This unstable has cause the Pass Through in NXP to OFF. I finally realise that the failure of Peer NFC device write through RF interface is caused by the unstable RF field itself provided. How is your trip ? Is it a foreign country business trip ?įor the wait time, I do not change anything. You can still write to session registers from the I2C side. This means that write access will be locked from the corresponding interface (I2C and/or RF). As mentioned in the datasheet, setting bits REG_LOCK_I2C or REG_LOCK_RF to 1 is permanent and cannot be reset.

May I know what does this means ? If I accidentally set to 1b, then how can I reset it back to 0b ? Or the chip is consider scrapped ? Lastly, may I know how can I modify the Register Lock bytes ? It says that ' Once set to 1b, cannot to reset to 0b anymore'. For configuration registers you can use the same WRITE command as for SRAM, using addreses 0圎8-0圎9. Session registers cannot be written from RF side, only read is allowed.

Is it the same method as writing the mapped SRAM ? in which we just need to write to the memory address. 0xF8, 0xF9, 0圎8, and 0圎9. Just notice that session registers are in Sector 3 (addresses 0xF8-0xF9), so you need to use the SECTOR SELECT command first.įor write NXP NTAG Register (configuration and session) from RF interface: Yes, you can use the same READ command as for SRAM. Is it the same method as reading the mapped SRAM ? in which we just need to read from the memory address. 0xF8, 0xF9, 0圎8, and 0圎9. Second packet send to NXP NTAG I2C 1K RF interface : 0x00, 0x00, 0x00, 0x00, CRC, then NO REPLY from NXP NTAG I2C 1K RF interface.įor read NXP NTAG Register (configuration and session) from RF interface: I have follow this procedure of writing to NXP NTAG I2C 1K RF interface, which is the following sequence:įirst packet send to NXP NTAG I2C 1K RF interface : 0xC2, 0xFF, CRC, then wait for ACK from NXP NTAG I2C 1K RF interface. There should have ACK send back but no reply from NXP NTAG I2C 1K RF interface. Failure occurred after send out first packet to NXP NTAG I2C 1K RF interface. Device A has return a timeout message to its host, which also meant that timeout while waiting for packet from NXP NTAG I2C 1K. However, instead of read it back after NXP NTAG I2C 1K is written (64 bytes) by its host, I write 64 bytes to the Mapped SRAM (0xF0) using device A. I have successfully write to SRAM of NXP NTAG I2C 1K and then read back using device A from NXP NTAG I2C 1K RF interface mapped SRAM address 0xF0. I am reading and then writing to NXP NTAG I2C 1K using another NFC device - Device A.ĭuring reading and writing, Pass Through is constantly ON and then RF wave is constantly emitted to NXP NTAG I2C 1K.

Nfc write sector 0 command