为什么把PB5改为PB4后pwm就没了，示波器看不到了

wlchad · 发表于 2015-10-2 18:42:52

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); //?????¨?±?÷3?±??
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO, ENABLE); //????GPIO???è??AFIO???????????é?±??

GPIO_PinRemapConfig(GPIO_PartialRemap_TIM3, ENABLE); //Timer3??·??????? TIM3_CH2->

B5

//?è??????????????????????,????TIM3 CH2??PWM?????¨?? GPIOB.5
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4; //TIM_CH2
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //???????ì????
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);//??????GPIO

//??????TIM3
TIM_TimeBaseStructure.TIM_Period = arr; //?è???????????ü??????×°????????×?????×°???????÷????????
TIM_TimeBaseStructure.TIM_Prescaler =psc; //?è??????×÷??TIMx?±?????????????¤·?????
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //?è???±??·???:TDTS = Tck_tim
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM?ò??????????
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //?ù??TIM_TimeBaseInitStruct?????¨????????????TIMx???±???ù??????

//??????TIM3 Channel2 PWM????
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //?????¨?±?÷????:TIM?????í???÷??????2
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //±???????????
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //????????:TIM????±?????????
TIM_OC1Init(TIM3, &TIM_OCInitStructure); //?ù??T???¨???????????????èTIM3 OC2

TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable); //????TIM3??CCR2?????¤×°???????÷

TIM_Cmd(TIM3, ENABLE); //????TIM3

}