Timer A的疑问
下面是设置不同的流水灯速度,对程序有一些费解,就是每个速度选择的代码为什么总是先加一条这个 TACTL &=~ (ID0 + ID1);,下面是全部代码:switch(speed)
{
case 0:
TACTL &=~ (ID0 + ID1);
TACTL |= ID_3;
break;
case 1:
TACTL &=~ (ID0 + ID1);
TACTL |= ID_2;
break;
case 2:
TACTL &=~ (ID0 + ID1);
TACTL |= ID_1;
break;
case 3:
TACTL &=~ (ID0 + ID1);
TACTL |= ID_0;
break;
default:
break;
}
if(flag != 3) speed++;
if(speed == 4) speed = 0;
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