 
 void loop()
 {
-	// Flush
+	// Flush the serial input buffer
 	Serial.flush();
 	while (Serial.available() > 0) {
 #if DEBUG

	while (n) {
		int a;
		while (n && (a = Serial.available()) > 0) {
			c = Serial.read();
#if DEBUG
			Serial.print(F("Dc = "));
			Serial.print(c);

	}
	snprintf(send_buffer_first, sizeof send_buffer_first, fmt, buffer_size);
	// Choice of threshold
	//threshold = buffer_size * 3 / 4 + 1;
	threshold = buffer_size;
	snprintf(send_buffer, sizeof send_buffer, fmt, threshold);
	//
	int c = -1;
