[ST25DVxxK] How to disable mailbox/fast transfer mode with I2C ?

[VGava]

Using RF I am able to activate mailbox/fast transfer mode using this process :

• Present password
• Write static GPO => replace former GPO with 0xB0
• Write MB Mode => 1
• Write MB CTRL Dyn => 1

Now I need to deactivate the mailbox with I2C. I am following this process :

• Present password
• Write static GPO => former GPO
• Write MB Mode => 0

I can see the values are right in the register. However whenever I approach the ST25 app on Android, it says the mailbox is still activated, preventing me from being able to write anything on the EEPROM (error returned : 0x0f)

Is there something I am missing ?

Thanks

[JL. Lebon · Accepted solution]

​Hello,

There is 3 different way to disable fast transfer mode from I2C interface:

1. remove VCC power supply. This automatically disable the fast transfer mode.
2. write 00 in MB_CTRL_dyn register. This disable the fast transfer mode
3. write 00 in MB_MODE configuration. This automatically sets the GPO_CTRL_Dyn register MB_EN bit to 0 and disallow reactivation of fast transfer mode by setting this MB_CTRL_Dyn to 01.

So what you are doing from I2C side sounds good to me.

Which version of ST25 app are you using?

Are you removing the phone from the tag when programming by I2C ?

When you put back the phone on the tag, do you make any action in the app ?

Best regards.