回复第 2 楼 于2014-09-28 11:37:57发表: 参考以下代码： void Timer_Init(s16 freq) { TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; TIM_OCInitTypeDef TIM_OCInitStructure; GPIO_InitTypeDef GPIO_InitStructure; RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE); GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF; GPIO_InitStructure.GPIO_OType = GPIO_OType_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL; GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0; GPIO_Init(GPIOA, &GPIO_InitStructure); GPIO_PinAFConfig(GPIOA, GPIO_PinSource0, GPIO_AF_1); RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE); /* ----------------------------------------------------------------------- TIM3 Configuration: generate 4 PWM signals with 4 different duty cycles: TIM3CLK = 72 MHz, Prescaler = 0x71, TIM3 counter clock = 1 MHz TIM3 ARR Register = 999 => TIM3 Frequency = TIM3 counter clock/(ARR + 1) so ... TIM3 Frequency = 72MHz / (Prescaler + 1) / (ARR + 1) sooo ... (Prescaler + 1) = 72000000 / (ARR + 1) / Freq TIM3 Frequency = 36 KHz. TIM3 Channel1 duty cycle = (TIM3_CCR1/ TIM3_ARR)* 100 = 50% ----------------------------------------------------------------------- */ /* Time base configuration */ TIM_TimeBaseStructure.TIM_Period = 7200-1; TIM_TimeBaseStructure.TIM_Prescaler = 10000/freq-1; TIM_TimeBaseStructure.TIM_ClockDivision = 0; TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure); /* PWM1 Mode configuration: Channel1 */ TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; TIM_OCInitStructure.TIM_Pulse = TIM_TimeBaseStructure.TIM_Period >> 1; //占空比=1/2 TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; TIM_OC1Init(TIM2, &TIM_OCInitStructure); TIM_OC1PreloadConfig(TIM2, TIM_OCPreload_Enable); TIM_ARRPreloadConfig(TIM2, ENABLE); TIM_Cmd(TIM2, ENABLE); } 有寄存器版本的吗
