Implementation of NFC on an ARM Cortex-M3 based
Contents
1. 13 CHAPTER 4 NFC MODULES 4 1 Comparison of NXP s modules NXP has two categories of NFC modules transceivers and controllers A comparison of the different modules can be studied in detail in table 4 1 on the next page The table summarizes the most parts that needs to be compared when choosing the NFC module The first part is about the interface that the module should be connected with UART 26 C 27 SPI 28 8 bit parallel 29 or USB 30 SWP is the single wire protocol 31 and it is used together with the secure element mentioned in section 3 1 on page 7 S C is also a special interface for the secure element but it uses two wires one for transmitting and one for receiving In many applications a more high level language i e C or Java is wanted this demands a CPU that can translate the commands to the NFC module NXP has included CPUs in three of the modules in table 4 1 on the next page The memories RAM ROM and E PROM are only available on the modules with a CPU The standards supported by the different modules diverge which standard that is wanted depend on the application The different standards is described in more detail in section 3 2 on page 8 FeliCa and MIFARE are Sony s respectively Philips NXP s own version of the ISO 14443 They are both used frequently in different ISO 14443 implementations ISO 15693 is the standard about vicinity cards this is a technology with a greater distance 1 1 5 m but2. al o al pay al N Closing communication link a a Ko InDataExchange end Link closed Or or or NOD ag Figure A 1 The output from the software on Midrange acting as initiator 58 OANDOTBWNH xxx NFC Protocol x x Length of ATR REQ 19 NFCID3i 11 22 33 44 55 66 77 88 99 AA 00 DiDi 00 BSi 00 BRi 02 PPi 4d InGeneralBytesLength 0x08 InGeneralBytes hex 4D 69 64 72 61 6E 67 65 InGeneralBytes char M i d r a n ge NADi 00 Number of bytes received from initiator is 4 NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 8 NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 12 NFC NFC NEC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 16 NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 20 NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 24 NFC NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 28 NFC NFC NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 32 NFC NFC NFC NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiato
3. structure can be found in figure 7 6 on page 41 7 5 An application for a charging pole for electrical Cars Syntronic have a charging pole for electrical cars in some test cities There are some functions included in the existing pole but Syntronic is developing the next generation of the pole In the next generation they might be interested of using NFC the most interesting function might be the ability to pay over NFC Today the payment and identification is done via RFID tag This has some drawbacks the payment credentials must be stored somewhere there is no possibility to lend out the car to the family or to friends and they can pay directly the payment details must be changed when they are updated and etcetera 36 7 6 GENERALISING THE CODE TAMPER key pressed PASSIVE mode ACTIVE mode TRUE Polling tags and return their ID Delay 2 s TAMPER key pressed FALSE TRUE TARGET mode INITIATOR mode Figure 7 4 A flowchart for the NFC mode selection in the main file The payment methods that the big card issuers are using are very complex and secure This would require a lot of studies in this methods and many of them might not be available to anyone The hardware for making the payment possible in the charging pole could be the same as in this project The software for the payment might be the best to obtain from a company that are specialised in payments or directly from the card issuers The fu
4. After discussed this with Syntronic we came to a solution where it really not matter which kind of data that was sent I should focus the implementation on making the code more generic and easy to understand which would help Syntronic more in the future For testing my code and communicate over NFC I had some tools three different passive tags and one desktop reader The problem with the desktop reader was that I could not use my own code for it I had to rely on someone else s code There was no possibility to flash the microprocessor on board without specific drivers it might be possible to use like the breakout board but it would also require unwritten drivers The best solution was to use the example code that the manufacturer of most of the NFC modules NXP provides for the desktop reader The example code was big and it would have required a lot of time to understand it I focused on some parts and made some small modifications of it to suit me better The other parts I relied on the interface that was included in the code The purpose was only to show that my code works for sending and receiving data over NFC It would have been interesting to be able and test my code communicating with another version of my code Now I did not have the resources that this required but I think that it would have worked In the project plan it was planned that at least eight hours per week was used for documentation throughout the project This has varie
5. NFC is not a new technology it has been prophesied for a long time The most common application for it is the payment application The problems that have been slowing down NFC from being well spread today is especially two The first is the trust issues 15 is the user willing to give out all its credentials Does the user rely on the cellphone manufacturer or the operator The security critical functions 7 CHAPTER 3 NFC IN GENERAL Tap information sign Pair with headset Check in at the airport Buy airplane tickets Exchange files or business card Pay and checkout hotel Figure 3 1 A typical flow over the usage of NFC need something called a secure element This is very similar to the existing SIM card in today s cellphones and can be implemented in both hardware and software The secure element leads into the next problem for the spreading of NFC who will own the secure element The operators will include it into the existing SIM cards the manufacturer also want to have control over the secure element but embedded in the phone Nowadays even more players want to act and own the secure element the credit debit card issuers and the manufacturer of the phone s operating system i e Google with its Android system These two problems are urgent to solve to enable the spread of NFC A solution might be on its way Google is such an innovative and big company and they have
6. 0x00 OxFF 0x00 OxFF 0x00 0x00 0x00 OxFF OxFF 0x00 0x00 a Acknowledge message b Negative acknowledge message Figure 6 4 Special messages for NXP PN532 29 CHAPTER 6 DETAILS ABOUT THE USED NFC MODULE Wakeup message To initialise and wakeup the NFC module a special wakeup message must be sent The module always starts in sleep mode and does not start correctly before it has received the wakeup sequence The wakeup sequence also configures the module with different modes The bytes in the wakeup sequence used in this project are depicted in figure 6 5 0x55 0x55 Ox00 Ox00 Ox00 Ox00 Ox00 OxFF 0x04 OxFC OxD4 0x14 0x01 0x01 0x16 0x00 Figure 6 5 The wakeup sequence for PN532 30 The implementation phase The implementation part was started a little bit early compared to the project plan since the hardware comparison was so dominant by NXP 7 1 Learning the platform The project has not developed anything on the Midrange platform before therefore it was required to learn the platform thoroughly before starting to write NFC specific code The platform can be implemented both with and without a real time operating system In this project it was chosen to use the one most common in Syntronic s projects with a version of FreeRTOS 38 running on the core Roughly two weeks were accumulated to learn the platform this process included the basics on the platform and in FreeRTOS Firstly the envir
7. 1 Bla V x 8 75 x 10 4 5 9 100 x 13 56 x 100 ee The antenna on the breakout board was not able to read a tag through the plate shield The same result was achieved with the desktop reader it was also unable read the tag 8 2 2 Aluminium foil wrapped cardboard 1 a y x 1 257 100 3 5 x 107 x 13 56 10 Ea ee 45 CHAPTER 8 RESULTS The chances for reading a tag through the cardboard wrapped with aluminium foil were better when just looking at the skin depth However none of the two antennas were able to read a tag through this shield 8 2 3 Thick plastic plate The skin depth for plastic is not applicable since plastic is an insulator If the properties of plastic is used in the skin depth equation the result will be an almost infinite skin depth compared to the two in equation 8 1 and 8 2 In reality the plastic shield disturbs the signal anyway The antenna on the breakout board was able to reach the tag through the plastic shield It was even possible to read a tag through two plastic shields which means a plastic shield with a thickness of 2 cm see figure 8 1 However the yield of polling the tag was reduced with the double plastic shield but it could still easily read a tag Figure 8 1 The double plastic shield The desktop reader was also able to read a tag through the plastic shield without any problems The antenna was though not powerful enough to reach through the double plastic shiel
