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STM32H743 LSE pins as GPIO - not working

uprogc
Associate II

Hi,

I'm trying to use one from the following pins: PC 13,14,15, PI8, but not working. The code is CubeMX generated. clock for PORTC is enabled, no LSEON, no alternate function. I tried in OUTPUT_PP mode with pullup and without pullup. I think the PC14,15 is floating. ( I use I2S on PORTC, but that is working. ) Any solution for this ? Regards.

7 REPLIES 7
uprogc
Associate II

Anyone ?

uprogc
Associate II

I must change my 6L PCB design thanks to this problem !

Uwe Bonnes
Principal III

Start the program in a debugger and break into the program. Check the PORTC register settings against the reference manual. Keep in mind that PC13-15 has only limited source capability.

"Start the program in a debugger" - The PORTC settings are OK.

"Keep in mind that PC13-15 has" - I know. These pins are used in output mode for driving a logic CMOS IC.

Also read the GPIOs controlled by the RTC subchapter of RTC chapter in RM, read out and check the RTC registers.

Also check LSEON by reading it back.

JW

"Also check LSEON by reading it back." -- Done, No LSEON.

And the RTC registers?

And the GPIOC registers?

JW