2021-05-31
基于STM32ZET6的频率计（输入捕获）
#include "frequency.h"
#include "led.h"
#include "lcd.h"
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);
TIM_SelectInputTrigger(TIM3, TIM_TS_TI2FP2); //选择IC2为始终触发源
TIM_SelectSlaveMode(TIM3, TIM_SlaveMode_Reset);//TIM从模式：触发信号的上升沿重新初始化计数器和触发寄存器的更新事件
TIM_SelectMasterSlaveMode(TIM3, TIM_MasterSlaveMode_Enable); //启动定时器的被动触发
//中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn; //TIM3中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级2级
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //从优先级0级
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能
NVIC_Init(&NVIC_InitStructure); //根据NVIC_InitStruct中指定的参数初始化外设NVIC寄存器
TIM_ITConfig(TIM3,TIM_IT_CC2,ENABLE);//不能允许更新中断 ,允许CC2IE捕获中断
TIM_Cmd(TIM3,ENABLE); //使能定时器3
}
/***********************************************************************************************
************************************************************************************************/
u32 counter=0; // 每秒计数
u32 Frequency=0;
void TIM3_IRQHandler(void)
{
if (TIM_GetITStatus(TIM3, TIM_IT_CC2) == SET)
{
TIM_ClearITPendingBit(TIM3, TIM_IT_CC2); //清楚TIM的中断待处理位
counter = (u32)TIM_GetCapture2(TIM3);
Frequency =72000000/counter;
}
}
#ifndef __FREQUENCY_H
#define __FREQUENCY_H
#include "sys.h"
#include "stm32f10x_tim.h"
#include "stm32f10x.h"
#include "lcd.h"
void TIM3_counter_Init(u16 arr,u16 psc);
#endif
#include "led.h"
#include "delay.h"
#include "frequency.h"
#include "key.h"
#include "sys.h"
#include "lcd.h"
#include "usart.h"
#include "iic.h"
int main()
{
// u32 temp=0;
// vu8 key=0;
extern u32 Frequency; //输入捕获状态
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2);
delay_init(); //初始化延时函数
LED_Init(); //LED端口初始化
TIM3_counter_Init(0XFFFF,0); //72Mhz的频率计数，
uart_init(115200); //初始化串口
IIC_Init(); //初始化 IIC
KEY_Init();
LCD_Init();
POINT_COLOR=RED;
while(1)
{
LCD_ShowNum(30,60,Frequency,16,16); //显示一个数字
}
}