8. X 0x92 158 TgGetData X 0x86 160 TgSetData X 0x8E 164 TgSetMetaData X 0x94 166 TgGetInitiatorComn X 0x88 168 TgResponseTolnitiat X 0x90 170 TgGetTargetStatus X 0x8A hy 64 TRITA ICT EX 2011 182 www kth se
9. a monopoly in the NFC world 22 However Broadcom by their acquisition of Innovision 23 Infineon 24 and Samsung has their modules in their starting blocks 25 In the beginning of the project the manufacturers of NFC was identified Quickly it was discovered that by focusing on readers NXP was the only choice of the NFC modules There is a lot of manufacturers of the tags that the readers and modules can interact with the market for this is much bigger and more shared between different companies Some microprocessor and software developers have tried to make the implementation of NFC easier by creating their own PCB The boards often host a microprocessor an antenna and a connection interface This is done as a service to other companies so that they can create NFC products more easily by integrating all needed parts in one PCB and a more high level programming language Most of these PCBs contains either of NXP s modules NXP has two kinds of NFC modules one kind is the NFC transceiver that only includes the NFC functionality the other kind is similar to the transceiver but it also hosts a microprocessor The microprocessor version is called NFC controller and the microprocessor on board is an 80C51 The NFC controllers are available on the PCBs mentioned before and these boards host dual microprocessors The additional microprocessor enables more high level programming and additional communication protocols compared to the NFC controller
10. and the intention was that it should be very easy to use The software written in this project is very easy to use and even to modify The performance of the breakout board was also good and the antenna on the board is recommended for most of the applications Today there is no indication for Syntronic to replace their RFID in the charging pole and use NFC instead The functionality that NFC would add to the pole compared to RFID is more security and the ability to send all kind of data The ability to pay over NFC in the pole was far too complicated to fit within this project Preface This thesis was the closure of a five year study period in Stockholm The years have been filled with a lot of fun and of course even more hard work The thesis is also the closure of for this time at least my 17 years of continuous work in school I will thank some important people for making this thesis possible to complete First I want to thank everyone at Syntronic for their hospitality support and kindness Joel Nilsson has been a fellow student for all my years in Stockholm and has also been a big support throughout this thesis The perhaps biggest support has come from my fianc e Ther se Olsson I hope that you will enjoy this report as much as I did when doing this thesis Have a nice reading Martin Axelsson Contents 1 Background Implementation of NFC on an ARM Cortex M3 based platform 1 1 2 History 21 2 3 IFF Identi
11. communication is not that rich of features and also not the scope for this thesis It was though a good and simple test for testing NFC for the first time OxD4 The byte indicating that the command is sent from the host 0x4A The command byte InListPassive Target MaxTg The maximum number of targets that should be initialised by PN532 The module can handle maximum two targets at once BrTy The wanted baudrate to be used the supported modes are e 0x00 106 kbps type A ISO 14443 Type A e 0x01 212 kbps FeliCa polling e 0x02 424 kbps FeliCa polling e 0x03 106 kbps type B ISO 14443 3B e 0x04 106 kbps Innovision Jewel tag InitiatorData Array of data that can be used during the initialisation Figure 7 3 The message sent to poll for passive devices 7 4 Talking to the computer from the platform over NFC The real scope for this project is to implement a solution that uses the active communication enabled by NFC The active communication involves more features compared to the passive one the possibilities are also much more with an active communication The passive communication almost only support the functions mentioned in section 7 3 on page 33 and the active communication have support for almost all kind of wireless communication However NFC is not useful in all kind of communication since the poor range and relatively small bandwidth The structure 35 CHAPTER 7 THE IMPLEMENTATION PHASE of the communica
12. do not have a sharp implementation where it should be used it is good to have as much free ports as possible available To enable more free ports UART was chosen it is also the most simple communication protocol available on the breakout board The NFC board require however not the usual UART connection it must be connected to the TTL level of the UART port The Midrange has also these ports available through the standard 0 1 inch connector so this was not a problem How the breakout board is connected to the platform is explained more in chapter 7 on page 31 22 5 4 ADDITIONAL HARDWARE AND TAGS DC USB LAN SD CARD Y F o Q e lg 2 3 Q RY 2 corte z z 5 te pe a a 7 o a S JTAG ian WKUP RESET TAMPER RS232_2 RS232_1 Figure 5 2 The Midrange platform 5 4 Additional hardware and tags The project needed more hardware than just the Midrange platform and the NFC breakout board to complete the tasks and to be able to show some results The additional hardware that was needed was both tags to be able to test the passive communication and another NFC device needed for testing the active communication The tags can be bought from almost everywhere and are also often cheap Another NFC device is harder to get for a reasonable price It exists cellphones with NFC compatibility but that should have been too expensive and also harder to control Therefore a desktop rea
13. page 23 there was three passive tags The tags were of three different types NFC Forum enabled NFC Forum Type 2 and Type 4 tag mentioned in section 5 4 on page 23 The three tags have different ID and length of the ID the embedded memory variates also among the three tags It is easier to start reading passive tags instead of active since passive tags normally just replies with its ID The other functions often used is read and write to the 33 CHAPTER 7 THE IMPLEMENTATION PHASE lt COM port gt NFC breakout board Figure 7 2 The setup used to debug the NFC commands embedded memory To be able to read the passive tags a polling request must be sent to the NFC module from the Midrange The polling request is easy if the host only need the information of which tag that is present The command sent to perform the polling is called InListPassiveTarget command byte 0x4A the full command is illustrated and explained in figure 7 3 on the facing page All other supported commands are listed in the appendix If the module finds any passive tags it gives it a short ID 0x01 to 0x02 that can be used instead of the full ID for a short period of time This is useful if the user wants to send a message to tag without using the full ID The PN532 also replies with the full ID and other 34 7 4 TALKING TO THE COMPUTER FROM THE PLATFORM OVER NFC bytes stored in the ID block on the passive tags to the host The passive type of
14. the project s soft ware 57 B Supported functions by PN532 63 List of Figures 3 1 4 1 9 1 5 2 5 3 5 4 6 1 6 2 6 3 6 4 6 5 7 1 7 2 7 3 7 4 7 5 7 6 T T 8 1 A typical flow over the usage of NFC The NFC module PN5382 lt 2 gic da ara dt e oad The NFC breakout board sae a ha ee The Midrange platform data aia E es eee ae ad The contents of the NFC kit delivered by SCM Microsystems All hardware used in this project for active communication The form that the normal commuication follows The beginning of all messages The message suciedad al o Special messages for NXP PN532 o o The wakeup sequence for PNB32 0 The beginning of the main file The setup used to debug the NFC commands The message sent to poll for passive devices A flowchart for the NFC mode selection in the main file A flowchart for the NFC target mode A flowchart for the NFC initiator mode The three tested shields for the antenna test The double plastic shield o sata ek A ok SR EO Ye aS LIST OF FIGURES vi 9 1 The two NFC boards on top of each other 50 A 1 The output from the software on Midrange acting as initiator 58 A 2 The output from NXP s software acting as target 59 A 3 The output from N
15. the reader The microprocessor also hosts a memory where the card s encrypted details are stored these are used instead of the old magnetic stripe Smart cards have also evolved and today it exists contactless smart cards 14 They work as regular smart cards but wirelessly over a very short range Smart cards and NFC has been tight coupled in the technological evolution In fact one can say that RFID and smart cards has been combined into NFC The security functions in security critical implementations of NFC are the most visible heritage from smart cards NFC in general NFC will most likely be very common in a quite near future As mentioned in chapter 1 on page 1 all major cellphone manufacturer have almost promised to release cellphones equipped with NFC hardware NFC will probably replace today s payment methods sometime in the future The payments is not the only upcoming implementations of NFC The idea from mainly the cellphone manufacturer area is that NFC will enable more convenient and additional services All services will be included in the cellphone that every user will have a realistic flow in the future is illustrated in figure 3 1 on the next page The flow can be a business trip or similar The NFC device can be used to pay with as a passport instead of tickets to get more information at a information poster to easily pair a wireless headset and to exchange all kind of data between two devices 3 1 NFC payments
