I'm looking for a way to send the unlock sequence from an Android phone to a Mifare tag from the Chinese manufacturer that makes the ones with a writable block 0.
I've been trying the connect + transceive methods, sending the 50 00 + 40 + 43 byte sequences. But that won't work.
I've tried the private transceive function (to get around error checking), but that won't work either. I get errors from the nfc service.
Has anyone successfully been able to send the unlock sequence to unlock block0?
This is not possible on an Android device. The proprietary commands for the Chinese MIFARE clone are 7 bits long, not a complete byte. The NFC implementations in Android devices (both the older with proprietary interface and the newer NFC Forum NCI compliant ones) work on payload buffers of complete bytes.