#include "stm32c0xx.h"

int main(void){
  RCC->IOPENR |= 1;

  GPIOA->MODER &= ~(3<<10);
  GPIOA->MODER |= (1<<10);

  while(1){
    GPIOA->ODR|=(1<<5);
    for(volatile int i=0; i<200000; i++);

    GPIOA->ODR&=~(1<<5);
    for(volatile int i=0; i<200000; i++);
  }
}