not able to program STM32h503rb

[kvganesh]

I have programmed all the pins of port A as GPIO input pins on my STM32H503rb. Now, I am not able to use the ST-link to reprogram anything into the microcontroller.
How do I reprogram it?

[kvganesh]

Port A has pins to JTAG and USB. I do not if that is stopping me from reprogramming. Is there a way to reset the pins to their default state

[AScha.3]

You have to set SWD debug, using PA13/14 , to have debug working.

Just to program/flash the cpu, connect CubeProgrammer "under reset" + hardware reset .

Needs a real st-link (with working nrst), or try with these settings to connect, while press/holding reset.

Other way would be: set boot0 hi, and connect to bootloader . (read in rm.)

[Tesla DeLorean]

If you strap BOOT0=HIGH your code will stop running, and the ROM based System Loader can be a safe harbour to get you back control. Use STM32 Cube Programmer to erase your code.

Connect-Under-Reset might help if you connected NRST to your debug header to facilitate that.