SLOA192B April 2014 – March 2019 TRF7970A , TRF7970A
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NFC active and passive peer-to-peer communication using the TRF7970A
- Trademarks
- 1 Introduction
- 2 Initial RF Collision
- 3 TRF7970A Register Settings
- 4 Peer-to-Peer at 106 kbps
- 5 Peer-to-Peer at 212 kbps and 424 kbps
- 6 Hardware Description
- 7 Passive and Active Peer-to-Peer Firmware Example
- 8 Quick Start Guide
- 9 Operational Overview
- 10 Peer-to-Peer Interoperability Results
- 11 Conclusion
- 12 References
- Revision History
5.1.2 Target
After receiving commands from the initiator, the transceiver must follow the next steps each time before responding to the initiator:
- Delay time specified in the technology specification (56 µs to 188 µs).
- Perform Response RF Collision avoidance, and ensure no RF field is detected.
- ISO Control register (0x01) → 0x32 (NFC-F at 212 kbps).
- Delay 1 ms
- Send packet:
- Reset FIFO (0x0F) direct command.
- Transmission with CRC direct command (0x11).
- TX Length Byte 1 and 2 (0x1D and 0x1E) registers.
- Write the response to the FIFO.
NOTE
For more details on the NFC-F protocol, see [2], [3], [6], [7] and [8].
Figure 12. Peer-to-Peer 212-kbps Active Initiator Anticollision