16. 6x6 4 5x4 5 Package type HV HV HV HV HV TF QFN32 QFN32 QFN40 QFN40 QFN40 BGA64 HV HV QFN40 QFN40 Cost Less Less Less Less Less Less than 5 than 5 than 9 than 15 than 15 than 11 4 2 Conclusion and decision of the NFC module in this project The purpose of this project is to create and show a prototype where NFC should be involved Since the prototype should be broad the module should have as much possibilities as possible The broadness of the project has also made that there are no demands on the cost unit or the power consumption All modules are also in perspective cheap and consume very little power The requirement on the module is consequently that it should at least have the most popular standards within 17 CHAPTER 4 NFC MODULES the NFC area The modules named PN512 PN532 PN533 and PN544 all have ISO 14443 A B ISO 18092 MIFARE and FeliCa These four modules answer the requirements of the most popular standards In this project the NFC module should be connected to a Cortex M3 processor which has many communication interfaces and is more described in section 5 2 on page 21 both kind of modules can therefore be used The microprocessor available in some of the modules enables a more high level of communication between the module and the Cortex this is desirable for this project The project will use the programming language C to do the programming and for this a module with a CPU is needed The mo
17. E ACTIVE INITIATOR mode selected Set ID and general bytes for PN532 Poll for ACTIVE TARGETS FALSE RUE Establish link Link established FALSE TRUE Send i x NFC i gt number_of_messages Increment i TRUE e n d received FALSE TRUE Link closed Figure 7 6 A flowchart for the NFC initiator mode 41 CHAPTER 7 THE IMPLEMENTATION PHASE a The plastic shield compared to a regular USB b The aluminium foil shield connector c The shield made of some kind of plate Figure 7 7 The three tested shields for the antenna test 42 Results The results in this project are few the main purpose for the project was to deliver a building block for NFC on the Midrange platform The project has accomplished to deliver this on time 8 1 Software The different software works well together The only small problem is the establish ment of the connection If the devices not find each other directly the connection will fail The problem is mainly in the NXP software it polls for devices only for a few times and then exits if no device was found 8 1 1 The software on Midrange The software running on the Midrange platform asks in the beginning the user which mode that should be executed The different modes are passive and active where active can be as the initiator or as the target The output from the software can be seen in Appendix A on pa
18. Implementation of NFC on an ARM Cortex M3 Based Platform a ES o MARTIN AXELSSON KTHAS 9 9 SES KTH Information and Communication Technology Degree project in Communication Systems Second level 30 0 HEC Stockholm Sweden Gp Gane KTHY VETENSKAP e OCH KONST YE Sy ge KTH Information and Communication Technology Implementation of NFC on an ARM Cortex M3 based platform Degree project in electronic and computer systems second level Martin Axelsson Stockholm 2011 10 21 Abstract Syntronic a medium sized company in Sweden has a multi purpose platform Midrange that is used in many projects The library for the platform is solid but can be even bigger This project will evaluate if NFC is a good solution for one of their biggest applications for Midrange a charging pole for electrical cars The second and main task is to create a good set of NFC functions that can be added to the library To be able to create and test the functions and the possibilities a set of hardware are needed The hardware should be evaluated chosen bought and tested within the project The Midrange platform was connected to a breakout board for NFC The board hosted a module from NXP PN532 The breakout board was connected via RS 232 to the platform after considering different interfaces After learning the functions of the platform it was time to start writing the NFC library The library was written as an API
19. TgSetData Continuing TgGetData ABCDEFGHI TgSetData TgGetData ABCDEFGHIJ TgSetData TgGetData Closing communication link Figure A 4 The output from the software on Midrange acting as target 61 62 Supported functions by PN532 The commands in table B 1 are all the commands that are supported by NXP s NFC module PN532 Each command is explained in detail in the manual for PN532 45 Table B 1 All commands supported by NXP s PN532 Diagnose X X 0x00 69 GetFirmwareVersion X X 0x02 73 GetGeneralStatus X X 0x04 TA ReadRegister X X 0x06 76 WriteRegister X X 0x08 78 ReadGPIO X X 0x0C 79 WriteGPIO x x 0x0E 81 SetSerialBaudRate X x 0x10 83 SetParameters X X 0x12 85 SAMConfiguration X X 0x14 89 PowerDown X X 0x16 98 RFConfiguration X X 0x32 101 RFRegulationTest X X 0x58 107 Continued on next page 63 APPENDIX B SUPPORTED FUNCTIONS BY PN532 Table B 1 All commands supported by NXP s PN532 continued InJumpForDEP X 0x56 108 InJumpForPSL X 0x46 113 InListPassiveTarget X 0x4A 115 InATR X 0x50 122 InPSL X 0x4E 125 InDataExchange x 0x40 127 InCommunicateThry X 0x42 136 InDeselect X 0x44 139 InRelease X 0x52 140 InSelect X 0x54 141 InAutoPoll X 0x60 144 TgInit AsTarget X 0x8C 151 TgSetGeneralBytes
20. XP s software acting as initiator 60 A 4 The output from the software on Midrange acting as target 61 List of Tables 3 1 4 1 4 1 4 1 6 1 8 1 B 1 B 1 Comparison of NFC s competitors o 10 NX Bis NEC m dules eat o el ee ea 15 NXP s NFC modules continued 2552424544825 e 16 NXP s NFC modules continued 20 4 ac eh ayes a 17 Description of the words used in the message structure 28 Implemented functions oe o a Ee 44 All commands supported by NXP s PN532 63 All commands supported by NXP s PN532 continued 64 vil viii Backeround Near Field Communication or NFC 1 is a technology with a most likely bright future It is said that NFC should move the daily life to the next level by enabling the Internet of things 2 NFC is a multi purpose technology the most common usages are payments tickets and identification Recently in the Mobile World Congress 2011 in Barcelona NFC was one of the big trends in the mobile world in the near future 3 NFC has been included in mobiles earlier especially in the Asia region but it is just recently that almost all major manufacturers claims that they will include it in the most of their upcoming phones 4 1 1 Implementation of NFC on an ARM Cortex M3 based platform In this project NFC should be included and implemented on an existing platform that is provided by Syntronic 5 in Sweden The platfo
21. akes off GfK TechTalk 2011 07 28 7 A Hardy Google to begin test of nfc payment system in new york san francisco android headlines http androidheadlines com 2011 03 google to begin test of nfe payment system in new york san francisco html Android Headlines 2011 07 28 8 Iso about iso http www iso org iso about htm ISO 2011 07 28 9 K Finkenzeller RFID Handbook 3rd ed John Wiley Sons Ltd 2010 9 Near field communication nfc http www ecma international org activities Communications 2004ga 067 pdf ECMA 2011 07 28 9 Near field communication interface and protocol 2 nfcip 2 http www BIBLIOGRAPHY ecma international org publications files ECMA ST ECMA 352 pdf ECMA International 9 21 Near field communication wikipedia the free encyclopedia http en wikipedia org wiki Near_ Field Communication Wikimedia Foundation 2011 07 28 10 22 D Balaban Vendor group seeks to crack mifare dominance nfc times new near field communication and all contactless technology http www nfctimes com report vendor group seeks crack mifare dominance NFC Times 2011 07 28 13 23 Broadcom announces intention to acquire innovision research technology plc http www broadcom com press release php id s480684 Broadcom Corporation 2011 07 28 13 24 Infineon s embedded secure element brings security to nfc enabled smart phones infineon has l
22. applications e Make recommendations regarding both software and hardware in upcoming projects History Near field communication has evolved from several other technologies the nearest cousins are RFID and Smart card 2 1 IFF Identification Friend or Foe The Germans was first with developing an IFF system 8 during the World War II their version was very simple but not so reliable The system was used to identify if incoming airplanes was a friend or a foe and used only existing radar technology The German planes modified the backscattered radar signal by rolling the plane this changed the polarisation of the signal and enabled identification of the planes by the radar operator This worked well in the beginning but was eventually discovered by the enemies The British air force invented a similar version to the German s IFF they placed active transponders on each of their plane The active transponder used the radiated radar signal and sent a modulated signal back The active transponder made a more distant identification possible but the first version needed a mechanically tuning of the frequency used by the different radar frequencies The British IFF system evolved during the war and made it possible for the British forces to apply 3 CHAPTER 2 HISTORY up to six different codes to the modulation later in the war The different modes provided additional information about the plane to the ground station So
