这个是STM32的PWM输出形式,STM32的TIM1模块是增强型的定时器模块,天然生成便是为电机操控而生,能够产生3组6路PWM,一起每组2路PWM为互补,并能够带有死区,能够用来驱动H桥。
下面的代码,是使用TIM1模块的1、2通道产生总共4路PWM的代码比如,相似代码也能够参阅ST的固件库中相应example
C言语:TIM1模块产生PWM,带死区
//Step1.敞开TIM和相应端口时钟
//发动GPIO
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | \
RCC_APB2Periph_GPIOC | RCC_APB2Periph_GPIOD,\
ENABLE);
//发动AFIO
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
//发动TIM1
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
//Step2. GPIO做相应设置,为AF输出
//PA.8/9口设置为TIM1的OC1输出口
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8 | GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
//PB.13/14口设置为TIM1_CH1N和TIM1_CH2N输出口
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13 | GPIO_Pin_14;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//Step3. TIM模块初始化
void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_BaseInitStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
//TIM1根本计数器设置(设置PWM频率)
//频率=TIM1_CLK/(ARR+1)
TIM_BaseInitStructure.TIM_Period = 1000-1;
TIM_BaseInitStructure.TIM_Prescaler = 72-1;
TIM_BaseInitStructure.TIM_ClockDivision = 0;
TIM_BaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_BaseInitStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM1, &TIM_BaseInitStructure);
//启用ARR的影子寄存器(直到产生更新事情才更改设置)
TIM_ARRPreloadConfig(TIM1, ENABLE);
//TIM1_OC1模块设置(设置1通道占空比)
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_Pulse = 120;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
//启用CCR1寄存器的影子寄存器(直到产生更新事情才更改设置)
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
//TIM2_OC2模块设置(设置2通道占空比)
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_Pulse = 680;
TIM_OC2Init(TIM1, &TIM_OCInitStructure);
//启用CCR2寄存器的影子寄存器(直到产生更新事情才更改设置)
TIM_OC2PreloadConfig(TIM1, TIM_OCPreload_Enable);
//死区设置
TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 0x90; //这儿调整死区巨细0-0xff
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
//TIM1敞开
TIM_Cmd(TIM1, ENABLE);
//TIM1_OC通道输出PWM(一定要加)
TIM_CtrlPWMOutputs(TIM1, ENABLE);
}
其实,PWM模块还能够有许多把戏能够玩,比如在反常时(如CPU时钟有问题),能够紧迫封闭输出,避免产生电路焚毁等严重事故