stm32f103测量频率的代码
时间: 2023-07-03 11:08:25 浏览: 69
以下是使用STM32F103测量频率的基本代码:
```c
#include "stm32f10x.h"
#define TIMER_PRESCALER ((uint16_t)71) // 定时器预分频器
#define TIMER_PERIOD ((uint16_t)0xFFFF) // 定时器周期
uint16_t capture = 0;
uint32_t frequency = 0;
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_CC2) != RESET)
{
static uint16_t last_capture = 0;
capture = TIM_GetCapture2(TIM2);
frequency = (SystemCoreClock / TIMER_PRESCALER) / (capture - last_capture);
last_capture = capture;
TIM_ClearITPendingBit(TIM2, TIM_IT_CC2);
}
}
int main(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_ICInitTypeDef TIM_ICInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
GPIO_Init(GPIOA, &GPIO_InitStructure);
TIM_TimeBaseStructure.TIM_Period = TIMER_PERIOD;
TIM_TimeBaseStructure.TIM_Prescaler = TIMER_PRESCALER;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_ICInitStructure.TIM_Channel = TIM_Channel_2;
TIM_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising;
TIM_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI;
TIM_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1;
TIM_ICInitStructure.TIM_ICFilter = 0x0;
TIM_ICInit(TIM2, &TIM_ICInitStructure);
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
TIM_ITConfig(TIM2, TIM_IT_CC2, ENABLE);
TIM_Cmd(TIM2, ENABLE);
while (1)
{
// 读取频率值或进行其他操作
}
}
```
在这个例子中,我们使用了定时器 TIM2 来测量输入信号的频率。在中断处理程序中,我们计算了两个连续输入信号之间的时间差,并使用该时间差计算了输入信号的频率。因为我们使用 TIM2 来计数,所以我们需要配置定时器的时间基准和输入捕获通道。在这个例子中,我们将 PA1 配置为输入信号的引脚。