中断知识

使用一个中断读取编码器的值,
#define PinA 2  //中断0
long count = 0; //计数值
long num = 0;
void setup() 
{
Serial.begin(9600); //窗口初始化
pinMode(PinA,INPUT); //D2脚为输入
pinMode(3,INPUT); //D3脚为输入
attachInterrupt(0, blinkA, RISING);  //注册中断0调用函数blinkA
}
void loop()
{
while (num != count)
  {
    num = count;
    Serial.println(num);
  }
}
void blinkA()
{
  if(digitalRead(3)==1)
       { count ++;}
       if(digitalRead(3)==0)
       {count--;}
}