STM32：频率计(输入捕获模式).7z

#include "counter.h" #include "stdio.h" #include "usart.h" /*********************************************************************************************** //上升沿捕获 ************************************************************************************************/ TIM_ICInitTypeDef TIM3_ICInitStructure; void TIM3_counter_Init(u16 arr,u16 psc) { GPIO_InitTypeDef GPIO_InitStructure; TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; NVIC_InitTypeDef NVIC_InitStructure; RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能TIM5时钟 RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7; //PA7 清除之前设置 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; //PA7 浮空输入 GPIO_Init(GPIOA, &GPIO_InitStructure); GPIO_ResetBits(GPIOA,GPIO_Pin_7); //PA7 下拉 //初始化定时器5 TIM5 TIM_TimeBaseStructure.TIM_Period = arr; //设定计数器自动重装值 TIM_TimeBaseStructure.TIM_Prescaler =psc; //预分频器 TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式 TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位 //初始化TIM5输入捕获参数 TIM3_ICInitStructure.TIM_Channel = TIM_Channel_2; // 选择输入端 IC1映射到TI1上 TIM3_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获 TIM3_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上 TIM3_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //配置输入分频,不分频 TIM3_ICInitStructure.TIM_ICFilter = 0x00; //IC1F=0000 配置输入滤波器 不滤波 TIM_ICInit(TIM3, &TIM3_ICInitStructure);