STM32输入捕获TIM2四通道

相比于一通道，原子的例程里因为清了计数时间，所以要对程序进行修改。

记录上升沿后的计数，然后记录下降沿的计数。相减后计算高电平时间，对于定时器中断间隔的边界要分开处理。

这里因为我的接收机时间是1ms~2ms，而中断时间设置为20ms。所以根本不需要考虑时间延迟超过计时器时间。

下面是我的代码

//arr:自动重装值 psc:时钟预分频数
//定时器溢出时间计算：Tout=((arr+1)*(psc+1))/Ft   us
//Ft = 定时器工作频率，单位Mhz
//TIM2在APB1上，为HCLK/2   36Mhz
void TIM2_CAP_Init(u16 arr, u16 psc)
{
    GPIO_InitTypeDef GPIO_InitStruct;
    TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStruct;
    TIM_ICInitTypeDef TIM_ICInitStruct;
    NVIC_InitTypeDef NVIC_InitStruct;
    //开启TIM2和GPIO时钟
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
    //PA0初始化
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_IPD;            //下拉输入
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_0|GPIO_Pin_1|GPIO_Pin_2|GPIO_Pin_3;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    //TIM2定时器初始化
    TIM_TimeBaseInitStruct.TIM_Period = arr;
    TIM_TimeBaseInitStruct.TIM_Prescaler = psc;
    TIM_TimeBaseInitStruct.TIM_ClockDivision = TIM_CKD_DIV1;
    TIM_TimeBaseInitStruct.TIM_CounterMode = TIM_CounterMode_Up;        //向上计数
    TIM_TimeBaseInit(TIM2, &TIM_TimeBaseInitStruct);

    //TIM2_CH1输入捕获初始化
    TIM_ICInitStruct.TIM_Channel = TIM_Channel_1;
    TIM_ICInitStruct.TIM_ICFilter = 0x00;                            //不滤波
    TIM_ICInitStruct.TIM_ICPolarity = TIM_ICPolarity_Rising;        //上升沿捕获
    TIM_ICInitStruct.TIM_ICPrescaler = TIM_ICPSC_DIV1;                //输入器不分频
    TIM_ICInitStruct.TIM_ICSelection = TIM_ICSelection_DirectTI;    //映射到IC1
    TIM_ICInit(TIM2, &TIM_ICInitStruct);

    TIM_ICInitStruct.TIM_Channel = TIM_Channel_2;
    TIM_ICInitStruct.TIM_ICFilter = 0x00;                            //不滤波
    TIM_ICInitStruct.TIM_ICPolarity = TIM_ICPolarity_Rising;        //上升沿捕获
    TIM_ICInitStruct.TIM_ICPrescaler = TIM_ICPSC_DIV1;                //输入器不分频
    TIM_ICInitStruct.TIM_ICSelection = TIM_ICSelection_DirectTI;    //映射到IC2
    TIM_ICInit(TIM2, &TIM_ICInitStruct);

    TIM_ICInitStruct.TIM_Channel = TIM_Channel_3;
    TIM_ICInitStruct.TIM_ICFilter = 0x00;                            //不滤波
    TIM_ICInitStruct.TIM_ICPolarity = TIM_ICPolarity_Rising;        //上升沿捕获
    TIM_ICInitStruct.TIM_ICPrescaler = TIM_ICPSC_DIV1;                //输入器不分频
    TIM_ICInitStruct.TIM_ICSelection = TIM_ICSelection_DirectTI;    //映射到IC3
    TIM_ICInit(TIM2, &TIM_ICInitStruct);

    TIM_ICInitStruct.TIM_Channel = TIM_Channel_4;
    TIM_ICInitStruct.TIM_ICFilter = 0x00;                            //不滤波
    TIM_ICInitStruct.TIM_ICPolarity = TIM_ICPolarity_Rising;        //上升沿捕获
    TIM_ICInitStruct.TIM_ICPrescaler = TIM_ICPSC_DIV1;                //输入器不分频
    TIM_ICInitStruct.TIM_ICSelection = TIM_ICSelection_DirectTI;    //映射到IC4
    TIM_ICInit(TIM2, &TIM_ICInitStruct);

    //中断分组初始化
    NVIC_InitStruct.NVIC_IRQChannel = TIM2_IRQn;
    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = ;
    NVIC_InitStruct.NVIC_IRQChannelSubPriority = ;
    NVIC_Init(&NVIC_InitStruct);    

    TIM_ITConfig(TIM2, TIM_IT_CC1|TIM_IT_CC2|TIM_IT_CC3|TIM_IT_CC4, ENABLE);            //更新中断和CC1IE捕获中断

