NFC ZigBee 3.0 Modules and Libraries: ntag_nwk.h File Reference

NTAG Network NDEF reading and writing (interface)

ntag_nwk.h contains high level APIs for reading and writing a network NDEF to the NTAG suitable for use in commissioning devices into an IEEE 802.15.4 network.

The typical set up sequence is the same for the data APIs (described in ntag.h).

A typical sequence to read data is shown below. It is recommended that data is read when the NTAG is removed from a field (as the data in the NTAG may have been altered whilst in the field) in response to the E_NTAG_EVENT_ABSENT event.

• NTAG_vTick() is called by the application
• APP_NtagCbEvent(E_NTAG_EVENT_ABSENT) is called in the application
• NTAG_NWK_eRead() is called by the application, handing control of the low-level data APIs over to the NDEF data module. A pointer to be filled in with the address of the read and a pointer to store the NDEF payload is provided. This function call will return E_NTAG_NWK_READING if the request is successful.
• NTAG_NWK_eTick() should then be called regularly by the application (replacing the calls to NTAG_vTick()).
• If NTAG_NWK_eTick() returns E_NTAG_NWK_READ_OK the read was successful. The NDEF payload and the address of the read will have been placed into the pointers provided in the NTAG_NWK_eRead() call.
• If NTAG_NWK_eTick() returns E_NTAG_NWK_READ_FAIL the read was unsuccessful.
• If the interaction with the NDEF data is finished NTAG_NWK_eStop() should be called followed by a call to NTAG_vRegCbEvent() to reclaim the NTAG event callback, followed by regular calls to NTAG_vTick().

A typical sequence to write the NDEF payload data is shown below. It is recommended that data is written when the NTAG is not in a field (as a reader may be writing whilst in the field). Data may also be written following a successful read as shown below:

• NTAG_NWK_eTick() returns E_NTAG_NWK_READ_OK indicating a successful read.
• The NDEF payload contents are updated for writing.
• NTAG_NWK_eWrite() is called by the application, handing control of the low-level data APIs over to the NDEF data module. A pointer with the address of the write and a pointer to NDEF payload data to be written is provided. This function call will return E_NTAG_NWK_WRITING if the request is successful.
• NTAG_NWK_eTick() should then be called regularly by the application (continuing to replace the calls to NTAG_vTick()).
• If NTAG_NWK_eTick() returns E_NTAG_NWK_WRITE_OK the write was successful.
• If NTAG_NWK_eTick() returns E_NTAG_NWK_WRITE_FAIL the write was unsuccessful.
• If the interaction with the NDEF data is finished NTAG_NWK_eStop() should be called followed by a call to NTAG_vRegCbEvent() to reclaim the NTAG event callback, followed by regular calls to NTAG_vTick().

The message sequence chart below shows a sequence of function calls for initialisation, an NDEF read and an NDEF write: