Main program design is read write implement in applying in content to shed storage management, need system of join superstratum WMS, read so write implement the job is under PC monitoring, PC and read write implement correspond with means of principal and subordinate. If the graph is shown 5 times, in this design because send and receive way of chip interior work to pass MCU of the exterior join that cite a base,undertake controlling to in-house register process designing, working way still is included to modify a program in the main program so, rose to read write implement applied flexibility; Still include intensity of RSSI (signal to detect at the same time) , improved the validity that reads access to occupy greatly. After MCU was completing normal electrify restoration and initialization process, whether should PC clew user undertake set of in-house work way is reached revise, if need, turn way of work of manage of place to go modifies a program, otherwise MCU enters preparative work state, preparation receives the relevant executive instruction that the PC sends. Place to go turns to manage after MCU receives an instruction relevant program. Processing ends, return result information and enter again await condition. On the base that spreads storage management to use background in the content that analyses RFID, undertook brief specification to what the design uses label, put forward a kind of RFID to read write implement design program, the key designed RFID to read write implement hardware and software module. Among them, hardware module design basically includes to receive / send module, external interface module, control module and module of power supply management; Software module design basically includes to the main program is designed and prevent conflict programming two parts. RFID(Radio Frequency Identification, radio frequency identifying) the technology is the blame contact that uses communication of wireless radio frequency one kind to realize remote identifying identifies a technology automatically. The photograph of bar code technology that sheds a domain to be used generally with modern other people is compared, it is being read write distance, confidential sex, intelligence to change, the environment gets used to ability and service life respect to have distinct advantage. Current, worldwide inside the content that is aimed at RFID sheds application to exist system of two kinds of coding, one kind is the UID coding system that center of Japanese UID(Ubiquitous ID) offers, another kind is American EPC(Electronic Production Code, electronic product code) the level of code of EPC electron product that round-the-world association raises. The wireless frequency that these two kinds of standards use in place paragraph, the respect such as information digit and applied domain differs somewhat. And our country's official without oneself still standard, but concerned RFID is in 900MHz frequency paragraph applied electromagnetism detects the job is finished already basically, what our country cares most is I SOl8000~6 standard. Substantially EPC standard and IS018000 are not contradictory, shed application to content, EPC mark criterion is more perfect. Additional, to content shedding application, cost is the problem that the enterprise cares most. Below the premise of contented need, choosing lowermost cost is be the first to be affected. Space of work of UHF(915MHz) radio frequency is controlled in 10m probably, can have satisfied content to spread applied demand, and cost should compare small wave band low much. Especially UHF radio frequency allows to use relatively lesser directional antenna, this will make read write implement radiation beam is directional to a specific area, this kind of characteristic makes read write implement can resist come from at other read write implement or the potential interference of catapult. In view of afore-mentioned circumstances, the large-scale application of storage management field flows in our country content to promote RFID system, the article put forward a kind to be based on content to shed what storage management applies to read write implement design method. Should read write implement the design consults EPC standard, use 915MHz job frequency, of the RFID label chip with some company read write for the target, circuit design is simple, application is agile, manufacturing cost is low. The label that of brief introduction of 1 label function designs place to use originally is in for the job the label of Sunday run passive of 860MHz ～ 960MHz, accord with IS018000-6 standard, working space can be amounted to 8.4m(has stereo antenna case and decide) , apply to American content to flow especially supply chain management and logistics safeguard system. This label basically is like next characteristics: (1) receives aerial n of energy part translate into through the imitate circuit of RF front, for in-house circuit power supply. (2) interior bag contains redundant desired result of 16 CRC(loop) encode, have very tall data integrality. (3) is had prevent conflict mechanism quickly, apply oneself to prevented conflict algorithm to realize true internal conflict judgement and prevent conflict. (4) uses 64 EPC code, and interior includes 216 byte user to define storage space oneself. After label enters RF area, label is activationed. If intensity of RF area signal obtains the need of label job energy, criterion label enters preparative work state, wait to receive read write implement sent statement. Label is received and sent data will have accident desired result through CRC. In the meantime, still pass Mancunian encode and FM0 encode to undertake further protection to data, will assure the security of data with this. Read write implement while through exterior command combinative label interior prevents conflict algorithm to realize many label data, read take with write. 2 RFID is read write implement RFID of design hardware design is read write implement in applying in storage management, except finish simple radio frequency signal to send and receive processing besides, still need to join superstratum storehouse runs a system (Warehouse Management System, WMS) , convey the ticket information that receives in WMs, in order to facilitate the system completes the operation such as management of the put in storage of storehouse, check, delivery of cargo from storage. In the meantime, write the message such as the freight lot of article article ticket through WMS. Read so write implement total construction includes 4 module: Receive / send module, control module, external interface module and module of power supply management. Send and receive module of radio frequency circuit to all be formed by radio frequency signal with signal processing two unit are comprised, amplifier of radio frequency power undertakes to the radio frequency signal that already formed power magnifies, the radio frequency signal that linear amplifier receives to place undertakes linear enlarge. What if the watch is shown 1 times,choose chip. In design of radio frequency circuit, prevent and restrain electromagnetism interference, enhance electromagnetism compatibility, it is very important segment. Want to choose the base material with dielectric constant little common difference, undertake dividing a processing to the radio frequency part of circuit and digital part. Radio frequency part should use SMT(to express post type as far as possible) component, had reduced aperture, add layer of screen of ground connection metal in the surface. What specific design narrates each module as follows. 