nfc-pn544.rst 1.3 KB

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  1. ============================================================================
  2. Kernel driver for the NXP Semiconductors PN544 Near Field Communication chip
  3. ============================================================================
  4. General
  5. -------
  6. The PN544 is an integrated transmission module for contactless
  7. communication. The driver goes under drives/nfc/ and is compiled as a
  8. module named "pn544".
  9. Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C.
  10. Protocols
  11. ---------
  12. In the normal (HCI) mode and in the firmware update mode read and
  13. write functions behave a bit differently because the message formats
  14. or the protocols are different.
  15. In the normal (HCI) mode the protocol used is derived from the ETSI
  16. HCI specification. The firmware is updated using a specific protocol,
  17. which is different from HCI.
  18. HCI messages consist of an eight bit header and the message body. The
  19. header contains the message length. Maximum size for an HCI message is
  20. 33. In HCI mode sent messages are tested for a correct
  21. checksum. Firmware update messages have the length in the second (MSB)
  22. and third (LSB) bytes of the message. The maximum FW message length is
  23. 1024 bytes.
  24. For the ETSI HCI specification see
  25. http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx