简单介绍
下面的定时器都具有输入捕获能力：
外部计数频率计
查看另一篇文章：https://qq742971636.blog.csdn.net/article/details/131471539
外部计数频率计的缺点：需要两个定时器配合，最高能测量的频率是否有限制我没具体尝试。
基于捕获的频率计的缺点：最高能测量的频率有限制。
TIM2 频率计 捕获
TIM3_CH1 PWM PA6 10KHZ。
输入到TIM2_CH1 PA0。
#include "sys.h"
#include "usart.h"
//定时器2通道1输入捕获配置
TIM_ICInitTypeDef TIM2_ICInitStructure;
void TIM2_Cap_Init(u16 arr, u16 psc) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //使能TIM2时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //PA0 清除之前设置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_ResetBits(GPIOA, GPIO_Pin_0); //PA0 下拉
//初始化定时器5 TIM2
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(TIM2, &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TIM2输入捕获参数
TIM2_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01 选择输入端 IC1映射到TI1上
TIM2_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获
TIM2_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上
TIM2_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //配置输入分频,不分频
TIM2_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
TIM_ICInit(TIM2, &TIM2_ICInitStructure);
//中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn; //TIM2中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //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(TIM2, TIM_IT_Update | TIM_IT_CC1, ENABLE);//允许更新中断 ,允许CC1IE捕获中断
TIM_Cmd(TIM2, ENABLE); //使能定时器5
//TIM_OC1PolarityConfig(TIM2, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获 随时可改捕获极性
}
u8 cap_status = 0; //输入捕获状态
u16 cap_value; //输入捕获值
u32 cap_value_cnt = 0;//输入捕获值计数器
u32 freq;
//定时器5中断服务程序
void TIM2_IRQHandler(void) {
if ((cap_status & 0X80) == 0)//还未成功捕获
{
if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
if (cap_status & 0X40)//已经捕获到高电平了
{
cap_value_cnt++;//定时器溢出一次
}
}
if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)//捕获1发生捕获事件
{
if (cap_status & 0X40) //在"标记捕获到了上升沿"之后，再次捕获到了上升沿
{
cap_status |= 0X80; //标记成功捕获到一次高电平脉宽
cap_value = TIM_GetCapture1(TIM2);
//TIM_OC1PolarityConfig(TIM2, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获
} else //还未开始,第一次捕获上升沿
{
cap_status = 0; //清空
cap_value = 0;
TIM_SetCounter(TIM2, 0);
cap_status |= 0X40; //标记捕获到了上升沿
//TIM_OC1PolarityConfig(TIM2, TIM_ICPolarity_Falling); //CC1P=1 设置为下降沿捕获
}
}
}
TIM_ClearITPendingBit(TIM2, TIM_IT_CC1 | TIM_IT_Update); //清除中断标志位
}
//TIM3 PWM部分初始化
//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
void TIM3_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能定时器3时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
//设置该引脚为复用输出功能
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7; //TIM3_CH1 TIM3_CH2
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIO
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1; //TIM3_CH3 TIM3_CH4
GPIO_Init(GPIOB, &GPIO_InitStructure);//初始化GPIO
//初始化TIM3
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
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //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
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC1Init(TIM3, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC1
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式2
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC2Init(TIM3, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式3
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC3Init(TIM3, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC3
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式4
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC4Init(TIM3, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC4
TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能TIM3在CCR1上的预装载寄存器
TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
TIM_OC3PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能TIM3在CCR3上的预装载寄存器
TIM_OC4PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能TIM3在CCR4上的预装载寄存器
