新手求助！编译有误

jerryhere

新手求助！
刚学，如下第一个程序，提示编译有误。。。
问题在哪里呢？
求助各位高手了。谢谢！！！

void setup()
{
  // put your setup code here, to run once:
for(pinNum=2; pinNum<=9; pinNum++)
{
  pinMode(pinNum,OUTPUT);
}
}
void loop()
{
  // put your main code here, to run repeatedly:
digitalWrite(9,HIGH);
digitalWrite(8,LOW);
digitalWrite(7,LOW);
digitalWrite(6,LOW);
digitalWrite(5,LOW);
digitalWrite(4,LOW);
digitalWrite(3,LOW);
digitalWrite(2,LOW);

delay(3000);
}

328522073

for(pinNum=2; pinNum<=9; pinNum++)
{
  pinMode(pinNum,OUTPUT);
}
改成
for(byte pinNum=2; pinNum<=9; pinNum++)
{
  pinMode(pinNum,OUTPUT);
}