23. as ten pins To mount PN532 on a board by hand would be very difficult which could be obvious by looking at picture 4 1 on the facing page The module require an antenna to be able to read tags and other devices the antenna is not included in the package NXP provides documentation on how 18 4 2 CONCLUSION AND DECISION OF THE NFC MODULE IN THIS PROJECT to both dimension and match the antenna To avoid both mounting the module by hand and making an own antenna a breakout board from microBuilder eu 33 was chosen The breakout board is also much cheaper than to order an own board from a PCB manufacturer and it can be delivered directly Now the project had the possibility to create a very cheap board at KTH but then the module needed to be soldered by hand The solution with the breakout board seemed to be perfect for this project since it is only a test and an evaluation of NFC that should be created in a short period of time Figure 4 1 The NFC module PN532 19 20 The hardware used in this project 5 1 NFC hardware The hardware chosen to implement Near Field Communication in this project is as mentioned in section 4 2 on page 17 a board from microBuilder eu The board is developed to be used in small and simple projects The purpose is that small projects and even for private usages quickly can get started with an open source hardware that is manufactured in the most cost effective way The board hosts everything ne
24. cyclopedia http en wikipedia org wiki Intel_ Pentium_ 4 Wikimedia Foundation 2011 07 28 31 43 Windows xp wikipedia the free encyclopedia http en wikipedia org wiki Windows xp Wikimedia Foundation 2011 07 28 31 44 Development and prototype boards and tools for pic avr and msp430 http olimex com dev index html OLIMEX Ltd 2011 07 28 31 45 Pn532 user manual http www nxp com documents user_ manual 141520 pdf NXP Semiconductors 11 2007 63 59 56 Outputs from both NXP s software and from the project s software APPENDIX A OUTPUTS FROM BOTH NXP S SOFTWARE AND FROM THE PROJECT S SOFTWARE Starting Initialize NFC DONE SAMConfiguration ANownhwnre GetFirmwareVersion Version PN532 Firmware 1 6 Support 7 ho row m N Hf w Press key for active NFC mode ACTIVE release for TARGET INITIATOR Pee ane j J InJumpForDEP 00 01 01 02 03 NNNNDNRRA 5 0w0N Oo0Do CO More identification bytes N al 6D 20 4E 58 50 CD WWwWwnnnwyv NrCOCAND w w w R InDataExchange w al w aD w InDataExchange NFC w 00 w No IS H E 41 InDataExchange NFC NFC E H R w IN H IN InDataExchange 46 NFC NFC NFC H AS E H NN InDataExchange NFC NFC NFC NFC H
25. d http www microbuilder eu Projects PN532 aspx MicroBuilder SARL 2011 07 28 19 34 Tx systems inc development tools https www txsystems com devtools php scmnfcdemokit Tx Systems Inc 2011 07 28 23 35 Nfe forum Technical specifications http www nfe forum org specs spec _ list NEC Forum 2011 07 28 24 36 Pn532 c1 nfc controller from nxp semiconductors http www nxp com pip pip pip 120112 pp t pip i 120112 NXP Semiconductors 2011 07 28 24 37 R Conty download libnfc org public platform independent near field communication nfc library http www libnfc org download libnfc org 2011 07 28 24 38 Freertos a free professional grade rtos supporting 27 architectures including arm7 arm9 cortex m3 rx600 msp430 msp430x microblaze avr x86 pic32 pic24 dspic h8s hesl2 and 8051 http www freertos org Real Time Engineers Ltd 2011 07 28 31 39 Eclipse the eclipse foundation open source community website http www eclipse org The Eclipse Foundation 2011 07 28 31 40 Eclipse packages eclipse packages http www eclipse org downloads packages release ganymede r The Eclipse Foundation 2011 07 28 31 54 BIBLIOGRAPHY 41 Sourcery g lite 2009q1 203 for arm gnu linux http www codesourcery com sgpp lite arm portal release858 Mentor Graphics 2011 07 28 31 42 Pentium 4 wikipedia the free en
26. d a lot during the project in the beginning and in the end the documentation part has been bigger and the implementation part bigger in between It was maybe somewhat overambitious to think that it was possible to document that much each week but even if the documentation part has been smaller it was a great help in the end 48 9 2 FURTHER WORK AND RECOMMENDATIONS 9 2 Further work and recommendations The code written in this project is not written against any specific implementation and it is intended by the project to be that way The code is generic and should without any big changes be able to use in a small project It is also easy to understand and to use well commented follows a good structure and all variables and functions have logical names For small projects the code can be used as it is written now For bigger projects it might require some changes adapted to which kind and amount of data to be sent For using the passive version it is only implemented the ability to read a tag s ID Since the scope for this project was the active NFC it is not implemented the possibility to read and write to the memory on a passive tag This could easily be done by a person that know some software since all hardware is there and it is well described in the manual for the NFC module The antenna is the most important thing when considering the hardware First of all it should be properly matched so it get the maximum performance for
27. d at all 46 Conclusions and further work The project was successful both by looking on the implementation and on the planning There were some small changes compared to the first plan but nothing that was essential 9 1 Conclusions I think this project has been worthwhile I have had a big interest for NFC and RFID for a long time It was also interesting to do a project on such a promising technology as NFC is There were some changes in this project compared to the project plan that was established in the beginning The biggest change was that the implementation is not mainly written against the charging pole for electrical cars It is fully possible to use it in that implementation but the code is not written against it Therefore some other changes was done due to the switch the simulation of payment was cancelled and also the possibility to pay with NFC at the charging pole Regarding the payment simulation the implementation would have been very difficult and not that worth spending time on It would have demanded a huge project just to get into how real payments through banks is done and a lot of meetings with big and 47 CHAPTER 9 CONCLUSIONS AND FURTHER WORK slow actors on that market It would possible to do this but it would yield at least one master thesis in my opinion When the implementation against the charging pole was cancelled there was some discussions of which kind of data I should send over NFC
28. der seemed to be the best choice for this project A kit from SCM Microsystems 34 was found it included a desktop 23 CHAPTER 5 THE HARDWARE USED IN THIS PROJECT reader and three different tags for just 39 95 and is depicted in figure 5 3 The tags were of NFC Forum Type 1 2 and 4 35 and manufactured by SCM The desktop reader sported a NXP PN531 module this made it possible to use SCM s NXP s 36 or libNFC s software 37 SCM s free software included only the feature to read the tag and then open the website stored on the tag all through a simple GUI LibNFC is an open source software that provide a library for many NFC functions The library is not developed by a company and the support for it is not the best NXP s software is the easiest to use together with the desktop reader in the kit from SCM The source code for the software is also available if the user want to modify it a The three tags included in the NFC kit b The desktop reader SCM s SCL3710 Figure 5 3 The contents of the NFC kit delivered by SCM Microsystems 24 5 4 ADDITIONAL HARDWARE AND TAGS Figure 5 4 All hardware used in this project for active communication 25 26 Details about the used NFC module The best module for this project was NXP s PN532 which was superior the other modules found in chapter 4 on page 13 There was a quick review of PN532 in chapter 4 on page 13 but in this chapter there will be more d
