SLOA208B November   2014  – March 2019 TRF7970A , TRF7970A

 

  1.   NFC card emulation using the TRF7970A
    1.     Trademarks
    2.     Terms, Definitions, and Symbols
    3. 1  Introduction
    4. 2  Card Emulation
      1. 2.1 Anticollision
        1. 2.1.1 Card Emulation Type A
        2. 2.1.2 Card Emulation Type B
      2. 2.2 Data Exchange
    5. 3  Configuration and Commands for Type 4 Tag Platforms
      1. 3.1 Overview of Type 4 Tag Configuration
        1. 3.1.1 Tag
        2. 3.1.2 Applications
        3. 3.1.3 Files
      2. 3.2 Firmware Structure
        1.       Example 1. Type 4 Tag Structures Within Example Firmware
        2. 3.2.1 tType4AppDS
        3. 3.2.2 tType4App
        4. 3.2.3 tType4File
        5. 3.2.4 Example Setup
          1.        Example 2. Example Setup of a Type 4 Tag Structure
      3. 3.3 File Structure
        1. 3.3.1 Capability Container
          1.        Example 3. Format of the Capability Container for a Tag With Two Files
        2. 3.3.2 Text RTD
          1.        Example 4. Example of a Text RTD Within an NDEF File
        3. 3.3.3 URI RTD
          1.        Example 5. Example of a URI RTD Within a Proprietary File
        4. 3.3.4 Smart Poster
        5. 3.3.5 V-Card
        6. 3.3.6 MIME
      4. 3.4 Available Type 4 Tag Commands
        1. 3.4.1 Frame Format
        2. 3.4.2 Select
        3. 3.4.3 Read Binary
        4. 3.4.4 Update Binary
      5. 3.5 Modifying Stored Tag Information
    6. 4  Hardware Description
      1. 4.1 LaunchPad™ Development Kit and BoosterPack™ Plug-in Module Setup
        1. 4.1.1 BoosterPack Plug-in Module: DLP-7970ABP
        2. 4.1.2 LaunchPad Development Kit: MSP-EXP430F5529LP
        3. 4.1.3 LaunchPad Development Kit: MSP-EXP432P401R
      2. 4.2 Bundle Available for Purchase
    7. 5  Card Emulation Firmware Example
      1. 5.1 Card Emulation APIs
      2. 5.2 Implementing a Card Emulation Sample Application
        1. 5.2.1 Low-Level Initialization
          1.        Example 6. MCU and TRF7970A Initialization Code Snippet
        2. 5.2.2 Card Emulation NFC Stack Setup
          1.        Example 7. Card Emulation Initialization Code
        3. 5.2.3 Emulation of Different RTDs
    8. 6  Quick Start Guide
    9. 7  Operational Overview
    10. 8  Card Emulation Interoperability Results
    11. 9  Conclusion
    12. 10 References
  2.   Revision History

2.1.1 Card Emulation Type A

The frame format for Data Exchange Protocol (DEP) packets at 106 kbps during anticollision(see Figure 3) is based on NFC-A technology specifications in NFCForum-TS-DigitalProtocol-1.0 or the ISO 14443-3 specifications.

fig03_frame_format_type_a.gifFigure 3. Frame Format for Card Emulation Type A Commands During Anticollision

Initially, when configured for Type 4A tag platform emulation, the TRF7970A must be receiving without CRC, because of the ISO 14443A protocol being used. After receiving commands from the reader/writer, the following registers must be modified before and after the anticollision is completed:

  1. ISO Control Register (0x01) → 0xA4 (ISO 14443A 106 kbps, receive without CRC during anticollision, before Select command)

    2. or

  2. ISO Control Register (0x01) → 0x24 (ISO 14443A 106 kbps, receive with CRC, after anticollision is completed).
  3. Send packet:
    1. Reset FIFO (0x0F) direct command.
    2. Transmission without (0x10, anticollision before Select command) or with (0x11, after anticollision is completed) CRC direct command.
    3. TX Length Byte 1 and 2 (0x1D and 0x1E) registers
    4. Write the response to the FIFO.

The ISO control register needs to be modified for the anticollision state to receive without CRC for the required commands (See the TRF7970A data sheet and ISO/IEC 14443-3 specification for more information). When the anticollision is completed, the ISO Control register needs to be modified to receive with CRC. Step 2 must be used to send commands to the reader/writer.

Figure 4 shows the Type A anticollision flowchart. The TRF7970A supports only 106 kbps for card emulation of Type A.

fig04_type_a_anticoll.gifFigure 4. Card Emulation Type A Anticollision