Posted on May 17, 2011 at 12:42hi Friends,
I have to generate an timer interupt after every 0.005 ms for tim2 in stm32f103xx.
and i have to on LED for 5 second and off it for 5 second .
in practical case
LED ramain on for 2 second and remain off for 2 second .
can anyone give an idea where am i wrong? why LED is not on for 5 second and not off for 5 second .
is there any setting in TIM2 ?
my program :
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
#ifdef DEBUG
debug();
#endif
/* Configure the system clocks */
RCC_Configuration();
/* NVIC Configuration */
//NVIC_Configuration();
/* Configure PC0,PC1,PC2,PC3 output push-pull */
GPIO_DeInit(GPIOC);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //| GPIO_Pin_1| GPIO_Pin_2;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_Init(GPIOC, &GPIO_InitStructure); // PORT C as output
NVIC_DeInit();
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQChannel;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority =2;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x00;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* Time base configuration */
TIM_DeInit(TIM2);
TIM_TimeBaseStructure.TIM_Period =0xFFFF;
TIM_TimeBaseStructure.TIM_Prescaler =0x02;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
/* Clear TIM2 update pending flag */
TIM_ClearFlag(TIM2, TIM_FLAG_Update);
/* TIM IT enable */
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
while (1)
{
}
}
//interupt timer routine:
void TIM2_IRQHandler(void)
{
static unsigned long Timer_Value=0;
if(Flag==0)
{
GPIO_SetBits(GPIOC,GPIO_Pin_0);
if(++Timer_Value==1000000)
{
Timer_Value=0;
Flag=1;
}
}
else
{
GPIO_ResetBits(GPIOC,GPIO_Pin_0);
if(++Timer_Value==1000000)
{
Timer_Value=0;
Flag=0;
}
}
}
