29.5.2 Power Management
During Reset, all PORT lines are configured as inputs with input buffers, output buffers and pull disabled.
When the device is set to the BACKUP sleep mode, even if the PORT configuration registers and input synchronizers will lose their contents (these will not be restored when PORT is powered up again), the latches in the pads will keep their current configuration, such as the output value and pull settings. Refer to the Power Manager documentation for more features related to the I/O lines configuration in and out of BACKUP mode.
The PORT peripheral will continue operating in any sleep mode where its source clock is running.
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