TIM_Cmd(TIM3, ENABLE); //使能TIM3
}
int main(void) {
u32 temp = 0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* 设置NVIC中断分组2:2位抢占优先级，2位响应优先级 */
delay_init(); /* 延时函数初始化 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE); /* 关闭jtag，使能SWD，可以用SWD模式调试 */
delay_ms(500); /* 等待稳定 */
uart_init(115200);
TIM2_Cap_Init(0XFFFF, 72 - 1); //以1Mhz的频率计数
TIM3_PWM_Init( 7200, 0 ); /* 10KHz */
TIM_SetCompare1( TIM3, 3600 );
TIM_SetCompare2( TIM3, 3600 );
TIM_SetCompare3( TIM3, 3600 );
TIM_SetCompare4( TIM3, 3600 );
while (1) {
delay_ms(100);
if (cap_status & 0X80)//成功捕获到了一次上升沿
{
temp = cap_value_cnt * 65536 + cap_value;//两次捕获之间的时间差
printf("HIGH+LOW:%d us\r\n", temp);//打印总的高点平时间
freq = 1000000 / temp;//计算频率
printf("freq:%d Hz\r\n", freq);//打印频率
cap_status = 0;//开启下一次捕获
}
}
}
TIM3 频率计 捕获
TIM3_CH1 PA6 捕获输入。
TIM2_CH2 PWM 10khz输出。
接起来看到：
#include "sys.h"
#include "usart.h"
//定时器2通道1输入捕获配置
TIM_ICInitTypeDef TIM3_ICInitStructure;
void TIM3_Cap_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TIM3时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //PA0 清除之前设置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_ResetBits(GPIOA, GPIO_Pin_0); //PA0 下拉
//初始化定时器5 TIM3
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TIM3输入捕获参数
TIM3_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01 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);
//中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM3_IRQn; //TIM3中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //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_Update | TIM_IT_CC1, ENABLE);//允许更新中断 ,允许CC1IE捕获中断
TIM_Cmd(TIM3, ENABLE); //使能定时器5
//TIM_OC1PolarityConfig(TIM3, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获 随时可改捕获极性
}
u8 cap_status = 0; //输入捕获状态
u16 cap_value; //输入捕获值
u32 cap_value_cnt = 0;//输入捕获值计数器
u32 freq;
//定时器5中断服务程序
void TIM3_IRQHandler(void) {
if ((cap_status & 0X80) == 0)//还未成功捕获
{
if (TIM_GetITStatus(TIM3, TIM_IT_Update) != RESET) {
if (cap_status & 0X40)//已经捕获到高电平了
{
cap_value_cnt++;//定时器溢出一次
}
}
if (TIM_GetITStatus(TIM3, TIM_IT_CC1) != RESET)//捕获1发生捕获事件
{
if (cap_status & 0X40) //在"标记捕获到了上升沿"之后，再次捕获到了上升沿
{
cap_status |= 0X80; //标记成功捕获到一次高电平脉宽
cap_value = TIM_GetCapture1(TIM3);
//TIM_OC1PolarityConfig(TIM3, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获
} else //还未开始,第一次捕获上升沿
{
cap_status = 0; //清空
cap_value = 0;
TIM_SetCounter(TIM3, 0);
cap_status |= 0X40; //标记捕获到了上升沿
//TIM_OC1PolarityConfig(TIM3, TIM_ICPolarity_Falling); //CC1P=1 设置为下降沿捕获
}
}
}
TIM_ClearITPendingBit(TIM3, TIM_IT_CC1 | TIM_IT_Update); //清除中断标志位
}
//TIM2 PWM部分初始化
//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
//配置7路PWM
void TIM2_PWM_Init(u16 arr, u16 psc) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //使能定时器2时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
//设置该引脚为复用输出功能
GPIO_InitStructure.GPIO_Pin =
GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3; //TIM2_CH1 TIM2_CH2 TIM2_CH3 TIM2_CH4
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIO
//初始化TIM2
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
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //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(TIM2, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC1Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC1
TIM_OC2Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC2
TIM_OC3Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC3
TIM_OC4Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC4
TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR1上的预装载寄存器
TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR2上的预装载寄存器
TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR3上的预装载寄存器
TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR4上的预装载寄存器
TIM_Cmd(TIM2, ENABLE); //使能TIM2
}
int main(void) {
