SLOA227B October   2015  – March 2019 TRF7964A , TRF7964A , TRF7970A , TRF7970A

 

  1.   NFC/HF RFID reader/writer using the TRF7970A
    1.     Trademarks
    2. 1  Terms, Definitions, and Symbols
    3. 2  Introduction
    4. 3  Initial RF Collision
    5. 4  TRF7970A Register Settings
    6. 5  Reader/Writer Mode
      1. 5.1 Technology Activation Using the TRF7970A
        1. 5.1.1 ISO14443-3 Type A (Type 2 and Type 4A Tags)
          1. 5.1.1.1 Additional Tag Activation Commands for Type 4A Tags
        2. 5.1.2 ISO14443B-3 (Type 4B Tags)
          1. 5.1.2.1 Selection for Type 4B Tags
        3. 5.1.3 ISO18092 (Type 3 Tags)
        4. 5.1.4 ISO15693 (Type 5 Tags)
      2. 5.2 Tag Memory Format With NDEF Examples
        1. 5.2.1 Type 2 Tags
          1. 5.2.1.1 Layout
          2. 5.2.1.2 NDEF Format
            1. 5.2.1.2.1 Static Memory Structure
            2. 5.2.1.2.2 Dynamic Memory Structure
          3. 5.2.1.3 Capability Container
        2. 5.2.2 Type 3 Tags
          1. 5.2.2.1 Layout
          2. 5.2.2.2 NDEF Format
          3. 5.2.2.3 Attribute Information Block
        3. 5.2.3 Type 4 Tags
          1. 5.2.3.1 Layout
          2. 5.2.3.2 NDEF Format
          3. 5.2.3.3 Capability Container
        4. 5.2.4 Type 5 Tags
          1. 5.2.4.1 Layout
          2. 5.2.4.2 NDEF Format
          3. 5.2.4.3 Capability Container
    7. 6  Hardware Description
      1. 6.1 LaunchPad™ Development Kit and BoosterPack™ Plug-in Module Setup
        1. 6.1.1 BoosterPack Plug-in Module: DLP-7970ABP
        2. 6.1.2 LaunchPad Development Kit: MSP-EXP430F5529LP
        3. 6.1.3 LaunchPad Development Kit: MSP-EXP432P401R
      2. 6.2 Bundle Available for Purchase
    8. 7  Reader/Writer Firmware Example
      1. 7.1 Reader/Writer APIs
      2. 7.2 Implementing a Reader/Writer Sample Application
        1. 7.2.1 Low-Level Initialization
          1.        Example 1. MCU and TRF7970A Initialization Code Snippet
        2. 7.2.2 Reader/Writer NFC Stack Configuration
          1.        Example 2. Reader/Writer Stack Configuration Code Snippet
        3. 7.2.3 Activation
        4. 7.2.4 Reading and Writing Tags
    9. 8  Quick Start Guide
    10. 9  Operational Overview
    11. 10 Reader/Writer Interoperability Results
    12. 11 Conclusion
    13. 12 References
  2.   Revision History

5.2 Tag Memory Format With NDEF Examples

The NFC Data Exchange Format (NDEF) specification is a data format standard for storing information on NFC tag platforms in messages. The composition of NDEF messages are determined by the various NFC Forum Record Type Definition (RTD) formats. Among the supported RTD formats are Text, Uniform Resource Identifier (URI), Smart Poster, V-Card, and MIME. The examples for the following sections focus on the NFC Forum Text RTD structure.

The method to detect and read/write NDEF contents vary between tag types, but one common factor is the requirement for basic information needed to read the contents of an NDEF formatted message. In most tags, this is called the Capability Container (CC) file. The exception to that is with Type 3 tags, which instead have an 'Attribute Information Block'. The information stored in these bytes is used to determine the mapping specification, data sizes, read and write access, and other parameters. According to the current specifications of each tag type, only after the CC (or Attribute Block) is read can the NDEF contents of a tag be read.

For most tag types, with Type 3 being the exception once again, information about NDEF messages are stored with Tag, Length, Value (TLV) bytes. The Tag field provides information on the format and the Length field indicates the length of the NDEF message. For Type 2 and Type 5 tags, the Value field is where the NDEF message itself is stored. For Type 4 tags, the Value field contains additional information about the NDEF message. Based on each NFC Forum tag specification, the TLV bytes may not be separate and must follow one another sequentially.

The following sections describe the basics of the memory layout, NDEF formatting, and Capability Container (or Attribute Block) for each tag type. For further details, review the NFC Forum specifications for each tag type. References for each specification can be found in Section 12.