I’m attempting to make a a vu meter. when I have the mic hooked up to my arduino and read the values off the serial i get appropriate values.but then when I have it turn on on off my row of LEDs the value my mic is returning will only jump between high and low even in a silent room. for reference the mic returns a signal of about 500 in a quite room and the max will be about 900. but when it jumps between its high and low it gives values of 850 and 100.
int ledPins[]={2,3,4,5,6,7,8,9};
void setup(){
for(int i=0;i<8;i++){
pinMode(ledPins[i],OUTPUT);
}
Serial.begin(9600);
}
void loop(){
int sensorReading = analogRead(A0);
delay (10);
int lon=;
Serial.println(sensorReading);
Serial.println(lon);
Serial.print('\n');
switch (lon){
case 7:
for(int t=0;t<8;t++){digitalWrite(ledPins[t],HIGH);}
break;
case 6:
for(int t=0;t<7;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>6;r--){digitalWrite(ledPins[r],LOW);}
break;
case 5:
for(int t=0;t<6;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>5;r--){digitalWrite(ledPins[r],LOW);}
break;
case 4:
for(int t=0;t<5;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>4;r--){digitalWrite(ledPins[r],LOW); }
break;
case 3:
for(int t=0;t<4;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>3;r--){digitalWrite(ledPins[r],LOW);}
break;
case 2:
for(int t=0;t<3;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>2;r--){digitalWrite(ledPins[r],LOW);}
break;
case 1:
for(int t=0;t<2;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>1;r--){digitalWrite(ledPins[r],LOW);}
break;
case 0:
for(int t=0;t<1;t++){digitalWrite(ledPins[t],HIGH);}
for(int r=7;r>0;r--){digitalWrite(ledPins[r],LOW);}
break;
default:
for(int i=0;i<8;i++){digitalWrite(ledPins[i],LOW);}
break;
}
delay(100);
}