer and GFSK wave filter.

5. device according to claim 1 is characterized in that, said memory module has serial SPI interface.

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