关于stm32F207输出PWM的问题？

stm32wwxf

stm32F207的TIM1_ETR能输出PWM么？我配置了没有输出怎么回事TIM1_Ch1N有波形

1. GPIO_InitTypeDef GPIO_InitStructure;
   
2.         TIM_TimeBaseInitTypeDef  TIM_TimeBaseStructure;
   
3.         TIM_OCInitTypeDef  TIM_OCInitStructure;
   
4.         TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
   
5. 
   
6.         TIM_DeInit(TIM1);//初始化TIM1寄存器
   
7.         RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE, ENABLE);
   
8.         RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1 , ENABLE);  //使能GPIO外设和AFIO复用功能模块时钟
   
9.        
   
10.         GPIO_PinAFConfig(GPIOE, GPIO_PinSource7, GPIO_AF_TIM1);
    
11.         GPIO_PinAFConfig(GPIOE, GPIO_PinSource8, GPIO_AF_TIM1);//完全重映射 连接 TIM1 引脚到 AF1   
    
12. 
    
13.         /*Configure GPIO pins : PE7 PE8 */
    
14.         GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7|GPIO_Pin_8;//TIM1_ETR,TIM1_CH1N,
    
15.         GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    
16.         GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
    
17.         GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    
18.         GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
    
19.        
    
20.         GPIO_Init(GPIOE, &GPIO_InitStructure);//初始化GPIO
    
21. 
    
22. 
    
23.        //初始化TIM1
    
24.         TIM_TimeBaseStructure.TIM_Period = arr; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值
    
25.         TIM_TimeBaseStructure.TIM_Prescaler =psc; //设置用来作为TIMx时钟频率除数的预分频值
    
26.         TIM_TimeBaseStructure.TIM_ClockDivision = 0; //设置时钟分割:TDTS = Tck_tim
    
27.         TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;  //TIM向上计数模式
    
28.         TIM_TimeBaseStructure.TIM_RepetitionCounter = 0x0;
    
29.         TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure); //根据TIM_TimeBaseInitStruct中指定的参数初始化TIMx的时间基数单位
    
30.        
    
31.         //初始化TIM1 Channel1 PWM模式         
    
32.         TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //选择定时器模式:TIM脉冲宽度调制模式1
    
33.         TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
    
34.         TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
    
35.         TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性:TIM输出比较极性高
    
36.         TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCPolarity_High; //互补端的极性
    
37.         TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
    
38.         TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
    
39.         TIM_OCInitStructure.TIM_Pulse = arr/2;
    
40.         TIM_OC1Init(TIM1, &TIM_OCInitStructure);  //初始化外设TIM1 OC1
    
41.        
    
42. 
    
43.         TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
    
44.   TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
    
45.   TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
    
46.   TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
    
47.   TIM_BDTRInitStructure.TIM_DeadTime = 0;  //这里调整死区大小0-0xff
    
48.   TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
    
49.   TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
    
50.   TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
    
51.   TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
    
52.     //TIM_OC1NPolarityConfig(TIM1, TIM_OCNPolarity_High);
    
53.     //TIM_OC1PolarityConfig(TIM1,TIM_OCPolarity_Low);
    
54.    
    
55.     //TIM_CCPreloadControl(TIM1, ENABLE);
    
56.   TIM_Cmd(TIM1, ENABLE);//使能TIM1
    
57.   TIM_CtrlPWMOutputs(TIM1, ENABLE);//设置PMW主输出        

复制代码

bin133

ETR是输入的

GJJ1999

ETR用于外部时钟输入的，定时器使用外部时钟源，一般是用于脉冲计数的

stm32wwxf

GJJ1999 发表于 2021-12-22 18:26
ETR用于外部时钟输入的，定时器使用外部时钟源，一般是用于脉冲计数的

那只有用它模拟PWM输出了噢。

stm32wwxf

bin133 发表于 2021-12-22 18:32
ETR是输入的

了解了，现在只有用作普通IO模拟PWM输出了