nfc-pn544.rst (1294B)
1============================================================================ 2Kernel driver for the NXP Semiconductors PN544 Near Field Communication chip 3============================================================================ 4 5 6General 7------- 8 9The PN544 is an integrated transmission module for contactless 10communication. The driver goes under drives/nfc/ and is compiled as a 11module named "pn544". 12 13Host Interfaces: I2C, SPI and HSU, this driver supports currently only I2C. 14 15Protocols 16--------- 17 18In the normal (HCI) mode and in the firmware update mode read and 19write functions behave a bit differently because the message formats 20or the protocols are different. 21 22In the normal (HCI) mode the protocol used is derived from the ETSI 23HCI specification. The firmware is updated using a specific protocol, 24which is different from HCI. 25 26HCI messages consist of an eight bit header and the message body. The 27header contains the message length. Maximum size for an HCI message is 2833. In HCI mode sent messages are tested for a correct 29checksum. Firmware update messages have the length in the second (MSB) 30and third (LSB) bytes of the message. The maximum FW message length is 311024 bytes. 32 33For the ETSI HCI specification see 34http://www.etsi.org/WebSite/Technologies/ProtocolSpecification.aspx