清定时器中断

lqwzjay · 发表于 2011-8-12 17:48:26

void TIM1_UP_IRQHandler(void)
{
extern u16 Am,y,Datavalue;
extern double da_w,y1;
DAC_InitTypeDef            DAC_InitStructure;
static int iii=0;
    if(TIM_GetITStatus(TIM1,TIM_IT_Update)!=RESET)
    {
         TIM_ClearITPendingBit(TIM1, TIM_FLAG_Update); //清中断标志

TIM1->SR&=~(1<<0);//再清除中断标志位 ~~清不掉啊~~ 寄存器的UIF位一直是打勾的~~

   DAC_StructInit(&DAC_InitStructure); //把结构体的成员按初始值填入

   DAC_InitStructure.DAC_Trigger = DAC_Trigger_Software;

   DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;

  // DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bits8_0;

   DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Disable;//DAC_OutputBuffer_Enable;//

   DAC_Init(DAC_Channel_1, &DAC_InitStructure);

DAC_Cmd(DAC_Channel_1, ENABLE); //在通道使能之前PA4,PA5应先配置成模拟输入

DAC_SoftwareTriggerCmd(DAC_Channel_1,ENABLE);

   y1=Am*sin(6.283*iii/100);      //用正弦函数计算
   y=Am+(int)y1;
   if(iii==99)
   iii=0;
   else
   iii=iii+1;

   DAC_SetChannel1Data(DAC_Align_12b_R, y); //把要转换的值送入寄存器
   DAC_DualSoftwareTriggerCmd(ENABLE);       //使能软件触发,更新DAC的值
   Datavalue=DAC_GetDataOutputValue(DAC_Channel_1);
    }

}

定时器1中断函数,仿真的时候,寄存器的UIF位一直都是打勾的,