36.5.16.2.1 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.