29. dules that meet both the requirements so far are all of these mentioned above except PN511 and PN512 When it comes to the communication protocols available on the three modules that still are an option there are some differences In PN533 NXP has focused on implementing USB this module has neither I C nor SPI The platform used in this project has the possibility to use an USB connection but the other serial interfaces are more preferable The single USB connection on the platform is used in many other applications therefore any other connection is more preferable With that choice the available modules are only two PN532 and PN544 The differences of the two modules are small PN544 has a different microprocessor from the same family supports ISO 15693 and has more security functions ISO 15693 which also is called vicinity card and described shortly in section 4 1 on page 14 is not a target for this project and the feature is hence not requested in this project The project should also not implement any advance security functions and therefore the additional security functions in PN544 are not needed All this leads to the conclusion that the PN532 is the best option for this project PN532 and all other PN5XX devices from NXP is made to be embedded in small and mobile devices The module has an area of six by six mm the module hosts on this area 40 pins All pins are placed on each edge of the squared package which means that each side h
30. eading position in security chips for nfc enabled smart phones infineon technologies http www infineon com cms en corporate press news releases 2011 INFCCS201105 048 html Infineon Technologies AG 2011 07 28 13 25 news samsung http www samsung com us news newsRead do news _ seq 19759 SAMSUNG 2011 07 28 13 26 Universal asynchronous receiver transmitter wikipedia the free encyclope dia http en wikipedia org wiki Uart Wikimedia Foundation 2011 07 28 14 27 I2c wikipedia the free encyclopedia http en wikipedia org wiki I2c Wikimedia Foundation 2011 07 28 14 28 Serial peripheral interface bus wikipedia the free encyclopedia http en wikipedia org wiki Serial_ Peripheral_Interface_ Bus Wikimedia Foundation 2011 07 28 14 29 Parallel communication wikipedia the free encyclopedia http en 93 BIBLIOGRAPHY wikipedia org wiki Parallel_ communication Wikimedia Foundation 2011 07 29 14 30 Usb wikipedia the free encyclopedia http en wikipedia org wiki USB Wikimedia Foundation 2011 07 29 14 31 Single wire protocol wikipedia the free encyclopedia http en wikipedia org wiki Single_Wire_Protocol Wikimedia Foundation 2011 07 28 14 32 Findchips com online electronic component distributor inventory search http www findchips com SupplyFrame Inc 2011 07 28 15 33 Pn532 nfc breakout boar
31. ecksum the sum of D DIR DCS 0x00 POST Postamble message ended 6 1 1 Sending messages The PN532 cannot send anything to the host by its own responsibility it can only reply to commands that the host sends to it To send a message to PN532 the host 28 6 1 NFC MESSAGE PASSING should follow the structure in figure 6 1 on page 27 and 6 3 on the preceding page It is also important to listen for the acknowledge message after a sent message since it indicates if PN532 successfully understood the command 6 1 2 Receiving messages When the module replies to the host it modifies the command byte by adding the value 0x01 to the command code Therefore all command codes from the host to PN532 are even and all replies from PN532 are odd After receiving a correct message the host can optionally send an acknowledge message A negative acknowledge after a received message leads to a retransmission of the last message from PN532 6 1 3 Special messages The NXP PN532 has some special messages that not follows the regular structure described in figure 6 3 on the facing page ACK and NACK For PN532 it exist two special messages acknowledge and negative acknowledge messages used as a handshake mechanism between the host and the module Acknowledge is used as positive handshake and negative acknowledge as a nega tive handshake A NACK message always lead to a retransmission of the latest message 0x00
32. eded to get started with NFC It has several connection protocols UART SPI and I C The antenna needed to read tags and to communicate with other NFC devices is also integrated in the PCB The connections on the board is easy to connect to by using standard 0 1 inch header pins The board can be examined in picture 5 1 on the following page below 5 2 Platform The platform used in this project is a platform developed within Syntronic The platform was developed to be used in projects where both performance and cost are on a medium level therefore the platform is called Midrange The Midrange is 21 CHAPTER 5 THE HARDWARE USED IN THIS PROJECT Figure 5 1 The NFC breakout board built around an ARM Cortex M3 processor and the connections on the board has several communication protocols UART RS232 CAN PC SPI USB Ethernet and RS485 see figure 5 2 on the next page The Midrange is well suited in many projects because its versatile functionality combined with the short start up phase Therefore it is extra well suited for projects in the medium level that should be finished within a short period of time 5 3 Connecting the hardware The Midrange is as mentioned in the previous section versatile when it comes to the communication protocols The breakout board with the module from NXP has also several communication protocols UART SPI and I C The Midrange has several ports that are implementing UART since this project
33. el interface or USB Together with Midrange I think the best interface is UART therefore the code is written for UART However it would not be any big changes if any of the other serial interfaces were used The breakout board has a connection to the interrupt pin on PN532 the pin can be used to trigger an interrupt on the host when a message is available I did not manage to get this function to work The pin is always connected to ground and therefore never trigger the interrupt on Midrange I had tried to setup the module right but something is wrong in the hardware or software for the module 50 Bibliography 1 NFC Forum About NFC http www nfc forum org aboutnfc NFC Forum 2011 01 19 1 2 NFC Enabling Mobile Payments the Internet of Things and the Next Wave of Applications BostInnovation Boston Innovation and Tech News Blog http www nfc forum org aboutnfe BostInnovation 2011 01 27 1 3 Avista time i barcelona p mobile world congress 2011 avista news https www avistatime com avista swe getNews 281 Avista Time AB 2011 07 27 1 4 Sony ericsson jumps onto nfc bandwagon Sgen trepreneurs http sgentrepreneurs com news stop 2011 07 27 sony ericsson jumps onto nfc bandwagon SGEntrepreneurs 2011 07 27 1 5 About us Syntronic http www syntronic se about Syntronic AB 2011 01 19 1 6 Cortex M3 Processor ARM http www arm com product
34. etails about it 6 1 NFC message passing The message passing has a predetermined structure where some parts are defined by the NFC standards and others by NXP It also follows a specific form this form can be seen in figure 6 1 Host PN532 Command Acknowledge Response Figure 6 1 The form that the normal commuication follows All messages start with a preamble consisting of a byte with zeros then a command 27 CHAPTER 6 DETAILS ABOUT THE USED NFC MODULE start code consisting of a byte of zeros and a byte of ones are following The structure for the beginning of the messages can be seen in figure 6 2 0x00 0x00 OxFF Preamble Command start Figure 6 2 The beginning of all messages All elements of the messages are divided in bytes and also all commands are represented by one byte The full structure is depicted in figure 6 3 and explained in table 6 1 Pac smar ster ten ics om com oo Figure 6 3 The message structure Table 6 1 Description of the words used in the message structure PRE Preamble START Command start START Command start LEN Length of data number of bytes in D COM DCS LCS Length checksum LEN LCS 0x00 DIR Direction 0xD4 Host to module 0xD5 Module to host COM Command one byte with the command code D Data array the array of data divided in bytes DCS Data ch
35. fication Friend or Foe ooa aa a 2 2 RFID Radio Frequency IDentification Smart card 3 NFC in general 3 1 3 2 3 3 NFC payments The standards NFC competitors 4 NFC modules 4 1 Comparison of NXP s modules 4 2 Conclusion and decision of the NFC module in this project 5 The hardware used in this project 5 1 5 2 5 3 5 4 NFC hardware Platform Connecting the hardware Additional hardware and tags 10 13 14 17 21 21 21 22 23 111 CONTENTS 6 Details about the used NFC module 27 6 1 NFC message passing e eee 27 7 The implementation phase 31 7 1 Learning the platform eel A ts Gee ele Ged 31 7 2 Start to talk to the NFC breakout board 32 7 3 Reading passive tags with the Midrange platform 33 7 4 Talking to the computer from the platform over NFC 35 7 5 An application for a charging pole for electrical cars 2 36 7 6 Generalising the code asia e a 6 4 kd AD ees 37 7 7 Measuring antenna performance o o 39 8 Results 43 Bel SOL WALES tr A E EA SS a a Wei ee A 43 8 2 Antenna performance s nap dr hs ed Bh ed we ek te 45 9 Conclusions and further work 47 O GORC INSIONS a si lia E a AS a eee 47 9 2 Further work and recommendations 49 Bibliography 51 Appendices A Outputs from both NXP s software and from
36. ge 57 and the implemented functions with a short description can be found in table 8 1 on the following page 43 CHAPTER 8 RESULTS Table 8 1 Implemented functions NFC_interpreter Interprets a received message both command and data NFC_send_ack Sends an acknowledge message NFC_send_nack Sends a negative acknowledge message NFC get_ firmware Returns the firmware version of the NFC mod ule NFC_send_command Sends a specific command NFC_send_data Sends data 1 256 bytes takes care of every thing regarding the send procedure NFC_receive_data Receives and presents any kind of data NFC_command_start Adds the beginning of each message NFC_command_end Adds the ending of each message NFC_ valid_ checksum Validates the checksum of a message NFC_ calc_ checksum Calculates the checksum for a message NFC_sum_of data Accumulates the value of each byte of data NFC_ valid_datd_checksum Validates the data checksum NFC_calc_data_checksum Calculates the data checksum NFC_check_beginning Validates the beginning of each message NFC_check_ack_nack Validates if a received message is a positive or negative acknowledge NFC_ check command Validates the received command in a message 8 1 2 The software on the desktop reader The desktop reader was used together with a slightly modified version of NXP s example code The
