STM32 红外发射Timer1 ch1 PWM输出

2019-07-21 07:55发布

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1楼-- · 2019-07-21 13:47

上面的代码是当时测试用的，下面的做了些改进

void Timer1_PWM_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
    TIM_TimeBaseInitTypeDef TIM_BaseInitStructure;
    TIM_OCInitTypeDef TIM_OCInitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA|RCC_APB2Periph_AFIO,ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
GPIO_InitStructure.GPIO_Pin=GPIO_Pin_8;
GPIO_InitStructure.GPIO_Mode=GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed=GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
    //TIM1基本计数器设置（设置PWM频率）
    //频率=TIM1_CLK/(ARR+1)
    TIM_BaseInitStructure.TIM_Period = 1894; //不分频。PWM频率=72000/1894=380Khz
    TIM_BaseInitStructure.TIM_Prescaler = 0;
    TIM_BaseInitStructure.TIM_ClockDivision = 0;
    TIM_BaseInitStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_BaseInitStructure.TIM_RepetitionCounter = 0;
    TIM_TimeBaseInit(TIM1, &TIM_BaseInitStructure);
    //启用ARR的影子寄存器（直到产生更新事件才更改设置）
    TIM_ARRPreloadConfig(TIM1, ENABLE);
//TIM1_OC1模块设置（设置1通道占空比）
    TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
    TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
    TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
    TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
    TIM_OC1Init(TIM1, &TIM_OCInitStructure);
    //启用CCR1寄存器的影子寄存器（直到产生更新事件才更改设置）
    TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Enable);
    TIM_Cmd(TIM1, ENABLE); //TIM1开启
    //TIM1_OC通道输出PWM（一定要加）
    TIM_CtrlPWMOutputs(TIM1, ENABLE);
}

void IR_Send(void)
{
//9ms
TIM_Cmd(TIM1, ENABLE);
Delay_nMS(9);
//4.5ms
TIM_Cmd(TIM1, DISABLE);
Delay_nMS(4);
Delay_nUS(500);
IR_Send_Byte(0x00); //用户码
IR_Send_Byte(0xFF); //用户反码
IR_Send_Byte(0x00); //数据码
IR_Send_Byte(0xFF); //数据反码
//下面增加是为了避免在发送最后一位时出现错码
TIM_Cmd(TIM1, ENABLE);
Delay_nUS(565);
TIM_Cmd(TIM1, DISABLE);
Delay_nUS(565);
}

void IR_Send_Byte(u8 getdata)
{
u8 senddata,i;
senddata=getdata;
for(i=0;i<8;i++)
{
if(senddata&0x01)
{
//1
TIM_Cmd(TIM1, ENABLE);
Delay_nUS(565);
TIM_Cmd(TIM1, DISABLE);
Delay_nUS(565);
Delay_nUS(565);
Delay_nUS(565);
}
else
{
//0
TIM_Cmd(TIM1, ENABLE);
Delay_nUS(565);
TIM_Cmd(TIM1, DISABLE);
Delay_nUS(565);
}
senddata=senddata>>1;
}
}