int buzzer=8;// select digital IO pin for the buzzer
void setup()
{
pinMode(buzzer,OUTPUT);// set digital IO pin pattern, OUTPUT to be output
}
void loop()
{ 
unsigned char i,j;//define variable
while(1)
{ 
for(i=0;i<80;i++)// output a frequency sound
{ 
  digitalWrite(buzzer,HIGH);// sound
  delay(1);//delay1ms
  digitalWrite(buzzer,LOW);//not sound
  delay(1);//ms delay
}
for(i=0;i<100;i++)// output a frequency sound
{ 
  digitalWrite(buzzer,HIGH);// sound
  digitalWrite(buzzer,LOW);//not sound
  delay(2);//2ms delay
}
}
}