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

3.4.4 Update Binary

The Update Binary command can only be issued when a file has been selected by an NFC device. If a file has not been selected when an Update Binary is issued, then the error code 0x6982 is sent back to the NFC device. In order for a file to be modified by the Update Binary command the write privileges of the file need to be checked. If the NFC device does not have the privileges to write the file, the error code 0x6A86 is returned.

The Update Binary contains the Lc byte, which is equal to the length of the Data Bytes being sent. The Data Byte fields contain the data to be written into the tag. The Update Binary command shall not have the Le byte.

If the NFC device has the proper write privileges, the Lc byte is then checked with the maximum file size of the selected file. If the length exceeds the maximum file size, then the error code 0x6A86 is returned. Otherwise, the data within the file is overwritten with the Data Field bytes sent by the NFC device.

A special case of the Update Binary commands occurs when an NFC device attempts to overwrite the CC file. The only byte that is allowed to be updated in the CC file is the write privileges of the file. To update the write privilege, the Lc byte should be set to 0x01 and the only Data Field byte should be the new write privilege for the CC file.