NTAG 5 NFC Read Write Issue

[Vishu203]

Hi, I am using the NTAG 5 plus chip NTP53321G0JTZ together with an antenna I designed myself to establish NFC communication between the tag and my phone and my device through I2C. At first, I can both write to it and read from it with the help from your applications TagInfo and TagWriter. However when I established the communcation of my tag with device and write data through I2C write, I am not able to write to the tag anymore, when I am using the TagInfo application and scan the tag it is said to be NdefFormatable and not NDef Format Enabled and on the IC info side I do not get the “NFC Forum NDEF-compliant tag” line. I have tried to change the tag multiple times and also to change the capacitor value but nothing changes. I am not able to read the tag as it is unable to detect NDef format but when I try to write I only get “store failed” on the result in TagWriter. I have also erased the tag to factory default so there is nothing that should prevent me from writing to it. Do you have any idea of what can be wrong or what has happened with my tags?

[Fabian_R]

Hello sir,

Thank you very much for the interest in using our products.

It is possible that when you are writing into the NTAG 5 memory, you aren't writing accordingly to the specification structure required for created an NDEF.

If the message structure isn't "understandable" when read by the NFC Reader, the application interpretates this as a custom NFC message.

In order to build your NDEF message, please take a look at the NFC Forum NDEF specification for Type 5 tags.