37. ictly limited power supply The cost is if possible for just one module if the order is big the price difference between each module is very small The price is fetched from a price comparing site 32 and the availability has not been considered Table 4 1 NXP s NFC modules NFC Transceivers NFC Controllers Operating distance Up to 100 depending on mode coil typical mm UART Mbit s Up to Up to Up to Up to Up to 0 4608 1 228 1 228 1 228 1 228 1 228 T C interface bit s 400 k 400 k 400k 400 k 400 k 3 4 M 3 4 M 3 4 M SPI interface up to 5 up to 5 up to 5 up to 5 8 Mbit s 8 bits parallel inter yes only yes only face QFN40 QFN40 USB 2 0 full speed no no yes no yes no interface SWP interface yes S C interface yes yes yes yes yes yes CPU no no 80C51 80C51 80C51 HT80C51 MX RAM ROM E PROM 1 k 32 1 k 40 1 2 k 44 5 k 128 bytes k k k k 52 k Continued on next page 15 CHAPTER 4 NFC MODULES Table 4 1 NXP s NFC modules continued Carrier MHz frequency card controller ISO 18092 peer to yes yes yes yes yes yes peer active passive ISO 14443 A read yes yes yes yes yes yes er writer ISO 14443 B read no yes no yes yes yes er writer FeliCa reader writer yes yes yes yes yes yes ISO 15693 read no no no no no yes er writer Card e
38. its size The size of the antenna determines how far the antenna can reach the range difference for the antennas used in this project can be found in section 8 2 on page 45 This would not matter that much if there is nothing in between the antenna and the target but if the antenna should be embedded in an enclosure it is important I have not made any of the two antennas I have tested therefore I do not know how well they are matched The bigger antenna on the breakout board I have never experienced any problems with For the smaller one on the desktop reader I had some unknown difficulties with these problems might be because of the antenna On the other hand in my tests they almost performed the same If size is critical I would recommend a smaller antenna like the one in the desktop reader if not I think it is more reliable to use an antenna like the one in the breakout board The area difference of the antennas is extensive the area of the antenna of the breakout board is more than eight times the one in the desktop reader which can be seen in figure 9 1 on the following page NXP which is the biggest manufacturer of NFC modules has modules with different communication interfaces The module used in this project PN532 sports UART 49 CHAPTER 9 CONCLUSIONS AND FURTHER WORK Figure 9 1 The two NFC boards on top of each other I C and SPI NXP has other modules that could be used instead they have support for a parall
39. just decided to not care about the operators or the card issuers Several especial payment tests is ongoing right now but Google has the biggest test They have launched tests in New York City and San Francisco but will later expand it to more cities 16 3 2 The standards NFC is such an evolving and prophesied technology and therefore a lot of standards are created by several standardisation organisations In this report the focus is 3 2 THE STANDARDS on the standards defined by the International Organization for Standardization ISO 17 3 2 1 ISO 14443 ISO 14443 18 defines the standard for contactless integrated circuit cards or proximity cards It is the evolution of the regular smart cards this version works without any contact but with a very short range ISO 14443 has also some minor standardisations under its name e g 14443 A 14443 B ISO 14443 is in fact not a special NFC standard but NFC started with the contactless smart cards that is described in this standard Since ISO 14448 defines the contactless smart cards it includes the wireless communication such as RF protocol Many NFC devices can imitate ISO 14443 by emulating the card the reader then determine the NFC device as a contactless smart card The purpose for this is that NFC devices could in the future store all kind of cards in the same device 3 2 2 ISO 18092 ISO 18092 19 is the first standard written especially for NFC It covers the mo
40. me has speculated that a better IFF system in Pearl Harbor could have prevented the catastrophic events in 1941 A radar station near Pearl Harbor identified the incoming planes but dismissed them as Americans 8 The IFF systems are still used but are far more complicated nowadays However IFF is the ancestor to NFC 2 2 RFID Radio Frequency IDentification RFID 9 was developed from the IFF system and it has been prophesied to be one of the most important technologies in our modern world for a long time The technology has not taken off as early as experts thought nowadays it is not even as popular as they expected RFID uses radio in different frequencies to mainly identify objects From the beginning of the 90 s RFID was meant to in a near future to replace the bar codes used everywhere 10 as one can discover even now this has not happened yet That is just another failure of the plans for RFID 11 but it will however probably replace the bar codes someday The RFID technology has as mentioned before different frequencies that is chosen depending of the intended implementation RFID needs two components to work one reader and one transponder The transponder is different depending on the usage as well it can be passive active or even printed on paper 12 and is referred to as a tag The frequency range is from 125 KHz to 5 8 GHz the lower frequencies often uses inductive coupling and the higher ones often using radia
41. mulation FeliCa FeliCa FeliCa FeliCa FeliCa FeliCa 15014443 15014443 15014443 15014443 15014443 15014443 A MEA ME A MEJA MIEJ A MI A B B FARE FARE FARE FARE FARE MI FARE NFC baudrate 106 212 106 212 106 212 106 212 106 212 106 212 kbit s 424 424 424 424 424 424 848 MIFARE classic yes yes yes yes yes yes Interface to smart SC S C sc S 820 S C SWP ply Embedded firmware no no yes yes yes yes Integrated LDO volt no no no yes no yes age regulator Low battery mode no no no yes no yes Battery off mode no no no no no yes Supply voltage V 2 5 3 6 Be Daa d3 0 2 5 4 0 Dodd PD SO SONO Min host interface 1 6 1 6 1 6 1 6 1 6 1 65 1 95 voltage V USB bus power sup 4 2 5 9 4 2 5 9 Continued on next page 4 2 CONCLUSION AND DECISION OF THE NFC MODULE IN THIS PROJECT Table 4 1 NXP s NFC modules continued Supply voltage for no no yes yes yes yes secure element inte grated Power down mode 5 5 10 5 12 3 typical uA Power down mode 10 10 30 25 30 50 with RF level detec tor on uA Transmitter supply 60 60 60 60 60 60 current typical mA Temperature range 25 85 25 485 25 485 25 485 25 85 25 85 C Package thickness 0 85 0 85 0 85 0 85 0 85 0 8 mm Package size mm 5x5 6x6 5x5 6x6 6x6 6x6
42. nctions written in the software is able to use for payments if one knows what data are needed to be sent to pursue the payment The code is also able to replace the existing RFID solution in the charging pole 7 6 Generalising the code By implementing and testing the active communication almost all important features of NFC was implemented Syntronic might have an application for NFC but it will be evaluated first They think like many others that it will be widely used in the future The purpose for them is to have a solid library for NFC functions 37 CHAPTER 7 THE IMPLEMENTATION PHASE ACTIVE TARGET mode selected Set ID and general bytes for PN532 Initialise as TARGET TRUE FALSE Link established TRUE Receive data from initiator te n yd Send e n d and TRUE close the link FALSE Send NFC from Syntronic Figure 7 5 A flowchart for the NFC target mode Try to init again ready and tested which could be easily embedded in any application Therefore it is a need of good and general functions in the code The functions should smoothly be included in any kind of application and be able to send any kind of data The code should also be simple to understand by using logical names on functions and variables This could be very useful for a user that do not have sufficient time to gain enough insight into NFC The user could read this report or use other sources to gain sufficien
43. ndBuffer for next iteration a priori SendLength 8 Index 0 ReceiveLength 4000 Receivelndex a posteriori SendLength 8 Index O ReceiveLength 18 Receivelndex Iteration 3 Transceive done Total Response Data Received from Target 18 NFC from Syntronic Add 1 bytes to SendBuffer for next iteration a priori SendLength 9 Index 0 ReceiveLength 4000 Receivelndex a posteriori SendLength 9 Index O ReceiveLength 18 Receivelndex Iteration 2 Transceive done Total Response Data Received from Target 18 NFC from Syntronic Add 1 bytes to SendBuffer for next iteration a priori SendLength 10 Index 0 ReceiveLength 4000 Receivelndex a posteriori SendLength 10 Index 0 ReceiveLength 18 Receivelndex Iteration 1 Transceive done Total Response Data Received from Target 18 NFC from Syntronic 6 d 1 bytes to SendBuffer for next iteration Send last data packet end gt end OK gt disconnect OK Figure A 3 The output from NXP s software acting as initiator VD0J OOCOAaANA Starting Initialize NFC DONE SAMConfiguration GetFirmwareVersion Version PN532 Firmware 1 6 Support 7 Press key for active NFC mode ACTIVE release for TARGET TARGET TgGetTargetStatus 01 22 7D A5 Link established TgGetData A TgSetData TgGetData AB TgSetData TgGetData ABC
