I'm working on Time6 Interrupt for STM32F103zet6. I intended to creat a 200ms timer interrupt and when the timer is up, display something.Please see my code below.

/* TIM6 Periph clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM6, ENABLE);

/*Timer6 configuration------------------------------------------------*/
TIM_PrescalerConfig(TIM6, 223, TIM_PSCReloadMode_Update);//0.25Mhz=56M/224 0.125Mhz=56M/448
TIM_SetAutoreload(TIM6, 50000);//50000=200ms timer
TIM_Cmd(TIM6, ENABLE); /* TIM6 enable counter */

/* Enable TIM6 Update interrupt */
TIM_ITConfig(TIM6, TIM_IT_Update, ENABLE);

/* Enable the TIM6 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM6_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

void TIM6_IRQHandler(void)
{
TIM_ClearITPendingBit(TIM6, TIM_IT_Update);
Timer200msFlag = !Timer200msFlag;
if(Timer200msFlag == 1)
{
GPIO_WriteBit(GPIOF, GPIO_Pin_6, Bit_SET);
}
else
{
GPIO_WriteBit(GPIOF, GPIO_Pin_6, Bit_RESET);
}
}
void main(void)
{
while(Timer200msFlag ==0);
Display();
}
I can see LED(port F6) flashes @200ms speed and Timer200msFlag toggles, but on the main function,Display() function is never excuted.

Thanks for your help!