Posted on September 20, 2016 at 19:00Hello everyone,
A week's search didn't bring me very far, so I thought I should ask You guys. I have some experience using Arduino, but this is my first hard-core microcontroller project and so far the learning curve has been insane.
Anyway, I am using a stm32f4-discovery board, as an IDE I use Eclipse with the help of the HAL library. TIM3 is set up for base interrupts every 500ms for blinking two of the LEDs. I now want to set up TIM2 with the same type handle as TIM3 and attach an input capture on Channel 1 (PA0). I have connected PA0 and one of the LED pins. The goal is to get a counter value, which should be equivalent to 500ms.
The problem is that I never enter the input capture interrupt. Can anyone tell me what is wrong with the code? See below:
&sharpinclude <stdio.h>
&sharpinclude <stdlib.h>
&sharpinclude ''diag/Trace.h''
&sharpinclude <stm32f4xx_hal.h>
TIM_HandleTypeDef htim3;
TIM_HandleTypeDef htim2;
volatile uint32_t prev_time;
volatile uint32_t pulse_length;
volatile uint32_t count;
void InitializeLED()
{
__GPIOD_CLK_ENABLE();
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = GPIO_PIN_12|GPIO_PIN_14;
GPIO_InitStructure.Mode = GPIO_MODE_OUTPUT_PP;
GPIO_InitStructure.Speed = GPIO_SPEED_HIGH;
GPIO_InitStructure.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOD, &GPIO_InitStructure);
}
void InitializeTimer3()
{
__TIM3_CLK_ENABLE();
htim3.Instance = TIM3;
htim3.Init.Prescaler = 48000;
htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
htim3.Init.Period = 499;
htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim3.Init.RepetitionCounter = 0;
HAL_TIM_Base_Init(&htim3);
HAL_TIM_Base_Start_IT(&htim3);
HAL_NVIC_SetPriority(TIM3_IRQn, 1, 0);
HAL_NVIC_EnableIRQ(TIM3_IRQn);
}
void InitializeTimer2()
{
__HAL_RCC_GPIOA_CLK_ENABLE();
__TIM2_CLK_ENABLE();
TIM_IC_InitTypeDef sConfigIC;
htim2.Instance = TIM2;
htim2.Init.Prescaler = 48000;
htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
htim2.Init.Period = 65535;
htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
sConfigIC.ICPolarity = TIM_INPUTCHANNELPOLARITY_BOTHEDGE;
sConfigIC.ICSelection = TIM_ICSELECTION_DIRECTTI;
sConfigIC.ICPrescaler = TIM_ICPSC_DIV1;
sConfigIC.ICFilter = 0;
HAL_TIM_IC_ConfigChannel(&htim2, &sConfigIC, TIM_CHANNEL_1);
HAL_TIM_IC_Init(&htim2);
HAL_TIM_IC_Start_IT(&htim2, TIM_CHANNEL_1);
HAL_NVIC_SetPriority(TIM2_IRQn, 2, 0);
HAL_NVIC_EnableIRQ(TIM2_IRQn);
}
extern ''C'' void TIM3_IRQHandler()
{
HAL_TIM_IRQHandler(&htim3);
}
extern ''C'' void TIM2_IRQHandler()
{
HAL_TIM_IRQHandler(&htim2);
}
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_12|GPIO_PIN_14);
}
void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef *htim)
{
pulse_length = __HAL_TIM_GetCompare(&htim2, TIM_CHANNEL_1); //read TIM2 channel 1 capture value
__HAL_TIM_SetCounter(&htim2, 0); //reset counter after input capture interrupt occurs
}
void main()
{
InitializeLED();
InitializeTimer3();
InitializeTimer2();
while(1)
{
count = __HAL_TIM_GetCounter(&htim2);
}
}
#hal-library #input-capture