44. onment needed to be setup it used the standard development environment Eclipse 39 the version was Ganymede 40 and the debugger was Sourcery G Lite 2009q1 203 for ARM 41 The environment was runned on an Intel P4 machine 42 with Windows XP 43 The Midrange uses a standard USB port to power the platform an external power supply can also be used and a JTAG 44 to flash the core with new software The debugger OpenOCD debugger 44 was the hardest part to get running in the beginning the combination of the JTAG and the configuration of Eclipse were 31 CHAPTER 7 THE IMPLEMENTATION PHASE hard to get right When the debugging was working and the environment was properly setup it was time to test some simple tasks on the platform The aim for the simple tasks was to test features that could be used later on in the project Some of the tested functions were control the LEDs try the scheduling and task priorities semaphores print text on serial ports and also some interrupts 7 2 Start to talk to the NFC breakout board When the project mastered the environment and the platform it could connect the NFC breakout board to the Midrange platform The NFC board was as described in section 5 3 on page 22 connected to the TTL level of one of the UART ports In the beginning the focus was to understand the messages that was replied by the breakout board To be able to initialize the NFC module and the embedded microprocessor a special wakeu
45. ork type peer to peer Point to Point to peer to peer multipoint multipoint Range up to 0 1 m 30m 50m up to 1 m Speed 424 Kbit s 2 1 Mbit s 200 Kbit s up to 16 Mbit s Set up time lt 0 1s lt 6s lt 3 ms 0 5 s Security yes hardware yes software yes software no except and secure card IRFM IC Communicatio active active active active active active active active mode active passive Costs Low moderate low moderate low low Frequency 13 56 MHz 2 4 2 5 GHz 2 4 2 5 GHz not applicable Power con gt 15 mA lt 30 mA lt 15mA not available sumption The most widespread competitor is bluetooth 2 1 but it does have some security issues Bluetooth low energy BLE is the newest of the one in table 3 1 and maybe also the biggest competitor BLE has not as good numbers as NFC but it is the 10 3 3 NFC COMPETITORS closest and best competitor to NFC All of these competitors are functional over a longer distance compared to NFC This seems to be an advantage but in some applications it might be a problem NFC is intended to work over a very short range due to its often security critical applications The longer the range of the communication is the more threats are directed towards it This the low power consumption and the extremely short set up time might be the biggest advantages of NFC 11 12 PO NFC modules NXP is the world leading manufacturer of NFC devices in fact they currently almost have
46. ortant when designing the enclosure of the antenna The range of the antenna is from the beginning very short therefore it is more interesting to see what is happening when a shield also becomes in between than to measure the distance Different kinds of shields were tested for the antenna both on the NFC breakout board and the desktop reader The tested shields were a thick plastic shield 1 cm thick a metal plate 2 mm and a piece of cardboard wrapped in aluminium foil all shields are depicted in figure 7 7 on page 42 These three kinds of shields are considered as possible to be used in the chassis that will be used later if the reader can read the tag The plastic shield will probably act more as a obstacle than a shield The metal and aluminium shields are not grounded and are big compared to the magnetic field which means that it will not have any gaps In theory the antenna s range is decided by several parameters One of these parameters are dependent of the medium between the reader and the tag skin depth shows how much a signal can penetrate different medium In the skin depth equation 7 1 jz is the magnetic permeability is the electrical conductivity and f is the operating frequency The equation just gives a hint about range of 39 CHAPTER 7 THE IMPLEMENTATION PHASE the antenna a full set of parameters of must be considered when designing an enclosure 7 1 40 7 7 MEASURING ANTENNA PERFORMANC
47. p command must be sent see section 6 1 3 on page 30 This wakeup command contains different settings for the microprocessor and some NFC specific functions A flowchart of the beginning of the main file can be examined in figure 7 1 on the facing page 7 2 1 Debugging with NFC Debugging with the NFC functions was discovered to be hard The normal debugging via the JTAG was not possible since the microprocessor in the NFC module timeouts if it not receives the next byte within a short period of time For debugging NFC an on beforehand undiscovered method could be used the COM port belonging to the TTL level UART connected to the breakout board By connecting the COM port to a computer and a terminal application the commands sent from the Midrange to the NFC board could be debugged The setup is illustrated in figure 7 2 on page 34 The bytes sent the other way could however not be debugged 32 7 3 READING PASSIVE TAGS WITH THE MIDRANGE PLATFORM Include needed files Definitions Create and schedule tasks NFC_control_Task LED_control_Task Initialise PN532 NFC_init_rdy false false true Status LED blink Status LED blink fast slow Initialise again NFC_init_rdy true Check firmware Continues on another figure Figure 7 1 The beginning of the main file 7 3 Reading passive tags with the Midrange plat form In the NFC kit see section 5 4 on
48. r is 36 NFC NFC NFC NFC NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 40 NFC NFC NFC NFC NFC NFC NFC NFC NFC NFC Add 4 Bytes to response data for next iteration Number of bytes received from initiator is 3 end gt Last Data packet end from initiator detected Prepare end to be send back as response too Figure A 2 The output from NXP s software acting as target 59 OANDOTBWNH 67 68 APPENDIX A OUTPUTS FROM BOTH NXP S SOFTWARE AND FROM THE PROJECT S SOFTWARE Poll Result hLogHandle 1 Session Opened 1 xxx 424 Active x x xxx NFC Protocol x xx NFCID3t AA 99 88 77 66 55 44 33 22 11 DIDt 00 NADt 01 TgGeneralBytesLength 0x08 TgGeneralBytes hex 4D 69 64 72 61 6E 67 65 TgGeneralBytes char M i d r a n g e Connecting to remote device gt Connect Successful OK a priori SendLength 6 Index 0 ReceiveLength 4000 Receivelndex a posteriori SendLength 6 Index O ReceiveLength 18 Receivelndex Iteration 5 Transceive done Total Response Data Received from Target 18 NFC from Syntronic Add 1 bytes to SendBuffer for next iteration a priori SendLength 7 Index 0 ReceiveLength 4000 Receivelndex a posteriori SendLength 7 Index O ReceiveLength 18 Receivelndex Iteration 4 Transceive done Total Response Data Received from Target 18 NFC from Syntronic Add 1 bytes to Se
49. rm is called Midrange and is used in many projects delivered by Syntronic The Midrange hosts a Cortex M3 6 processor and many connections to peripherals The implementation should firstly focus on to determine if NFC is a good solution in a charging pole for 1 CHAPTER 1 BACKGROUND electrical cars and secondly on writing generic and useful code After this project Syntronic will evaluate NFC with this thesis as a decision base The implementation should therefore be prepared for other projects by making the code as generic as possible 1 1 1 Requirements on the hardware and the software within this project In this project NFC should be implemented on a multi purpose platform The platform holds several functional blocks that can be adapted to the customer and the application Syntronic wants a new functional block with NFC The block should be similar to an application programming interface APD 7 The project will also investigate different NFC modules and other hardware a complete list of the tasks for the project can be found in the list below e Make a substantial study about NFC in general to be able to solve the project s problems e Investigate different NFC vendors and modules e Choose the hardware best suited for this project e Investigate different needs for diverse applications e Determine if NFC is worth to implement in a charging pole e Implement a generic software that can act as a solid start in many
