Posted on December 11, 2012 at 09:30Hello all experts,
I configured the TIM2 in my STM32F4 discovery board such that it gives me interrupts every 50ms. The code is as follows.
*********************************
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
{
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
GPIO_ToggleBits(GPIOA, GPIO_Pin_5);
}}
*********************************
void INTTIM_Config(uint16_t numOfMilleseconds)
{
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable the TIM2 gloabal Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* TIM2 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = (500*numOfMilleseconds) - 1; // 1 MHz down to 1 KHz (1 ms)
//TIM_TimeBaseStructure.TIM_Prescaler = 84 - 1; // 24 MHz Clock down to 1 MHz (adjust per your clock)
TIM_TimeBaseStructure.TIM_Prescaler = 168-1; //168MHz Clock should be down to 1MHz
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
/* TIM IT enable */
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
}
*******************************************
int main(void)
{
GPIO_config();
INTTIM_Config(50);
while (1)
{
}
}
****************************************************
- I'm checking the PA5 signal with the oscilloscope and what I expect is to toggle the signal in each 50ms interval.
- My problem is when I check this with the scope, I see that when I run TIM_Cmd(TIM2, ENABLE); command, program jumps to the interrupt routine.
- As a summary, interrupt routine is executed when I enable the time.
Can someone please help me with this issue.
Thank you for spending your valuable time.
Regards,
Thilina
#adc-and-tim2-interrupt. #discovery-board
