STM32F4 Discovery und Keil uVision5 example Probleme

#include <stdio.h>

#include "STM32F4xx.h"

#include "GPIO_STM32F4xx.h"

volatile uint32_t msTicks;                      /* counts 1ms timeTicks       */

/*----------------------------------------------------------------------------

  SysTick_Handler

 *----------------------------------------------------------------------------*/

void SysTick_Handler(void) {

  msTicks++;

}

/*----------------------------------------------------------------------------

  delays number of tick Systicks (happens every 1 ms)

 *----------------------------------------------------------------------------*/

void Delay (uint32_t dlyTicks) {                                              

  uint32_t curTicks;

  curTicks = msTicks;

  while ((msTicks - curTicks) < dlyTicks);

}

/*----------------------------------------------------------------------------

  Main function

 *----------------------------------------------------------------------------*/

int main (void) {

  SystemCoreClockUpdate();                      /* Get Core Clock Frequency   */

  if (SysTick_Config(SystemCoreClock / 1000)) { /* SysTick 1 msec interrupts  */

    while (1);                                  /* Capture error              */

  }

  GPIO_PortClock   (GPIOD, true);

  GPIO_PinWrite    (GPIOD, 12, 0);

  GPIO_PinConfigure(GPIOD, 12,

                    GPIO_MODE_OUTPUT,

                    GPIO_OUTPUT_PUSH_PULL,

                    GPIO_OUTPUT_SPEED_50MHz,

                    GPIO_PULL_DOWN);

  GPIO_PinWrite(GPIOD, 12, 1);

  while(1) {

  }

}