最近遇到一個奇怪的問題:

如果用一個程序單獨用定時器內中斷每隔1s點亮LED,此時LED亮度是正常的,單獨的呼吸燈程序LED亮度也正常

后來另外寫了一個程序將上面定時器內部中斷每隔1s點亮LED的功能跟PWM呼吸燈的程序合并在一起后呼吸燈亮度就變的很暗了,但是呼吸燈是能夠正常呼吸的

以上是什么原因導致的?

程序如下:

#include "stm32f10x.h" // Device header
#include "Led.h"
#include "Timer.h"
#include "PWM.h"
#include "Delay.h"
#include "SysTick.h"

uint16_t i;

int main(void)
{
// SysTick_Init(72);
Timer_Init();
LED_Init();
PWM_Init(100,720); //1000Hz
while(1)
{
for(i=0; i<=100; i++)
{
PWM_SetCompare1(i);
PWM_SetCompare2(i);
Delay_ms(10);
}

for(i=0; i<=100; i++)
{
PWM_SetCompare1(100-i);
PWM_SetCompare2(100-i);
Delay_ms(10);
}
}
}

#include "stm32f10x.h" // Device header

void PWM_Init(uint16_t Per, uint16_t Psc)
{
//íaéè2?êy?á11ì?
GPIO_InitTypeDef GPIO_InitStruct;
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
TIM_OCInitTypeDef TIM_OCInitStruct;

//íaéèê±?ó?a??
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOC, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);

//??ó3é?òy??PA6μ?PC6
GPIO_PinRemapConfig(GPIO_FullRemap_TIM3, ENABLE);

//GPIO?á11ì?2?êyéè??
GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStruct.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;
GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOC,&GPIO_InitStruct);

//????ê±?ùμ￥?aμ?ê±?ó?′
TIM_InternalClockConfig(TIM3);

//?¨ê±?÷ê±?ù?á11ì?2?êyéè??
TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInitStruct.TIM_Period = Per-1; //ARR ?¤??×°???μ
TIM_TimeBaseInitStruct.TIM_Prescaler = Psc-1; //PSC ?¤·??μ?μêy
TIM_TimeBaseInitStruct.TIM_RepetitionCounter = 0;
TIM_TimeBaseStructInit(&TIM_TimeBaseInitStruct);

//ê?3?±è???á11ì?2?êyéè??
TIM_OCStructInit(&TIM_OCInitStruct);
TIM_OCInitStruct.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStruct.TIM_OCPolarity = TIM_OCPolarity_Low;
TIM_OCInitStruct.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStruct.TIM_Pulse = 0; //CCR ??êy?÷
TIM_OC1Init(TIM3, &TIM_OCInitStruct);
TIM_OC2Init(TIM3, &TIM_OCInitStruct);

// TIM_ARRPreloadConfig(TIM3, ENABLE);
// TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);

//ê1?ü?¨ê±?÷
TIM_Cmd(TIM3, ENABLE);

}

//éè??CCR,??±?PWM????±è
void PWM_SetCompare1(uint16_t Compare)
{
TIM_SetCompare1(TIM3, Compare);
}

void PWM_SetCompare2(uint16_t Compare)
{
TIM_SetCompare2(TIM3, Compare);
}

//éè???¤·??μ?μ,??±?PWM?μ?ê
void PWM_Prescaler(uint16_t Prescaler)
{
TIM_PrescalerConfig(TIM3, Prescaler, TIM_PSCReloadMode_Immediate);
}

審核編輯 黃宇