定时器的频率配置

1、STM32定时器的频率配置STM32 定时器产生不同频率的PWM      平时记性实在太差，调试完的程序，过两天又忘了，往往需要一阵子才能想起来，有时以前的资料找不到了，更是恼火，不得不重复到网上搜索。刚刚调试成功了一个类型的程序，立刻记下来，呵呵，不要又忘记了。     STM32产生PWM是非常的方便的，要需要简单的设置定时器，即刻产生！当然，简单的设置对于新手来产，也是麻烦的，主要包括：（1）使能定时器时钟：RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, E

2、NABLE);（2）定义相应的GPIO： /* PA2,3,4,5,6输出->Key_Up,Key_Down,Key_Left,Key_Right,Key_Ctrl */GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; /下拉接地，检测输入的高电平GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; /50M时钟速度GPIO_Init

3、(GPIOA, &GPIO_InitStructure);/* PA7用于发出PWM波,即无线数据传送 */GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; /50M时钟速度GPIO_Init(GPIOA, &GPIO_InitStructure);（3）如果是产生PWM（频率不变，占空比可变），记得打开PWM控制，在TIM_Con

4、figuration()中。TIM_Cmd(TIM3,ENABLE);/* TIM1 Main Output Enable */TIM_CtrlPWMOutputs(TIM1,ENABLE);利用定时器产生不同频率的PWM    有时候，需要产生不同频率的PWM，这个时候，设置与产生相同PWM的程序，有关键的不一样。（一） 设置的原理     利用改变定时器输出比较通道的捕获值，当输出通道捕获值产生中断时，在中断中将捕获值改变，这时， 输出的I/O会产生一个电平翻转，利用这种办法，实现不同频率的PWM输出。（二）关键设置在定

5、时器设置中：TIM_OC2PreloadConfig(TIM3, TIM_OCPreload_Disable);在中断函数中： if (TIM_GetITStatus(TIM3, TIM_IT_CC2) != RESET)          TIM_ClearITPendingBit(TIM3, TIM_IT_CC2);   capture = TIM_GetCapture2(TIM3);    TIM_SetCompare2(TIM3, capture + Key

6、_Value);一个定时器四个通道，分别产生不同频率（这个例子网上也有）vu16 CCR1_Val = 32768;vu16 CCR2_Val = 16384;vu16 CCR3_Val = 8192;vu16 CCR4_Val = 4096; void TIM_Configuration(void)TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;TIM_OCInitTypeDef TIM_OCInitStructure;/* TIM2 clock enable */RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2

7、, ENABLE);/* -TIM2 Configuration: Output Compare Toggle Mode:TIM2CLK = 36 MHz, Prescaler = 0x2, TIM2 counter clock = 12 MHz CC1 update rate = TIM2 counter clock / CCR1_Val = 366.2 HzCC2 update rate = TIM2 counter clock / CCR2_Val = 732.4 Hz CC3 update rate = TIM2 counter clock / CCR3_Val = 1464.8 Hz

8、 CC4 update rate = TIM2 counter clock / CCR4_Val = 2929.6 Hz - */* Time base configuration */TIM_TimeBaseStructure.TIM_Period = 65535;          TIM_TimeBaseStructure.TIM_Prescaler = 2;       TIM_TimeBaseStructure.TIM_ClockDiv

9、ision = 0;    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);/* Channel 1 Configuration in PWM mode */TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;      /PWM模式2TIM_OCInitStructure.TIM_OutputState

10、 = TIM_OutputState_Enable; /正向通道有效TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Disable;/反向通道无效TIM_OCInitStructure.TIM_Pulse = CCR1_Val;         /占空时间TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;    /输出极性TIM_OCInitStructure.TIM_OCNPol

11、arity = TIM_OCNPolarity_High;     /互补端的极性 TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset; TIM_OC1Init(TIM2,&TIM_OCInitStructure);        /通道1TIM_OC1PreloadConfig(TIM2, TIM_OC

12、Preload_Disable);TIM_OCInitStructure.TIM_Pulse = CCR2_Val;         /占空时间TIM_OC2Init(TIM2,&TIM_OCInitStructure);        /通道2TIM_OC2PreloadConfig(TIM2, TIM_OCPreload_Disable);TIM_OCInitStructure.TIM_Pulse = CCR3_Val;   

13、0;     /占空时间TIM_OC3Init(TIM2,&TIM_OCInitStructure);        /通道3TIM_OC3PreloadConfig(TIM2, TIM_OCPreload_Disable);TIM_OCInitStructure.TIM_Pulse = CCR4_Val;         /占空时间TIM_OC4Init(TIM2,&TIM_OCInitStructure);

14、        /通道4TIM_OC4PreloadConfig(TIM2, TIM_OCPreload_Disable);/* TIM2 counter enable */TIM_Cmd(TIM2,ENABLE);/* TIM2 Main Output Enable */TIM_CtrlPWMOutputs(TIM2,ENABLE);   /* TIM IT enable */TIM_ITConfig(TIM2, TIM_IT_CC1 | TIM_IT_CC2 | TIM_IT_CC3 | TIM_IT_CC4,

15、 ENABLE);void GPIO_Configuration(void)GPIO_InitTypeDef GPIO_InitStructure;/*允许总线CLOCK,在使用GPIO之前必须允许相应端的时钟.从STM32的设计角度上说,没被允许的端将不接入时钟,也就不会耗能,这是STM32节能的一种技巧,*/RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph

