• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 17 subscribers
  • Views 595 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TRF7970A in card emulation mode

Nitin Gote
Prodigy 185 points
Other Parts Discussed in Thread: MSP430F4616, TRF7970A

Hello Sir,

I'm working on the TRF7970A in card emulation mode with Samsung google Nexus 4 mobile. I interfaced the TRF7970A with MSP430f4616 in parallel mode. Initially i faced the problem like when the reader and tags come nearby at that time card should detect the RF field generated by reader and generate an interrupt to the MCU, and this was not happening,it seems that card was not able to detect the RF field and generate an interrupt. Now i solved this problem.Now i'm checking the register 0x19 to make sure that reader is still on the protocol type B as i set up for. But it's not working that means there is problem in Type B command as it is not 0xC5.

It can be the issue that TRF7970A registers are not programmed correctly for card emulation mode.So I checked the settings of all the registers of TRF7970A and it is fine as.So please help me in finding what could be the issue with the code.I have attached the code here 6567.card_emulation.zip

  • 0
    TI__Guru* 91086 points

    Nitin - 

    As you may know the handset is polling through the technologies and modes and so then i must point out to you that Register 0x19 is for indicating what is the protocol/bit rate of the first command being sent over the air to the TRF7970A, not the other way 'round. 

    For example, 0xC9 = ISO14443A @ 106kbps, 0xC5 = ISO14443B @ 106kbps, 0xD3 = FeliCa @ 424, etc. 

    The register 0x01 is the main register used to setup the TRF7970A for the mode... 

    For example, to do CE mode, a 0x24 = ISO14443A @ 106kbps, 0x25 = ISO14443B @ 106kbps.

    Logic Shots of what you are doing would be more helpful to us, as we may or may not have the time to analyze your code.

    Here are some to get you going. (free viewer from www.saleae.com/downloads)

    2620.TypeB_CE.7z 

     

  • 0 in reply to Josh Wyatt
    Prodigy 185 points

    Thank you sir for your response.

    I already know what you mentioned in the reply, i completely agree with it and i have done the things in the same way. As i checked each and every bit of registers, all register values are right. But the condition for NFC target protcol register (0x19) to make sure that reader is still on protocol types (i.e. an ISO14443B command at 106 kbps was  not issued), always fails. It is supposed to be read as 0xC5 as the card is in ISO14443B @106kbps mode; but instead it reads as 0x00 all the time.

    I have seen your previous post on same card emulation subject with same problem, which helped me to clarify some of the doubts, but please tell me how to overcome this problem. 

    I will try to post the logic analyzer shots as soon as possible.

    Thank you.     

  • 0
    Prodigy 55 points

    Hi All,

    I am facing the same problem that TRF7970A is unable to detect RF field when I try to read using my Nexus 4. I am using TRF7970A EVM Rev A and the TI TRF7970A Booster Pack CE example code provided by Josh Wyatt in the following post http://e2e.ti.com/support/wireless_connectivity/f/667/t/270972.aspx?pi310978=1

    I attach the code here as well 1777.6507.Card Emulation TRF7970EVM Parallel Mode Jan 7.zip

    Please let me know how you managed to solve the issue. Thanks.

    Regards

    Hammad