STM32有四个通用定时器,现在介绍TIM4输出4路PWM的方法
TIM4可以选择不用重映射
或者重映射
一、没有重映射
下面展示主要的time.c、main.c函数的代码
#include "timer.h"
void TIM4_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);//使能定时器4时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
GPIO_PinRemapConfig(GPIO_Remap_TIM4, ENABLE); //TIM4重映射
//GPIO配置
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7|GPIO_Pin_8|GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//初始化TIM4
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(TIM4, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
//配置TIM4的PWM
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
//CH1
TIM_OC1Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC1PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH12
TIM_OC2Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC2PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH13
TIM_OC3Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC3PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH14
TIM_OC4Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC4PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
TIM_Cmd(TIM4, ENABLE); //使能TIM4
}
#include "timer.h"
int main(void)
{
delay_init(); //延时函数初始化
TIM4_PWM_Init(999,71); //不分频。PWM频率=72000000/1000/72=1Khz 周期为1ms
while(1)
{
TIM_SetCompare1(TIM4,200); //占空比20%
TIM_SetCompare2(TIM4,300); //占空比30%
TIM_SetCompare3(TIM4,400); //占空比40%
TIM_SetCompare4(TIM4,500); //占空比50%
}
}
二、重映射
下面展示主要的time.c、main.c函数的代码
#include "timer.h"
void TIM4_PWM_Init(u16 arr,u16 psc)
{
GPIO_InitTypeDef GPIO_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);//使能定时器4时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD|RCC_APB2Periph_AFIO, ENABLE); //使能GPIO外设和AFIO复用功能模块时钟
GPIO_PinRemapConfig(GPIO_Remap_TIM4, ENABLE); //TIM4重映射
//GPIO配置
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12|GPIO_Pin_13|GPIO_Pin_14|GPIO_Pin_15;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOD, &GPIO_InitStructure);
//初始化TIM4
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(TIM4, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
//配置TIM4的PWM
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
//CH1
TIM_OC1Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC1PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH12
TIM_OC2Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC2PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH13
TIM_OC3Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC3PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
//CH14
TIM_OC4Init(TIM4, &TIM_OCInitStructure); //根据T指定的参数初始化外设TIM3 OC2
TIM_OC4PreloadConfig(TIM4, TIM_OCPreload_Enable); //使能TIM3在CCR2上的预装载寄存器
TIM_Cmd(TIM4, ENABLE); //使能TIM4
}
#include "timer.h"
int main(void)
{
delay_init(); //延时函数初始化
TIM4_PWM_Init(999,71); //不分频。PWM频率=72000000/1000/72=1Khz 周期为1ms
while(1)
{
TIM_SetCompare1(TIM4,200); //占空比20%
TIM_SetCompare2(TIM4,300); //占空比30%
TIM_SetCompare3(TIM4,400); //占空比40%
TIM_SetCompare4(TIM4,500); //占空比50%
}
}