+ Demonstrates analog input by reading an analog sensor on analog pin 0 and
+ turning on and off a light emitting diode(LED) connected to digital pin 13.
+ The amount of time the LED will be on and off depends on
+ the value obtained by analogRead().
+ * Potentiometer attached to analog input 0
+ * center pin of the potentiometer to the analog pin
+ * one side pin (either one) to ground
+ * the other side pin to +5V
+ * LED anode (long leg) attached to digital output 13
+ * LED cathode (short leg) attached to ground
+ * Note: because most Arduinos have a built-in LED attached
+ to pin 13 on the board, the LED is optional.
+ Created by David Cuartielles
+ This example code is in the public domain.
+int sensorPin = A0; // select the input pin for the potentiometer
+int ledPin = 2; // select the pin for the LED
+int sensorValue = 0; // variable to store the value coming from the sensor
+int sensorValueMax = 1023;
+ // declare the ledPin as an OUTPUT:
+ pinMode(ledPin, OUTPUT);
+ // read the value from the sensor:
+ sensorValue = analogRead(sensorPin);
+ halfPeriod = map(sensorValue,sensorValueMin,sensorValueMax,halfPeriodMin,halfPeriodMax);
+ digitalWrite(ledPin, HIGH);
+ // stop the program for <sensorValue> milliseconds:
+ // turn the ledPin off:
+ digitalWrite(ledPin, LOW);
+ // stop the program for for <sensorValue> milliseconds: