STM32L151 PWM 求助

bruce.kuo 提问时间：2015-11-10 10:33 /

你好!
以下是我使用STM32L151開發PWM輸出的設定 , 但都沒有波形輸出 , 請問各位先進我的CODE哪裡有問題
謝謝

TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_OCInitTypeDef TIM_OCInitStruct;
GPIO_InitTypeDef GPIO_InitStructure;

RCC_HSICmd(ENABLE);

while (RCC_GetFlagStatus(RCC_FLAG_HSIRDY) == RESET) {}
RCC_SYSCLKConfig(RCC_SYSCLKSource_HSI);

// Enable clock for GPIOA
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA,ENABLE);
// Enable clock for TIM4
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4,ENABLE);

GPIO_StructInit(&GPIO_InitStructure);
GPIO_PinAFConfig(GPIOA,GPIO_PinSource1,GPIO_AF_TIM4);
GPIO_InitStructure.GPIO_Pin =  GPIO_Pin_1;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_40MHz;
GPIO_Init(GPIOA,&GPIO_InitStructure);

TIM_TimeBaseStructInit(&TIM_TimeBaseInitStruct);
TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV4;
TIM_TimeBaseInitStruct.TIM_Period = 1000 - 1;
TIM_TimeBaseInitStruct.TIM_Prescaler = 240 - 1;
TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM4,&TIM_TimeBaseInitStruct);

TIM_OCStructInit(&TIM_OCInitStruct);
TIM_OCInitStruct.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStruct.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStruct.TIM_Pulse = 0;

TIM_OC1Init(TIM4,&TIM_OCInitStruct);
//TIM_OC2Init(TIM4,&TIM_OCInitStruct);

TIM_Cmd(TIM4,ENABLE);