I am trying to write to the configuration area of an ST25DV04KC NFC chip using I2C. I am able to read and write to the user area. I am able to present the default password (8 zeros, 0x09, 8 zeros) and the SSO_Dyn register switches from 0x00 to 0x01, indicating that I have entered a secure session. It also switches back to 0x00 if I present a bad password.
With the SSO_Dyn register reading 0x01, I then write with addressing 0xAE the following bytes: 0x00, 0x05, 0x08. The message doesn't receive an ACK and the value doesn't change. I can read and write everything OK using the ST25 tap app on my phone. I am also able to read the configuration registers over I2C. A dump of my configuration registers taken over I2C is below.
What could I be doing wrong?
Thanks,
David
CFG: 0x0000: 0x11
CFG: 0x0001: 0x0c
CFG: 0x0002: 0x01
CFG: 0x0003: 0x00
CFG: 0x0004: 0x00
CFG: 0x0005: 0x04
CFG: 0x0006: 0x00
CFG: 0x0007: 0x07
CFG: 0x0008: 0x00
CFG: 0x0009: 0x0c
CFG: 0x000a: 0x00
CFG: 0x000b: 0x00
CFG: 0x000c: 0x00
CFG: 0x000d: 0x00
CFG: 0x000e: 0x1a
CFG: 0x000f: 0x00
CFG: 0x0010: 0x00
CFG: 0x0011: 0x00
CFG: 0x0012: 0x00
CFG: 0x0013: 0x00
CFG: 0x0014: 0x7f
CFG: 0x0015: 0x00
CFG: 0x0016: 0x03
