21.5.15.2.1 Physical Freeze

Setting PIO_IOFR.FPHY freezes the following fields (configured in PIO_CFGRx) of the 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
  • SLEWRATE: Slew Rate

For Privileged-Access mode I/O lines, use PIO_P_IOFRx.FPHY and the PIO_P_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 configured in User-Access mode or the PIO_P_CFGRx for the Privileged-Access mode I/O line .

Only a hardware reset can release fields listed above.