    TIM_Cmd(TIM2, ENABLE);
    printf("Init TIM2 CAP success\n");
}

然后是中断处理函数

//捕获状态
//[7]:0,没有成功捕获；1,成功捕获到一次
//[6]:0,还没捕获到低电平;1,已经捕获到低电平了.
//[5:0]:捕获低电平后溢出第次数
u8 CAPTURE_STA_TIM2CH[] = {};
u16 CAPTURE_VAL_TIM2CH[];
u16 CAPTURE_UP_TIM2CH[], CAPTURE_DOWN_TIM2CH[];
void TIM2_IRQHandler(void)
{
//    if(TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET) {
//        if((CAPTURE_STA_TIM2CH[1]&0x80) == 0) {            //还未捕获成功
//            if(CAPTURE_STA_TIM2CH[1]&0x40) {            //已经捕获到高电平了
//                if((CAPTURE_STA_TIM2CH[1]&0x3F)==0x3F) {            //高电平太长了
//                    CAPTURE_STA_TIM2CH[1] |= 0x80;                //标记成功捕获了一次
//                    CAPTURE_VAL_TIM2CH[1] = 0xFFFF;
//                } else
//                    CAPTURE_VAL_TIM2CH[1]++;
//            }
//        }
//        TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
//    }

    if((CAPTURE_STA_TIM2CH[]&0x80) == ) {                    //还未捕获成功
        if(TIM_GetITStatus(TIM2, TIM_IT_CC1) != RESET) {    //捕获1发生捕获事件
            if(CAPTURE_STA_TIM2CH[]&0x40) {                    //捕获到一个下降沿
                CAPTURE_STA_TIM2CH[] |= 0x80;                    //标记成功捕获到一次高电平脉宽
                CAPTURE_DOWN_TIM2CH[] = TIM_GetCapture1(TIM2);
                if(CAPTURE_DOWN_TIM2CH[] >= CAPTURE_UP_TIM2CH[])
                    CAPTURE_VAL_TIM2CH[] = CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                else
                    CAPTURE_VAL_TIM2CH[] = 0xffff + CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                TIM_OC1PolarityConfig(TIM2, TIM_ICPolarity_Rising);    //CC1P=0 设置为上升沿捕获
            } else {                                        //还未开始，第一次捕获上升沿
                CAPTURE_STA_TIM2CH[] = ;                    //清空
                CAPTURE_VAL_TIM2CH[] = ;
                CAPTURE_UP_TIM2CH[] = TIM_GetCapture1(TIM2);
                CAPTURE_STA_TIM2CH[] |= 0x40;                //标记捕获到了上升沿
                TIM_OC1PolarityConfig(TIM2, TIM_ICPolarity_Falling);    //CC1P=1 设置为下降沿捕获
            }
            TIM_ClearFlag(TIM2, TIM_FLAG_CC1);                                //清除状态标志
        }
    } 

    if((CAPTURE_STA_TIM2CH[]&0x80) == ) {                    //还未捕获成功
        if(TIM_GetITStatus(TIM2, TIM_IT_CC2) != RESET) {            //捕获2发生捕获事件
            if(CAPTURE_STA_TIM2CH[]&0x40) {                        //捕获到一个下降沿
                CAPTURE_STA_TIM2CH[] |= 0x80;                        //标记成功捕获到一次高电平脉宽
                CAPTURE_DOWN_TIM2CH[] = TIM_GetCapture2(TIM2);        //获取捕获2计数
                if(CAPTURE_DOWN_TIM2CH[] >= CAPTURE_UP_TIM2CH[])
                    CAPTURE_VAL_TIM2CH[] = CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                else
                    CAPTURE_VAL_TIM2CH[] = 0xffff + CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                TIM_OC2PolarityConfig(TIM2, TIM_ICPolarity_Rising);    //CC1P=0 设置为上升沿捕获
            } else {                                                //还未开始，第一次捕获上升沿
                CAPTURE_STA_TIM2CH[] = ;                            //清空
                CAPTURE_VAL_TIM2CH[] = ;
                CAPTURE_UP_TIM2CH[] = TIM_GetCapture2(TIM2);
                CAPTURE_STA_TIM2CH[] |= 0x40;                //标记捕获到了上升沿
                TIM_OC2PolarityConfig(TIM2, TIM_ICPolarity_Falling);    //CC1P=1 设置为下降沿捕获
            }
            TIM_ClearFlag(TIM2, TIM_FLAG_CC2);                                //清除状态标志
        }
    }