u32 temp = 0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* 设置NVIC中断分组2:2位抢占优先级，2位响应优先级 */
delay_init(); /* 延时函数初始化 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE); /* 关闭jtag，使能SWD，可以用SWD模式调试 */
delay_ms(500); /* 等待稳定 */
uart_init(115200);
TIM3_Cap_Init(0XFFFF, 72 - 1); //以1Mhz的频率计数
TIM2_PWM_Init(7200, 0); /* 10KHz */
TIM_SetCompare1(TIM2, 2000);//PA0
TIM_SetCompare2(TIM2, 2000);
TIM_SetCompare3(TIM2, 2000);
TIM_SetCompare4(TIM2, 2000);
while (1) {
delay_ms(100);
if (cap_status & 0X80)//成功捕获到了一次上升沿
{
temp = cap_value_cnt * 65536 + cap_value;//两次捕获之间的时间差
printf("HIGH+LOW:%d us\r\n", temp);//打印总的高点平时间
freq = 1000000 / temp;//计算频率
printf("freq:%d Hz\r\n", freq);//打印频率
cap_status = 0;//开启下一次捕获
}
}
}
TIM4 频率计 捕获
TIM4_CH1 PB6 捕获输入。
TIM2_CH2 PWM 10khz输出。
接起来看到：
#include "sys.h"
#include "usart.h"
//定时器2通道1输入捕获配置
TIM_ICInitTypeDef TIM4_ICInitStructure;
void TIM4_Cap_Init(u16 arr, u16 psc) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE); //使能TIM4时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6; //PA0 清除之前设置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_ResetBits(GPIOA, GPIO_Pin_0); //PA0 下拉
//初始化定时器5 TIM4
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(TIM4, &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TIM4输入捕获参数
TIM4_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01 选择输入端 IC1映射到TI1上
TIM4_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获
TIM4_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上
TIM4_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //配置输入分频,不分频
TIM4_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
TIM_ICInit(TIM4, &TIM4_ICInitStructure);
//中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM4_IRQn; //TIM4中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //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(TIM4, TIM_IT_Update | TIM_IT_CC1, ENABLE);//允许更新中断 ,允许CC1IE捕获中断
TIM_Cmd(TIM4, ENABLE); //使能定时器5
//TIM_OC1PolarityConfig(TIM4, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获 随时可改捕获极性
}
u8 cap_status = 0; //输入捕获状态
u16 cap_value; //输入捕获值
u32 cap_value_cnt = 0;//输入捕获值计数器
u32 freq;
//定时器5中断服务程序
void TIM4_IRQHandler(void) {
if ((cap_status & 0X80) == 0)//还未成功捕获
{
if (TIM_GetITStatus(TIM4, TIM_IT_Update) != RESET) {
if (cap_status & 0X40)//已经捕获到高电平了
{
cap_value_cnt++;//定时器溢出一次
}
}
if (TIM_GetITStatus(TIM4, TIM_IT_CC1) != RESET)//捕获1发生捕获事件
{
if (cap_status & 0X40) //在"标记捕获到了上升沿"之后，再次捕获到了上升沿
{
cap_status |= 0X80; //标记成功捕获到一次高电平脉宽
cap_value = TIM_GetCapture1(TIM4);
//TIM_OC1PolarityConfig(TIM4, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获
} else //还未开始,第一次捕获上升沿
{
cap_status = 0; //清空
cap_value = 0;
TIM_SetCounter(TIM4, 0);
cap_status |= 0X40; //标记捕获到了上升沿
//TIM_OC1PolarityConfig(TIM4, TIM_ICPolarity_Falling); //CC1P=1 设置为下降沿捕获
}
}
}
TIM_ClearITPendingBit(TIM4, TIM_IT_CC1 | TIM_IT_Update); //清除中断标志位
}
//TIM2 PWM部分初始化
//PWM输出初始化
//arr：自动重装值
//psc：时钟预分频数
//配置7路PWM
void TIM2_PWM_Init(u16 arr, u16 psc) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); //使能定时器2时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
//设置该引脚为复用输出功能
GPIO_InitStructure.GPIO_Pin =
GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3; //TIM2_CH1 TIM2_CH2 TIM2_CH3 TIM2_CH4
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化GPIO
//初始化TIM2
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
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //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(TIM2, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
TIM_OC1Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC1
TIM_OC2Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC2
TIM_OC3Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC3
TIM_OC4Init(TIM2, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM2 OC4
TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR1上的预装载寄存器
TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR2上的预装载寄存器
TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR3上的预装载寄存器
TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Enable); //使能TIM2在CCR4上的预装载寄存器
TIM_Cmd(TIM2, ENABLE); //使能TIM2
}
int main(void) {
u32 temp = 0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* 设置NVIC中断分组2:2位抢占优先级，2位响应优先级 */
delay_init(); /* 延时函数初始化 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE); /* 关闭jtag，使能SWD，可以用SWD模式调试 */
delay_ms(500); /* 等待稳定 */
uart_init(115200);
TIM4_Cap_Init(0XFFFF, 72 - 1); //以1Mhz的频率计数
TIM2_PWM_Init(7200, 0); /* 10KHz */
TIM_SetCompare1(TIM2, 2000);//PB6
TIM_SetCompare2(TIM2, 2000);
TIM_SetCompare3(TIM2, 2000);
TIM_SetCompare4(TIM2, 2000);
while (1) {
delay_ms(100);
if (cap_status & 0X80)//成功捕获到了一次上升沿
{
temp = cap_value_cnt * 65536 + cap_value;//两次捕获之间的时间差
printf("HIGH+LOW:%d us\r\n", temp);//打印总的高点平时间
freq = 1000000 / temp;//计算频率
printf("freq:%d Hz\r\n", freq);//打印频率
cap_status = 0;//开启下一次捕获
}
}
}
TIM5 频率计 捕获
#include "sys.h"
#include "usart.h"
//定时器5通道1输入捕获配置
TIM_ICInitTypeDef TIM5_ICInitStructure;
void TIM5_Cap_Init(u16 arr, u16 psc) {
GPIO_InitTypeDef GPIO_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE); //使能TIM5时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE); //使能GPIOA时钟
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; //PA0 清除之前设置
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPD; //PA0 输入
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_ResetBits(GPIOA, GPIO_Pin_0); //PA0 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(TIM5, &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
TIM5_ICInitStructure.TIM_Channel = TIM_Channel_1; //CC1S=01 选择输入端 IC1映射到TI1上
TIM5_ICInitStructure.TIM_ICPolarity = TIM_ICPolarity_Rising; //上升沿捕获
TIM5_ICInitStructure.TIM_ICSelection = TIM_ICSelection_DirectTI; //映射到TI1上
TIM5_ICInitStructure.TIM_ICPrescaler = TIM_ICPSC_DIV1; //配置输入分频,不分频
TIM5_ICInitStructure.TIM_ICFilter = 0x00;//IC1F=0000 配置输入滤波器 不滤波
TIM_ICInit(TIM5, &TIM5_ICInitStructure);
//中断分组初始化
NVIC_InitStructure.NVIC_IRQChannel = TIM5_IRQn; //TIM5中断
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2; //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(TIM5, TIM_IT_Update | TIM_IT_CC1, ENABLE);//允许更新中断 ,允许CC1IE捕获中断
TIM_Cmd(TIM5, ENABLE); //使能定时器5
//TIM_OC1PolarityConfig(TIM5, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获 随时可改捕获极性
}
u8 cap_status = 0; //输入捕获状态
u16 cap_value; //输入捕获值
u32 cap_value_cnt = 0;//输入捕获值计数器
u32 freq;
//定时器5中断服务程序
void TIM5_IRQHandler(void) {
if ((cap_status & 0X80) == 0)//还未成功捕获
{
if (TIM_GetITStatus(TIM5, TIM_IT_Update) != RESET) {
if (cap_status & 0X40)//已经捕获到高电平了
{
cap_value_cnt++;//定时器溢出一次
}
}
if (TIM_GetITStatus(TIM5, TIM_IT_CC1) != RESET)//捕获1发生捕获事件
{
if (cap_status & 0X40) //在"标记捕获到了上升沿"之后，再次捕获到了上升沿
{
cap_status |= 0X80; //标记成功捕获到一次高电平脉宽
cap_value = TIM_GetCapture1(TIM5);
//TIM_OC1PolarityConfig(TIM5, TIM_ICPolarity_Rising); //CC1P=0 设置为上升沿捕获
} else //还未开始,第一次捕获上升沿
{
cap_status = 0; //清空
cap_value = 0;
TIM_SetCounter(TIM5, 0);
cap_status |= 0X40; //标记捕获到了上升沿
//TIM_OC1PolarityConfig(TIM5, TIM_ICPolarity_Falling); //CC1P=1 设置为下降沿捕获
}
}
}
TIM_ClearITPendingBit(TIM5, TIM_IT_CC1 | TIM_IT_Update); //清除中断标志位
}
int main(void) {
u32 temp = 0;
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); /* 设置NVIC中断分组2:2位抢占优先级，2位响应优先级 */
delay_init(); /* 延时函数初始化 */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE); /* 关闭jtag，使能SWD，可以用SWD模式调试 */
delay_ms(500); /* 等待稳定 */
uart_init(115200);
TIM5_Cap_Init(0XFFFF, 72 - 1); //以1Mhz的频率计数
while (1) {
delay_ms(10);
if (cap_status & 0X80)//成功捕获到了一次上升沿
{
temp = cap_value_cnt * 65536 + cap_value;//两次捕获之间的时间差
printf("HIGH+LOW:%d us\r\n", temp);//打印总的高点平时间
freq = 1000000 / temp;//计算频率
printf("freq:%d Hz\r\n", freq);//打印频率
cap_status = 0;//开启下一次捕获
}
}
}