#include "PWM.h"
extern u16 zhankong;
void PWM_init(u16 a,u16 b)
{
GPIO_InitTypeDef GPIO_InitStruct;
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_OCInitTypeDef TIM_OCInitStructure;
// TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO|RCC_APB2Periph_GPIOB,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1,DISABLE);
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP ;
GPIO_PinRemapConfig(GPIO_PartialRemap_TIM1,ENABLE);
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_8;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA,&GPIO_InitStruct);
TIM_TimeBaseInitStruct.TIM_Period = 0;//自動裝載ARR的值
TIM_TimeBaseInitStruct.TIM_Prescaler =300;
TIM_TimeBaseInitStruct.TIM_ClockDivision = 0;
TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInitStruct.TIM_RepetitionCounter =0;
TIM_TimeBaseInit(TIM1,&TIM_TimeBaseInitStruct);
TIM_OCInitStructure.TIM_Pulse = a;//比較CCR的值,決定脈沖寬度,決定占空比
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1; //選擇定時器模式:TIM脈沖寬度調制模式
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;//比較輸出使能TIM_
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
//TIM_OCInitStructure.TIM_OutputState = TIM_OutputNState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low; //輸出極性:TIM輸出比較極性高
TIM_OC1Init(TIM1, &TIM_OCInitStructure); //根據T指定的參數初始化外設TIM3 OC2
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable); //使能TIM3在CCR2上的預裝載寄存器
TIM_CtrlPWMOutputs(TIM1, ENABLE);
TIM_Cmd(TIM1,ENABLE);
}
void pwm(void)
{TIM_SetAutoreload(TIM1, 0X3000);//設置預裝載寄存器
TIM_SetCompare1( TIM1,zhankong);//設置占空
}
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