34.5.15.2.1 Physical Freeze
Setting PIO_IOFR.FPHY freezes the following fields (configured in PIO_CFGRx) of the Non-Secure I/O lines if the corresponding MSKx bit is set in PIO_MSKRx:
- FUNC: I/O Line Function
- DIR: Direction
- PUEN: Pull-Up Enable
- PDEN: Pull-Down Enable
- OPD: Open-Drain
- SCHMITT: Schmitt Trigger
- DRVSTR: Drive Strength
For Secure I/O lines, use the FPHY bit of the S_PIO_IOFRx and the S_PIO_MSKRx to freeze the fields above.
When the physical freeze is currently active on an I/O line, the PCFS flag is set when reading the PIO_CFGRx of the I/O line if the corresponding line is Non-Secure or the S_PIO_CFGRx if the I/O line is Secure.
Only a hardware reset can release fields listed above.