STM32F103系列的单片机一共有11个定时器，其中：
2个高级定时器、4个普通定时器、2个基本定时器、2个看门狗定时器、1个系统嘀嗒定时器
在除去看门狗定时器和系统滴答定时器的八个定时器中：
TIM1和TIM8是高级定时器，支持向上，向下，向上/向下这3种计数模式。
TIM2-TIM5是通用定时器，支持向上，向下，向上/向下这3种计数模式。
TIM6和TIM7是基本的定时器，支持向上这种计数模式。
timer.c
#include "timer.h"struct Tim3_Delay tim3_delay =
{
0,0,
0,0
};void TIM3_Int_Init(u16 arr,u16 psc)
{TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;NVIC_InitTypeDef NVIC_InitStructure;RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //时钟使能//定时器TIM8初始化TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值 TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值 Tout=（（arr+1）* (psc+1) )/72000TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_timTIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位TIM_ITConfig(TIM3,TIM_IT_Update,ENABLE ); //使能指定的TIM3中断,允许更新中断//中断优先级NVIC设置NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn; //TIM3中断NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; //先占优先级0级NVIC_InitStructure.NVIC_IRQChannelSubPriority = 3; //从优先级3级NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //IRQ通道被使能NVIC_Init(&NVIC_InitStructure); //初始化NVIC寄存器TIM_Cmd(TIM3, ENABLE); //使能TIMx }void TIM3_IRQHandler(void)
{ if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET) //检查TIM3更新中断发生与否{ tim3_delay.count_8ms ++;if(tim3_delay.count_8ms % 5 == 0)tim3_delay.count_40ms ++;if(tim3_delay.count_8ms % 100 == 0)tim3_delay.count_800ms ++; TIM_ClearITPendingBit(TIM3, TIM_IT_Update ); //清除TIMx更新中断标志 z }
} timer.h
#ifndef __TIMER_H
#define __TIMER_H#include "stm32f10x.h"
#include <sys.h> struct Tim3_Delay
{u32 count_8ms;u32 last_count_8ms;u32 count_40ms;u32 last_count_40ms;u32 count_800ms;u32 last_count_800ms;
};extern struct Tim3_Delay tim3_delay;void TIM3_Int_Init(u16 arr,u16 psc);
void TIM3_IRQHandler(void);#endif
key.c
#include "key.h"u16 KeyPressDown = 0x0000;//按下的键值
u16 KeyRelease = 0x0000;//弹起的键值
u16 LastKey = 0x0000;//上一次的键值 void Key_Init(void)
{GPIO_InitTypeDef GPIO_InitStructure;RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9 | GPIO_Pin_10 | GPIO_Pin_11 | GPIO_Pin_12;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOE,&GPIO_InitStructure);GPIO_WriteBit(GPIOE, GPIO_Pin_9 | GPIO_Pin_10 | GPIO_Pin_11 | GPIO_Pin_12, Bit_SET);KeyPressDown = 0;KeyRelease = 0;LastKey = 0;// Key_Port |= Key_Mask;//将按键对应的IO设置为输入状态
}//按键扫描，定时10ms执行一次
void Key_Scan(void)
{ //当前读取的键值 u16 CurrKey;//当按键1即A4按下11110xxxx//1110xxxx取反后00011111与上11110000得到00010000此时转换成16进制数字为0x10CurrKey = (~Key_Port) & Key_Mask; //11111111与上00010000得到0x10KeyPressDown = (~LastKey) & CurrKey; KeyRelease = LastKey & (~CurrKey); LastKey = CurrKey;
}key.h
#ifndef __KEY_H
#define __KEY_H #include "sys.h"#define Key1_Value 0x0200
#define Key2_Value 0x0400
#define Key3_Value 0x0800
#define Key4_Value 0x1000#define Key_Mask 0x1E00
#define Key_Port (GPIO_ReadInputData(GPIOE) & Key_Mask)//先将A4567四个位全部置高，如果按键按下，则那一位置0，与上Key_Mask则按下的那一按键置高，其余置0//如按键1，A4至低返回1110xxxx与上11110000得到按下的脚位，其余位保持和置低void Key_Init(void);
void Key_Scan(void);extern u16 KeyPressDown;//按下的键值
extern u16 KeyRelease;//弹起的键值
extern u16 LastKey;//上一次的键值 #endif
main.c
#include "SysTick.h"
#include "key.h"
#include "sys.h"
#include "timer.h"int main(void)
{ SysTick_Init(72); //延时函数初始化Key_Init();TIM3_Int_Init(79,7199); //===== （8ms）中断 计算公式如下：溢出时间（单位为 us）= ((arr+1)*(psc+1 ))/输入时钟频率（单位为 Mhz）；while(1){if(tim3_delay.last_count_8ms != tim3_delay.count_8ms){Key_Scan();tim3_delay.last_count_8ms = tim3_delay.count_8ms;}if(KeyPressDown == Key1_Value)//按键1{KeyPressDown = 0;}if(KeyPressDown == Key2_Value)//按键2{KeyPressDown = 0;}}
}
STM32F103C8T6基本功能代码_墨云景阳的博客-CSDN博客_stm32f103c8t6代码