50. s processors cortex m cortex m3 php ARM Holdings plc 2011 01 19 1 7 Application programming interface wikipedia the free encyclopedia http en wikipedia org wiki Application programming interface Wikime dia Foundation Inc 2011 07 27 2 51 BIBLIOGRAPHY 8 9 10 11 12 13 14 15 16 17 18 19 20 52 Identification friend or foe iff systems Iff questions answers http www dean boys com extras iff iffqa html Dean Boys 2011 07 27 3 4 RFID Centre RFID http www rfidc com docs introductiontorfid _ technology htm RFID Centre Ltd 2011 01 27 4 D M Dobkin The RF in RFID Amsterdam Newnes 4 S Gittlen The failure of rfid computerworld http www computerworld com s article 9001194 The_failure_of RFID Computerworld Inc 2011 07 28 4 A A R M M Tentzeris L Yang and T Wu Rfid s on paper using inkjet printing technology Is it the first step for uhf ubiquitous cognitive intelligence and global tracking 4 Smart card overview http www smartcardbasics com smart card overview html CardLogix Corporation 2011 07 27 5 Smart card types http www smartcardbasics com smart card types html CardLogix Corporation 2011 07 27 5 A Parkinson Will 2011 be the year nfc finaly takes off gfk techtalk http www gfktechtalk com 2010 11 22 will 2011 be the year nfc finally t
51. software starts with a similar choice as in the code written in this project the user s choice of active communication as a initiator or a target The output from the software communicating with the Midrange as a target and as an initiator can be seen in Appendix A on page 57 44 8 2 ANTENNA PERFORMANCE 8 2 Antenna performance There was some additional time left in the time budget at the end since the hardware comparison part and some parts of the implementation part became smaller than what was planned from the beginning The additional time was used to measure the performance of the antenna The antenna on the breakout board has empirical showed that it is better than the one in the desktop reader For Syntronic it would be interesting to see how good the antenna performs especially since it should probably be embedded in a chassis in future projects Without any shield or obstacles the antennas performed different the antenna on the breakout board could read a tag from maximum 6 2 cm and the desktop reader from maximum 2 4 cm When communicating with each other the antennas must be within 2 3 cm 8 2 1 Thin metal plate The thin metal plate has an unknown compound of some kind of plate Plate is similar to steel which is the metal closest to plate that have its characteristics in regular tables and therefore the chosen values for the magnetic permeability and the electric conductivity are for steel 1 Fues 2013 8
52. st parts involved in a complete NFC system ISO 18092 defines NFCIP 1 which deeply describes the interface and protocol used in an 18092 certified NFC system NFCIP 1 carries the definition of the different modes active passive RF protocol interface general protocol flow RF collision avoidance transport and data exchange protocol All parts of NFCIP 1 is important when designing a NFC device if it does not follow NFCIP 1 it might not be compatible with other devices 3 2 3 ISO 21481 The standard ISO 18092 was the first pure NFC standard and NFCIP 1 in that standard defined the interface and protocol used in an NFC system The continuing of NFCIP 1 is called NFCIP 2 20 and it is defined in ISO 21481 NFCIP 2 9 CHAPTER 3 NFC IN GENERAL contains much less definitions compared to NFCIP 1 NFCIP 2 has information about external RF field threshold and detection mode selection and RF detection and initial RF generation Like NFCIP 1 these are important when designing devices that should be compatible with the ISO 21481 standard 3 3 NFC competitors NFC has some similar technologies to compete with These has become more interesting since the problems described in section 3 1 on page 7 Some scientists has grown tired about NFC that it not can get its real breakthrough Therefore some competitors has arisen these can be compared in table 3 1 21 Table 3 1 Comparison of NFC s competitors Netw
53. t knowledge about NFC and therefore get enough information to modify and write new functions for the contemplated application The need of simple code and already ready routines are important for an another project s member that just want to use NFC in their implementation how it works is not important in just that case The code was written to make things easier for the user of the code A function that e g sends data takes care of establishment of the communication link and to 38 7 7 MEASURING ANTENNA PERFORMANCE send data no matter which device that are initiator or target If the user wants to change something he must go one level deeper this level is however not that much harder than the highest but he will need more understanding about NFC 7 7 Measuring antenna performance The NFC board or a similar version will probably be used in at least one project delivered by Syntronic The antenna will most likely be embedded in some kind of case in upcoming projects The performance of the antenna will therefore be important The antenna type on both the breakout board and the desktop reader is a coil antenna printed on the PCB They have the exact same shape but the size of them is different The area of the antenna on the breakout board is more than eight times the antenna on the desktop reader Testing if the antenna is powerful enough to read a passive tag through a shield carried out the antenna test The test could be imp
54. tion is different from the passive communication first the link must be established then data can be exchanged The two devices exchanging their ID establish the link each device can only be connected to one link The link and the communication have two roles initiator and target these are similar to the usual master and slave roles but are more equal It is the initiator that initiates the link establishment When the link is established the two devices are becoming even more equal both devices can start to send data and receive data The NFC message passing is intelligent designed the design has made it unnecessary to have any send or receive buffer The design of the message passing is similar to the one in figure 6 1 on page 27 Both devices alter sending and receiving the initiator sends data and waits for an answer that optionally can contain data from the target If the target has no data to reply with it just add 0x01 to the command code sent by the initiator The chain of messages following the structure in figure 6 1 on page 27 is equivalent for both passive and active communication but normally the chain is longer for the active version The program written to test this implementation is depicted in figure 7 4 on the facing page and starts with the flowchart in figure 7 1 on page 33 If the active mode and then the target mode is chosen the program will follow the structure in figure 7 5 on page 38 For the initiator mode the respectively
55. tive coupling With an inductive coupled system the tag operates within the induced magnetic field from the reader Often the induced field provides the tag with all the needed power to the tag This makes it possible to construct very simple tags as mentioned before these could even be printed on paper or plastic The RFID tags can also have different power methods passive semi passive and active The passive version powers up and backscatter a signal using the power emitted from the reader Semi 4 2 3 SMART CARD passive uses a battery to power the circuits on the tag but uses the emitted energy from the reader to backscatter the signal An active tag has power on board both to the circuits and to transmit the radio signal that is sent back to the reader Of course the different power modes have different usages and prices The passive version is the cheapest and often the most short ranged RFID has been successful in a lot of implementation and it is still an active topic in research despite its age of around half a century RFID is today most common in animal tracking transport tracking car tolls and access systems 2 3 Smart card Smart cards are common today since the card issuers have started to replace the magnetic stripes on credit cards with a smart card implementation A smart card has a small microprocessor embedded on the card and open contact areas 13 The microprocessor is activated when the card is inserted in
56. with a lower bandwith The applications for ISO 15693 is much fewer than for NFC As mentioned in section 3 2 1 on page 9 many NFC devices can emulate existing cards The cards that can be emulated are common in public transportation payment and identification systems The cards used in such systems are often of different types and not all modules support all of them the supported systems for each module can be found in table 4 1 on the facing page The modules also support various baudrate when communicating over NFC the baudrates ranges from 106 kbit s to 848 kbit s The security functions is often demanded by some applications Therefore some additional security functions are supported by most of the NFC modules MIFARE classic is a MIFARE with a memory and additional security functions it is developed by Philips NXP The smart card controller is often the one controlling the secure 14 4 1 COMPARISON OF NXP S MODULES element and there are mainly two interfaces for the communication S C or SWP The modules with a CPU on board have a firmware that can be updated to support more functions or restored when the device is not functional correct The last part of table 4 1 compares the power consumption and its functions and also the physical characteristics of each module The power consumption part is very important when choosing the right module This is because the module often should be embedded in a mobile device with str
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