How to downgrade Firmware(PN557) on Android device?

[HoangNg_datalogic]

My Android device with a PN557 chip was updated from Android 11 to Android 13. However, after I rolled back to Android 11, the NFC stopped working.

I noticed that the NFC chip cannot be downgraded to a version with a smaller major number than it currently has. I would like to ask if there is a way to force the NFC chip to downgrade to a version with a smaller major number.

Thanks,

Hoang

[HoangNg_datalogic]

Hi @danielchen 

I have implemented the NFC according to the porting document for Android, and it worked. We are just facing the issue with the firmware version right now. What I want to ask is: the firmware download process involves a few checks and then transmits the firmware package to the NFC chip, correct? Then the chip performs the upgrade or downgrade and notifies the result.

Is there any documentation available that can help me understand how the PN557 or PN553 works?

Thanks,
Hoang

[danielchen]

sorry, there is no document about this.   In the firmware, it will check the target version number when you are trying to update it.  If the target version number is smaller than the current version,  then this update will be refused.

Regards

Daniel

[danielchen]

Hi HoangNg:

PN557 is not a mass market product , I would suggest you contact your Disty FAE or local FAE for support.

But as far as I know,  there is not a way to force NFC chip to downgrade to a version with a smaller major number.

Regards

Daniel