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- 2020-6-19
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/****************************************
* 文件名 :pwm_output.c
* 描述 :
* 实验平台:STM32F103C8T6
*
*
*******************************
**************************/
#include "pwm_output.h"
u32 ArrValue;
u32 PscValue=1;
u32 DeadValue;
float CCR2_Val;
u32 OutFrequency;
/* 配置TIM1复用输出PWM时用到的I/O */
static void TIM1_GPIO_Config(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
/* TIM1 clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
/* GPIOA and GPIOB clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_8;//CH1
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_13;//CH1N
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
/*配置TIM1输出的PWM信号的模式,如周期、极性、占空比 */
void TIM1_Mode_Config(unsigned int arr,unsigned int pcs,unsigned int CCR2_Val ,unsigned char Dead)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM1_BDTRInitStruct;
/* -----------------------------------------------------------------------
TIM1配置:产生2个不同占空比的PWM信号:
TIM1CLK = 72mhz, Prescaler = 0x0, TIM1计数器= 36mhz
TIM3 ARR寄存器= 50000 => TIM1频率= TIM1计数器/(ARR + 1)
TIM3频率= 1440Hz。
TIM1通道1占空比= (TIM1_CCR1/ TIM1_ARR)* 100
TIM1通道2占空比= (TIM1_CCR2/ TIM1_ARR)* 100
----------------------------------------------------------------------- */
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = arr;/*设置了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。它的取值必须在 0x0000 和0xFFFF 之间。*/
TIM_TimeBaseStructure.TIM_Prescaler = pcs;//预分频值取值必须在 0x0000 和 0xFFFF 之间
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;//时钟分割//与死区时间分频有关
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;//向上计数模式
TIM_TimeBaseStructure.TIM_RepetitionCounter=0;//重复寄存器,用于自动更新pwm占空比
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;//PWM2模式
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;//比较互补输出使能
TIM_OCInitStructure.TIM_Pulse = CCR2_Val; //比较值,即占空比
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High; //输出极性
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;//开反向通道//互补输出极性
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;//指定空闲状态下的TIM输出比较的引脚状态。//死区后输出状态
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset; //指定空闲状态下的TIM互补输出比较的引脚状态。//死区后互补端输出状
/****** 配置BDTR寄存器,配置死区时间****************/
/*
定时器时12钟 72M TIM_ClockDivision = TIM_CKD_DIV1时, Tdts = 13.89ns
0 - 1.764us 用算法一
DT: 表示死区持续时间,
Tdts:为系统时钟周期,
Tdtg:表示乘以倍数后死区设置时间步进值
DT = Tdts * Tdtg
1.778us - 3.505us 用算法二
3.556us - 7.000us 用算法三
7.1117us - 14us 用算法四
需要更长时间,使用TIM_ClockDivision分频
*/
TIM1_BDTRInitStruct.TIM_OSSRState = TIM_OSSRState_Disable;//失能OSSR状态
TIM1_BDTRInitStruct.TIM_OSSIState = TIM_OSSIState_Disable;//失能OSSI状态
TIM1_BDTRInitStruct.TIM_LOCKLevel = TIM_LOCKLevel_OFF;//不锁任何 位
TIM1_BDTRInitStruct.TIM_DeadTime = Dead; //死区时间设置 72:1us 128:2us 192:3us// 205:us
TIM1_BDTRInitStruct.TIM_Break = TIM_Break_Disable;//失能 TIM1 刹车输入
TIM1_BDTRInitStruct.TIM_BreakPolarity = TIM_BreakPolarity_High;//TIM1 刹车输入管脚极性高
TIM1_BDTRInitStruct.TIM_AutomaticOutput = TIM_AutomaticOutput_Disable;//自动输出功能失能
TIM_BDTRConfig(TIM1,&TIM1_BDTRInitStruct);
TIM_OC1Init(TIM1, &TIM_OCInitStructure);//根据T指定的参数初始化外设TIM1
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable); //使能TIM1在CCR1上的预装载寄存器
TIM_ARRPreloadConfig(TIM1, ENABLE);//使能或者失能 TIMx 在 ARR 上的预装载寄存器
/* TIM1 enable counter */
TIM_Cmd(TIM1, ENABLE);//使能定时器1
TIM_CtrlPWMOutputs(TIM1, ENABLE); //使能PWM外围输出
}
/*配置和初始化TIM1 */
void TIM1_PWM_Init(void)
{
TIM1_GPIO_Config();
}
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