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

5.1.2.1 Selection for Type 4B Tags

After activation is finished for a Type 4B tag the ATTRIB command must be issued to finish the selection of the tag to exchange data with it. The ATTRIB command sends the tag information on timing requirements, framing specifications for RF communication and for data packets, supported communication bit rates, and the CID value assigned to the tag.

To determine the highest mutually supported bit rate between the tag and the reader/writer the tenth byte of the SENSB_RES is compared with the enabled reader/writer bit-rate setting. One of the bytes in the ATTRIB command is then set to tell the tag to operate at that bit rate. The possible bit rates are: 106 kbps, 212 kbps, 424 kbps, and 848 kbps.

The response to the ATTRIB (Answer to ATTRIB) is an acknowledgment that it received the ATTRIB command. Upon receiving the ATTRIB response, the firmware sets the ISO Control Register (0x01) with the correct settings to transmit data at the previously determined bit rate. Now the reader/writer and Type 4B tag can enter data exchange. For further detail on the format of the ATTRIB command, refer to the ISO14443-3 specification.