36.5.16.3 Tamper Freeze

For safety reasons, each I/O line can be configured to switch automatically in GPIO Input mode with pull-up in case of an external tamper event. This can be done by setting the TAMPEN bit in the PIO_CFGRx (or the S_PIO_CFGRx for a Secure I/O line). If the TAMPEN bit is set, the corresponding I/O line(s) switches automatically in General Purpose IO mode (GPIO) and Pull-Up is activated as long as the tamper event is detected. The “Tamper Freeze” is released when the tamper event is no longer present and frozen I/O line switch back to their applicative configuration automatically.