after programming, stm32 needs powercycle to reset.

[Strooom]

When I program my STM32WLE5  using STM32CubeProgrammer and UART, a simple push on the reset button does not reset the MCU.

I always need to power-cycle it.

Why is the reset-pin not working, or why does it not start the application ? Is there a way to configure the option bytes to solve this ?

More info : I am doing this on a custom board, which has a USB-UART (CP2102N). Whenever the device comes out of reset, I check for the USB voltage, and if present, I jump to the bootloader.

After programming I remove the USB and reset the device again which should start the application. But until now this second reset does not work and I need to powercycle the MCU.

[Strooom · Accepted solution]

Using the debugger, I've learned that this was caused by a sw-error : the IO detecting the VBUS voltage was not properly initialized, which caused the code to jump to to bootloader after a system reset (pulling RST pin low), and not after a power-cycle.

When correctly initializing the IO, both resets work as they should.