2. 2. 2 prevent conflict programming prevents conflict programming is to read write implement one of programming main component. Should read write implement when entering working state, in its aerial enclothes all label inside limits to will be activationed, be in await condition, prepare to answer at any time read write implement instruction operation, this caused label to read write conflict. To solve this one problem. Interior designed label to be taken oneself prevent conflict mechanism, need to use relevant instruction part only subdesign defends conflict program one kind can. If the graph is shown 6 times,prevent conflict program flow chart. Receive when the label that is in the condition that stimulate a word read write implement when SELECT commands, send oneself UID to give read write implement. If have the ticket of an above,send UID at the same time right now, read write implement circle in the air calm conflict happens, send FAIL to command label, label prevents conflict algorithm to undertake modification to numerical value is being joined related oneself through interior. Later, the label that accords with a condition will send UID to give again read write implement, by read write implement decide conflict, duplicate afore-mentioned operations, until only a label accords with a condition, jump out to defend conflict program, enter label follow-up to handle an order, in the meantime, odd label revises oneself automatically relevant numerical value, take to be read the next time prepare; If do not have the label that accords with a condition right now, read write implement send SUCCESS order, label revises oneself parameter, wait to read write implement detect command. The article analyses current RFID system to shed storage management field to apply the foundation of setting to go up in content in development, put forward a kind to be based on content to shed what storage manages to read write implement design method. Should read write implement the design is simple, application is agile, manufacturing cost is low. The application in storage management will flow to should be read in real thing henceforth write implement, read a few problems that keep the field such as speed, distance, confidential sex in the light of what in applying actually, appear, write to reading implement the design does farther improvement, with making its overall function has substantially rise, stimulative RFID system sheds the large-scale application of storage management field in our country content. Receive / send module to close / the TRF6901 that hair and modulation demodulation chip choose TI company, power magnifies chip chooses the MW4IC915GMBR1 chip of company of Freescale semiconductor device, linear signal magnifies chip chooses the RF2132 of company of RF small parts of an apparatus. TRF6901 chip interior is compositive complete radio frequency is received and send circuit, can comprise radio frequency of a half duplex operation to send and receive circuit. Its job frequency can undertake fine tuning through process designing, frequency limits is 860MHz~930MHz. Chip of enlarge of power of a MW4IC915 is for GSM application design broad frequency band, it used technology of Freeseale company's newest big voltage LDMOSIC, can work in frequency of 750MHz ～ 1000MHz paragraph inside, linear function enclothes whole application frequency almost paragraph. RF2132 is arsenic changes gallium heterogeneous knot parts of an apparatus (HBT) , can satisfy radio frequency circuit to be opposite well the requirement of enlarge power, efficiency and power supply voltage. Frequency of each chip job is 915MHz in this design. TRF6901 modulation means is OOK, this can pass register of will in-house B the 4th position 0 will come true. The REIN that TRF6901 wants place to send signal to bring a foot to send to MW4IC915 through PA cites a base, after undertaking to signal power magnifies, blast off by aerial go out; Aerial receives the signal that come to undertake to its through RF2132 linear signal magnifies, the LNA that TRF6901 enters later cites a base, undertake handling by date of collection of TRF6901 butt joint, finish read write implement the data of front exchanges the task. External interface module graph shows 2 times external interface module is n change-over circuit, main parts of an apparatus is ICL232. ICL232 chip is finished read write implement the changeover of in-house TTL n and RS-232 n, through join standard 9 needles string together mouth and exterior computer connection. It is a two-way RS-232 that accords with EIA RS-232 standard and V28 standard is sent, receive interface chip, the TTL/CMOS n of the responsible circuit that finish strings together the changeover of buccal n to the standard, the noise that can improve data to receive through lag is restrained. The L that cite a base and of 3 indirect capacitance of 1 μ F, cite a base 2 receive 5V power source through capacitance of 1 μ F, 3 bring a foot to form 5V n to the change-over circuit of 1OV n; Cite a base 4 with of 5 indirect capacitance of 1 μ F, cite a base 6 through ground connection of capacitance of L μ F, 3 bring a foot to form IOV n to - the change-over circuit of 10V n. If the graph is shown 3 times,control module controls module construction. Read write implement built-in control task basically is finished by W77E58 chip, it is compatible the 8 CMOS fast MCU of 8051. Compare with 8051 photographs, it reduced a machine to dictate executive time and memory are periodic, reduced power comsumption. It includes 32KB Flash EPROM, support does not have exterior memory component piece go up 1KBSRAM, managing more I/O cite a base. It is had 4 8 I/O port mix additional 4 I/O mouth and await condition to control signal, 3 16 time, tally, 12 two interrupt first step interrupt a source, two are strengthened model full duplex operation is serial communication port and but timer of process designing watchdog; Need oscillating circuit of adscititious restoration, crystal and power supply circuit only can. In this design, w77E58 job frequency is 40MHz. Its P1 mouth joins each TRF6901 control cite a base, the control that is over to send and receive chip in couples offers data to transmit place to need clock signal to wait; The data that strings together a 1 join TRF6901 sends and receive end, realize the serial communication of data. MCU strings together an ICL232 of 0 join chip, through asynchronous communication finishs data to transmit, want set W77E58 to string together a 1 job to be in only means L, the baud with choice and same computer is led can. This part design basically is centered in programming part, regard Pl mouth as common I/O mouth is used can. If the graph is shown 4 times,principle of circuit of module of management of power supply of module of power supply management pursues. LM317T is regulating unit of a 3 upright voltage, through changing the value of alterable resistor R6, can offer the power supply voltage of 1.2V ～ 37V. Offer IC load to cross electric protection at the same time. The input end of circuit of module of power supply management and output end all paralell connection agrees with the tantalum electric capacity that filter eliminates low frequency noise agrees with with filter divides high frequency noise alone stone capacitance, in order to improve the quality of power source. Software design is read write implement software design basically includes main program design and label to read write prevent conflict programming two parts.
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