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

4 TRF7970A Register Settings

After powering up the TRF7970A, sending SOFT_INIT (0x03) and IDLE (0x00) direct commands enables the passive target mode at 106 kbps. Table 2 lists the default value of registers 0x00 to 0x16 and 0x18h to 0x1C after the commands are issued. Furthermore, it shows the registers that must be modified from their default values for reader/writer mode.

The ISO Control (0x01) register is modified whenever the reader/writer technology or bit rate changes. The Chip Status Control (0x00) register is modified after initialization, and whenever the RF field is enabled or disabled. The Special Function (0x10) register requires modification for writing to Type 2 tags. The Modulator and SYS_CLK Control (0x09), RX Special Settings (0x0A), and Regulator and I/O Control (0x0B) registers need to be modified only once, after initialization. The NFC Target Detection Level register must be modified after initialization based on the TRF7970A silicon errata.

Table 2. TRF7970A Default Register Values After SOFT_INIT and IDLE Direct Commands

Address Register Value Requires Modification
0x00 Chip Status Control 0x01 Yes
0x01 ISO Control 0x21 Yes
0x02 ISO14443B TX options 0x00 No
0x03 ISO14443A high bit rate options 0x00 No
0x04 TX timer setting, H-byte 0xC1 No
0x05 TX timer setting, L-byte 0xC1 No
0x06 TX pulse-length control 0x00 No
0x07 RX no response wait 0x0E No
0x08 RX wait time 0x07 No
0x09 Modulator and SYS_CLK control 0x91 Yes
0x0A RX Special Setting 0x10 Yes
0x0B Regulator and I/O control 0x87 Yes
0x0C IRQ status 0x00 No
0x0D Collision position and interrupt mask 0x3E No
0x0E Collision position 0x00 No
0x0F RSSI levels and oscillator status 0x40 No
0x10 Special Function 0x00 Yes
0x11 Special Function 0x00 No
0x12 RAM 0x00 No
0x13 RAM 0x00 No
0x14 Adjustable FIFO IRQ Levels 0x00 Optional
0x15 Reserved 0x00 No
0x16 NFC Low Field Detection Level 0x00 No
0x18 NFC Target Detection Level 0x00 Yes
0x19 NFC Target Protocol 0x00 No
0x1A Test 0x00 No
0x1B Test 0x00 No
0x1C FIFO status 0x00 No