11.1.6 I/O Characteristics

The device features the following types of input/output (I/O) circuits:
  • GPIO I/Os with drive and slewrate control.
    • AUDIOCLK is a special case of GPIO type with hardwired DRIVE and SR controls.
      • For AUDIOCLK: DRIVE = 0 and SR = 1
  • HSIO I/Os with drive control only for the following lines:
    • SDMMC0: PA0, PA1, PA3, PA4, PA5, PA6, PA7, PA8, PA9, PA10, PA11
    • SDMMC1: PB22, PB23, PB24, PB25, PB26, PB27
    • SDMMC2: PC27, PC28, PC29, PC30, PC31, PD0
    • QSPI0, QSPI1: PB8, PB9, PB10, PB11, PB12, PB13, PB14, PB15, PB16, PB17, PB18, PB19, PB20
  • PIOBU I/Os with no drive and no slewrate control
Unless otherwise specified:
  • The following specifications apply to the GPIO, PIOBU and HSIO types.
  • VDD refers to the voltage of the associated power rail of the I/O line, as defined in the table Pin Description; for example, for PA12, VDD refers to the voltage applied on VDDSDMMC0.

For SDMMC lines in UHS I mode in the 1.8V range, the drive is controlled in the SDMMC user interface. In this case, drive configurations in PIO registers have no effect.

For any other SDMMC configuration, the GPIO drive configuration is applicable.

DRIVE and SLEWRATE are set in the PIO_CFGR register corresponding to the GPIO, with the DRVSTR and SR bits, respectively.