stm32 pwm 控制电机正反转

TIM2_IRQHandler                   ; TIM2                                            
TIM3_IRQHandler                   ; TIM3                                            
TIM4_IRQHandler                   ; TIM4 
TIM5_IRQHandler                   ; TIM5 
TIM6_DAC_IRQHandler               ; TIM6 and DAC1&2 underrun errors                   
TIM7_IRQHandler                   ; TIM7    
TIM1_BRK_TIM9_IRQHandler          ; TIM1 Break and TIM9                   
TIM1_UP_TIM10_IRQHandler          ; TIM1 Update and TIM10                 
TIM1_TRG_COM_TIM11_IRQHandler     ; TIM1 Trigger and Commutation and TIM11
TIM8_BRK_TIM12_IRQHandler         ; TIM8 Break and TIM12                  
TIM8_UP_TIM13_IRQHandler          ; TIM8 Update and TIM13 
TIM8_TRG_COM_TIM14_IRQHandler     ; TIM8 Trigger and Commutation and TIM14

//TIM3 PWM 初始化 PA6 TIM3CH1 PA7 TIM3 CH2  
//arr 自动重装值
//psc 时钟预分频系数
void TIM3_PWM_Init(u32 arr,u32 psc)
{		 					 
	//io口配置
	
	GPIO_InitTypeDef GPIO_InitStructure;
	TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
	TIM_OCInitTypeDef  TIM_OCInitStructure;
	
	RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3,ENABLE);  	//TIM3 时钟初始化
	RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE); 	//GPIO口初始化
	
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource6,GPIO_AF_TIM3); //GPIO复用为定时器功能
	GPIO_PinAFConfig(GPIOA,GPIO_PinSource7,GPIO_AF_TIM3); 
	
	GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;           //GPIO
	GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;        //复用功能
	GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;	//速度100MHz
	GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;      //推挽复用输出
	GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;        //上拉
	GPIO_Init(GPIOA,&GPIO_InitStructure);              
  
	//定时器配置 
	TIM_TimeBaseStructure.TIM_Prescaler=psc;  //时钟预分频
	TIM_TimeBaseStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
	TIM_TimeBaseStructure.TIM_Period=arr;   //自动重装载值
	TIM_TimeBaseStructure.TIM_ClockDivision=TIM_CKD_DIV1; 
	
	TIM_TimeBaseInit(TIM3,&TIM_TimeBaseStructure);//TIM3
	
	//定时器pwm输出配置
	TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; // pwm 脉宽调制1模式 即计数器值小于比较值时高电平大于时低电平
 	TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
	TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出比较极性高
	TIM_OCInitStructure.TIM_OutputNState = TIM_OutputState_Disable; //N??????
	TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset ; // 必须加，否则只有一路输出
	TIM_OC1Init(TIM3, &TIM_OCInitStructure);  //tim3 ch1 初始化
	
	
	TIM_OC2Init(TIM3, &TIM_OCInitStructure);  //tim3 ch2 初始化

	TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能tim3 ch1 预装载寄存器
	TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable);  //使能tim3 ch2 预装载寄存器
 
                TIM_ARRPreloadConfig(TIM3,ENABLE);//ARPE使能
	
	TIM_Cmd(TIM3, ENABLE);  //使能TIM3
 
										  
}  

void Prun(u32 c1,u32 c2)
{
 TIM_SetCompare1(TIM3,c1); // TIM3 CH1 比较，大于c1反转
 TIM_SetCompare2(TIM3,c2); 
}

int main(void)
{ 
	u16 PWM_HZ = 1000;	// pwm运行频率 1kHz 1ms
	u16 PSC = 84 ; //时钟预分频系数
	u32 CLK_CNT = 84000000;
	u32 TOTAL_CLK_HZ = CLK_CNT/PSC;	// 1s 的计数次数 84M/84 = 1M hz
	u32 TOTAL_CNT = TOTAL_CLK_HZ/PWM_HZ; //定时器的最大计数值，决定了pwm的频率
	u8 dir=1;
	u32 ms_delay = 500; // 10ms/doublerate
	u32 cnt_cmp = 80; //高电平持续8%
	NVIC_PriorityGroupConfig(NVIC_PriorityGroup_2); //中断分组初始化
	delay_init(168);  //延时初始化
	// uart_init(115200);//串口波特率初始化
 	TIM3_PWM_Init(TOTAL_CNT-1,PSC-1);	//pwm初始化
   	while(1) //主循环
	{
 		delay_ms(ms_delay);	//每0.5s反转一次
		if(dir) 
		{
			dir = 0;
			Prun(cnt_cmp,0);//dir==1 正转
		}
		else 
		{
			dir = 1;
			Prun(0,cnt_cmp);	//dir==0 反转
		}
	}
}