Sensor Workshop at ITP

/* Analog Bandpass Filter
 * Jeff Gray - 2008
 * ------------------ 
 * Checks average, and only sends events if the new 
 * data is within a certain gate of the average
 */

int average[100];
byte counter = 0;

// amount on either side of average where values will be sent
int gate = 50;

void setup() {
  Serial.begin(19200);
}

void loop() {
  // read the value from the sensor
  int inAn = analogRead(0);

  // set in rolling buffer
  average[counter] =  inAn;

  // average by buffer
  byte c;
  int total = 0;
  for(c = 0;c<100;c++){
    total += average[c];
  }
  int averaged = total / 100;
  // increment position in rolling buffer
  counter = (counter + 1) % 100;

  // set gate for valid data
  if(inAn <= (averaged + gate) && inAn >= (averaged - gate) ){
    Serial.println(inAn);
  }
}