定时器1捕获比较触发AD转换

Blueyas

   /* ADC1 regular channel 12 configuration ************************************/
   xADC_InitStructure.ADC_ScanConvMode = DISABLE;
   xADC_InitStructure.ADC_ContinuousConvMode = DISABLE;
   xADC_InitStructure.ADC_ExternalTrigConvEdge = ADC_ExternalTrigConvEdge_RisingFalling; //上升沿和下降沿触发检测
   xADC_InitStructure.ADC_ExternalTrigConv = ADC_ExternalTrigConv_T1_CC2;   //选择定时器1的捕获比较2作为转换外部触发
   xADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
   xADC_InitStructure.ADC_NbrOfConversion = 1;
   ADC_Init(ADC1, &xADC_InitStructure);


看到一个程序，定时器触发AD转换，脉冲接的是PA8脚，查看手册PA8是TIM1_CH1，但为什么是ADC_ExternalTrigConv_T1_CC2，不是ADC_ExternalTrigConv_T1_CC1呢？