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單片機(jī)型號(hào)：stm32f103rct6 我用定時(shí)器3的pc7口進(jìn)行輸出PWM波形來控制L2898N 但是代碼調(diào)了好幾遍就是不能輸出PWM波形 有沒有大佬給我解答一下，這是為什么？代碼如下：
void PWM_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;//定義結(jié)構(gòu)體
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC | RCC_APB2Periph_AFIO, ENABLE);//使能GPIO外設(shè)和AFIO復(fù)用功能模塊時(shí)鐘
GPIO_PinRemapConfig(GPIO_FullRemap_TIM3, ENABLE); //選擇Timer3全部重映像
//選擇定時(shí)器3的通道2作為PWM的輸出引腳 GPIOC.7
TIM_DeInit(TIM3);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7; //TIM_CH2
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //復(fù)用推挽功能
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);//初始化引腳
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;//定義初始化結(jié)構(gòu)體
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE); //使能定時(shí)器3時(shí)鐘
//初始化TIM3
TIM_TimeBaseStructure.TIM_Period = 9999; //自動(dòng)重裝載寄存器的值
TIM_TimeBaseStructure.TIM_Prescaler =143; //TIMX預(yù)分頻的值
TIM_TimeBaseStructure.TIM_ClockDivision = 0; //時(shí)鐘分割
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //向上計(jì)數(shù)
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure); //根據(jù)以上功能對(duì)定時(shí)器進(jìn)行初始化
TIM_OCInitTypeDef TIM_OCInitStructure;//定義結(jié)構(gòu)體
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;//選擇定時(shí)器模式，TIM脈沖寬度調(diào)制模式2
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;//輸出
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OC2Init(TIM3, &TIM_OCInitStructure);//根據(jù)結(jié)構(gòu)體信息進(jìn)行初始化
TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Enable); //使能定時(shí)器TIM2在CCR2上的預(yù)裝載值
TIM_ARRPreloadConfig(TIM3,ENABLE);
TIM_Cmd(TIM3, ENABLE); //使能定時(shí)器TIM3
}
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