16、_GPIOC, ENABLE);RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOD, ENABLE);/* PA2,3,4,5,6,7输出->LED1,LED2,LED3,LED4,LED5,LED6 */GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2|GPIO_Pin_3|GPIO_Pin_4|GPIO_Pin_5|GPIO_Pin_6|GPIO_Pin_7;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD; /开漏输出GPIO_InitStructure.GPIO_Sp

17、eed = GPIO_Speed_50MHz; /50M时钟速度GPIO_Init(GPIOA, &GPIO_InitStructure);/* PB0,1输出->LED7,LED8*/GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_OD; /开漏输出GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; /50M时钟速度GPIO_Init(GPIOB, &GPIO_InitStruc

18、ture);/* PA0,1->KEY_LEFT,KEY_RIGHT*/GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;   /上拉输入GPIO_Init(GPIOA, &GPIO_InitStructure);/* PC13->KEY_UP*/GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_I

19、PU;   /上拉输入GPIO_Init(GPIOC, &GPIO_InitStructure);/* PB5->KEY_DOWN*/GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;   /上拉输入GPIO_Init(GPIOB, &GPIO_InitStructure);/* GPIOA Configuration:TIM2 Channel1, 2, 3 and 4 in Output */GPIO_Init

20、Structure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3;GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;GPIO_Init(GPIOA, &GPIO_InitStructure);void NVIC_Configuration(void)NVIC_InitTypeDef NVIC_InitStructure;/* Configure one bit for p

21、reemption priority */NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);NVIC_InitStructure.NVIC_IRQChannel=TIM2_IRQn;NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0;NVIC_InitStructure.NVIC_IRQChannelSubPriority=1;NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;NVIC_Init(&NVIC_InitStructure);u16

22、capture = 0;extern vu16 CCR1_Val;extern vu16 CCR2_Val;extern vu16 CCR3_Val;extern vu16 CCR4_Val;void TIM2_IRQHandler(void)/* TIM2_CH1 toggling with frequency = 183.1 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET)    TIM_ClearITPendingBit(TIM2, TIM_IT_CC1 );capture = TIM_GetCaptu

23、re1(TIM2);TIM_SetCompare1(TIM2, capture + CCR1_Val );/* TIM2_CH2 toggling with frequency = 366.2 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC2) != RESET)     TIM_ClearITPendingBit(TIM2, TIM_IT_CC2);capture = TIM_GetCapture2(TIM2);    TIM_SetCompare2(TIM2, capture + CCR

24、2_Val); /* TIM2_CH3 toggling with frequency = 732.4 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC3) != RESET)    TIM_ClearITPendingBit(TIM2, TIM_IT_CC3);capture = TIM_GetCapture3(TIM2);    TIM_SetCompare3(TIM2, capture + CCR3_Val);/* TIM2_CH4 toggling with frequency = 1464.8

25、 Hz */if (TIM_GetITStatus(TIM2, TIM_IT_CC4) != RESET)     TIM_ClearITPendingBit(TIM2, TIM_IT_CC4);capture = TIM_GetCapture4(TIM2);    TIM_SetCompare4(TIM2, capture + CCR4_Val);一个定时器一个通道，产生不同频率其它的设置都一样，就是在主函数中修改一个参数，然后在定时器中断中，根据这个参数，改变频率。#include "stm32libstm32f10x.

26、h"#include "hal.h"volatile u16 Key_Value=1000;   /用于保存按键相应的PWM波占空比值int main(void)ChipHalInit();ChipOutHalInit();while(1)     if( (!Get_Key_Up)&(!Get_Key_Down)&(!Get_Key_Left)&(!Get_Key_Right)&(!Get_Key_Ctrl) )      

27、; Key_Value=12000;      else        if(Get_Key_Up)     /按键前进按下 ,对应1kHz         Key_Value=6000;         else if(Get_Key_Down)   /按键后退按下 ,对应2kHz  &

28、#160;         Key_Value=3000;          Delay_Ms(20);      /10ms延时    if(Get_Key_Left)    /按键左转按下,对应3kHz         Key_Value=2000;  &

29、#160;      else if(Get_Key_Right) /按键右转按下,对应4kHz           Key_Value=1500;             Delay_Ms(20);      /10ms延时    if(Get_Key_Ctrl)  

30、  /按键控制按下,对应5kHz          Key_Value=1200;        Delay_Ms(20);      /10ms延时    extern volatile u16 Key_Value;u16 capture=0;void TIM3_IRQHandler(void)/* TIM2_CH2 toggling with frequency = 366.2 Hz

31、 */if (TIM_GetITStatus(TIM3, TIM_IT_CC2) != RESET)     TIM_ClearITPendingBit(TIM3, TIM_IT_CC2);capture = TIM_GetCapture2(TIM3);    TIM_SetCompare2(TIM3, capture + Key_Value); void TIM3_Configuration(void)TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;TIM_OCInitTypeD

32、ef TIM_OCInitStructure;/* TIM2 clock enable */RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);/*TIM1时钟配置*/TIM_TimeBaseStructure.TIM_Prescaler = 5;       /预分频(时钟分频)72M/6=12MTIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;   /向上计数TIM_TimeBaseStructure.TIM_Period = 65535;        /装载值选择最大TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;TIM_TimeBaseStruc