STM32F103RCT6实现数字频率计的代码
时间: 2024-06-08 11:12:06 浏览: 6
以下是STM32F103RCT6实现数字频率计的代码,代码中使用了TIM2定时器和输入捕获功能来测量输入信号的周期,从而计算出输入信号的频率。代码中使用了PA0引脚作为输入信号的引脚。
```c
#include "stm32f10x.h"
uint16_t capture = 0;
uint16_t last_capture = 0;
uint32_t period = 0;
uint32_t frequency = 0;
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)
{
TIM_ClearITPendingBit(TIM2, TIM_IT_CC1);
last_capture = capture;
capture = TIM_GetCapture1(TIM2);
if (last_capture > capture)
{
period = (0xFFFF - last_capture) + capture + 1;
}
else
{
period = capture - last_capture;
}
frequency = SystemCoreClock / period;
}
}
void TIM2_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_ICInitTypeDef TIM_ICInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_Init(GPIOA, &GPIO_InitStructure);
TIM_TimeBaseStructure.TIM_Period = 0xFFFF;
TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_ICInitStructure.TIM_Channel = TIM_Channel_1;
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 = 0x00;
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_CC1, ENABLE);
}
int main(void)
{
TIM2_Configuration();
while (1)
{
// 计算出来的频率可以在这里进行处理
}
}
```
在代码中,TIM2_IRQHandler()函数是TIM2的中断服务函数,用来计算输入信号的周期和频率。TIM2_Configuration()函数用来配置TIM2定时器和输入捕获功能。在主函数中可以通过frequency变量获取输入信号的频率,然后进行进一步的处理。注意,为了防止计算频率时出现溢出,TIM2的自动重载寄存器需要设置为0xFFFF,同时需要在中断服务函数中处理定时器溢出的情况。