STM32H745I_DISCO GPIO not working on PC3_C

[ricks]

We are using the STM32H745I_DISCO and a custom daughterboard.  We use the Arduino Connectors to interface to our daughterboard.  One of the signals on CN7 pin 6 is default jumpered to PC3_C on the processor.  We cannot get it to work at a digital push-pull GPIO.  All of the other GPIOs work as we expected. We have checked our code against another similar case and it appears to be the same.  We are wondering if this might be because PC3_C cannot be used as a GPIO and is only analog or the following alternate functions listed in the STM32H745xI/G datasheet.

C1SLEEP, DFSDM1_DATIN1, SPI2_MOSI/I2S2_SDO, OTG_HS_ULPI_NXT, ETH_MII_TX_CLK, FMC_SDCKE0, EVENTOUT 

Can someone confirm if the PC3_C can be used as a GPIO or not, and if it can, anything we might be missing to get it to work.  Also, what is the "_C" meant to differentiate (from say the other PC3 function).

 

Thanks

[ricks]

We think we figured how to use it as GPIO.  We needed the command:

HAL_SYSCFG_AnalogSwitchConfig(SYSCFG_SWITCH_PC3,SYSCFG_SWITCH_PC3_CLOSE)