    if((CAPTURE_STA_TIM2CH[]&0x80) == ) {                    //还未捕获成功
        if(TIM_GetITStatus(TIM2, TIM_IT_CC3) != RESET) {            //捕获2发生捕获事件
            if(CAPTURE_STA_TIM2CH[]&0x40) {                        //捕获到一个下降沿
                CAPTURE_STA_TIM2CH[] |= 0x80;                        //标记成功捕获到一次高电平脉宽
                CAPTURE_DOWN_TIM2CH[] = TIM_GetCapture3(TIM2);        //获取捕获2计数
                if(CAPTURE_DOWN_TIM2CH[] >= CAPTURE_UP_TIM2CH[])
                    CAPTURE_VAL_TIM2CH[] = CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                else
                    CAPTURE_VAL_TIM2CH[] = 0xffff + CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                TIM_OC3PolarityConfig(TIM2, TIM_ICPolarity_Rising);    //CC1P=0 设置为上升沿捕获
            } else {                                                //还未开始，第一次捕获上升沿
                CAPTURE_STA_TIM2CH[] = ;                            //清空
                CAPTURE_VAL_TIM2CH[] = ;
                CAPTURE_UP_TIM2CH[] = TIM_GetCapture3(TIM2);
                CAPTURE_STA_TIM2CH[] |= 0x40;                //标记捕获到了上升沿
                TIM_OC3PolarityConfig(TIM2, TIM_ICPolarity_Falling);    //CC1P=1 设置为下降沿捕获
            }
            TIM_ClearFlag(TIM2, TIM_FLAG_CC3);                                //清除状态标志
        }
    }
    if((CAPTURE_STA_TIM2CH[]&0x80) == ) {                    //还未捕获成功
        if(TIM_GetITStatus(TIM2, TIM_IT_CC4) != RESET) {            //捕获2发生捕获事件
            if(CAPTURE_STA_TIM2CH[]&0x40) {                        //捕获到一个下降沿
                CAPTURE_STA_TIM2CH[] |= 0x80;                        //标记成功捕获到一次高电平脉宽
                CAPTURE_DOWN_TIM2CH[] = TIM_GetCapture4(TIM2);        //获取捕获2计数
                if(CAPTURE_DOWN_TIM2CH[] >= CAPTURE_UP_TIM2CH[])
                    CAPTURE_VAL_TIM2CH[] = CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                else
                    CAPTURE_VAL_TIM2CH[] = 0xffff + CAPTURE_DOWN_TIM2CH[] - CAPTURE_UP_TIM2CH[];
                TIM_OC4PolarityConfig(TIM2, TIM_ICPolarity_Rising);    //CC1P=0 设置为上升沿捕获
            } else {                                                //还未开始，第一次捕获上升沿
                CAPTURE_STA_TIM2CH[] = ;                            //清空
                CAPTURE_VAL_TIM2CH[] = ;
                CAPTURE_UP_TIM2CH[] = TIM_GetCapture4(TIM2);
                CAPTURE_STA_TIM2CH[] |= 0x40;                //标记捕获到了上升沿
                TIM_OC4PolarityConfig(TIM2, TIM_ICPolarity_Falling);    //CC1P=1 设置为下降沿捕获
            }
            TIM_ClearFlag(TIM2, TIM_FLAG_CC4);                                //清除状态标志
        }
    }

    //处理帧数据
    if(CAPTURE_STA_TIM2CH[]&0x80) {                                //成功捕获到了一次上升沿                                            //溢出时间总和
        myControl.remoteControl[] = CAPTURE_VAL_TIM2CH[];                            //得到总的高电平时间
//        printf("TIM2 CH1:%d\t", temp[0]);
        CAPTURE_STA_TIM2CH[] = ;
    }
    if(CAPTURE_STA_TIM2CH[]&0x80) {                                //成功捕获到了一次上升沿                                            //溢出时间总和
        myControl.remoteControl[] = CAPTURE_VAL_TIM2CH[];                            //得到总的高电平时间
//        printf("TIM2 CH2:%d\t", temp[1]);
        CAPTURE_STA_TIM2CH[] = ;
    }
    if(CAPTURE_STA_TIM2CH[]&0x80) {                                //成功捕获到了一次上升沿                                        //溢出时间总和
        myControl.remoteControl[] = CAPTURE_VAL_TIM2CH[];                            //得到总的高电平时间
//        printf("TIM2 CH3:%d\t", temp[2]);
        CAPTURE_STA_TIM2CH[] = ;
    }
    if(CAPTURE_STA_TIM2CH[]&0x80) {                                //成功捕获到了一次上升沿                                            //溢出时间总和
        myControl.remoteControl[] = CAPTURE_VAL_TIM2CH[];                            //得到总的高电平时间
//        printf("TIM2 CH4:%d\t", temp[3]);
        CAPTURE_STA_TIM2CH[] = ;
    }
}

这些printf函数会极大的占用MCU资源，所以不在中断中处理。