Implementation/myGPIO.c
void GPIO_pupd(GPIO_TypeDef *port, int pin, int pupd)
{
	(port->PUPDR) &= ~(3UL<<(2*pin));
	(port->PUPDR) |= (pupd<<(2*pin));
}
// GPIO pin pullup-pulldown selection

GPIO pin pullup-pulldown selection
GPIO pin pullup - pulldown selection
void GPIO_pupd(GPIO_TypeDef *port, int pin, int pupd)
{
	(port->PUPDR) &= ~(3UL<<(2*pin));
	(port->PUPDR) |= (pupd<<(2*pin));
}
void GPIO_pupd ( GPIO_TypeDef * port , int pin , int pupd ) { ( port -> PUPDR ) &= ~ ( 3UL << ( 2 * pin ) ) ; ( port -> PUPDR ) |= ( pupd << ( 2 * pin ) ) ; }
GPIO pin pullup-pulldown selection
GPIO pin pullup - pulldown selection