Perhaps this is NFC question instead of B4X question.
I have a blank NFC card with TagTechnlogy: android.nfc.tech.NfcA, android.nfc.tech.MifareClassic, and android.nfc.tech.NdefFormatable.
I modified from Erel's program below, trying to write to this blank card but found nothing is written to the card. Any hints?
www.b4x.com
The code changed is as below, where gnfc_mode = 2 for writting = 1 for reading.
The program "WriteNdef" runs but no data written to the card.
If I use other NFC tool to write data one time, then I could read and write to that card.
I have a blank NFC card with TagTechnlogy: android.nfc.tech.NfcA, android.nfc.tech.MifareClassic, and android.nfc.tech.NdefFormatable.
I modified from Erel's program below, trying to write to this blank card but found nothing is written to the card. Any hints?
NFC - Reading and Writing
NFC v2.00 adds support for low level access to the NFC features. This allows reading and writing from NFC tags. The NFC library provides three features: - Reading Ndef tags based intent filters: Reading NDEF data from NFC tags - Sending data between two devices (Android Beam)...

The code changed is as below, where gnfc_mode = 2 for writting = 1 for reading.
B4X:
Dim techs As List = gnfc.GetTechList(intentstart)
If gnfc_mode = 1 And techs.IndexOf("android.nfc.tech.Ndef") > -1 Then
gnfctech.Initialize("NFCTag", "android.nfc.tech.Ndef" , intentstart)
gnfctech.Connect
else if gnfc_mode = 2 And techs.IndexOf("android.nfc.tech.Ndef") > -1 Then
gnfctech.Initialize("NFCTag", "android.nfc.tech.Ndef" , intentstart)
gnfctech.Connect
else if gnfc_mode = 2 And techs.IndexOf("android.nfc.tech.NfcA") > -1 Then
gnfctech.Initialize("NFCTag", "android.nfc.tech.NfcA" , intentstart)
gnfctech.Connect
else if gnfc_mode = 2 And techs.IndexOf("android.nfc.tech.NdefFormatable") > -1 Then
gnfctech.Initialize("NFCTag", "android.nfc.tech.NdefFormatable" , intentstart)
gnfctech.Connect
The program "WriteNdef" runs but no data written to the card.
If I use other NFC tool to write data one time, then I could read and write to that card.