Conditionals

/*

Conditionals - If statement

This example demonstrates the use of if() statements.

It reads the state of an analog sensor and turns on an LED

only if the reading goes above a certain threshold level. It prints the

analog value regardless of the level.

The circuit:

Center pin of the moisture sensor goes to analog pin 0.

Side pins of the moisture sensor go to +5V and ground.

- LED connected from digital pin 13 to ground through 220 ohm resistor

- TIP120 Transistor connected to digital Pin 13 to drive pump

- Note: On most Arduino boards, there is already an LED on the board connected

to pin 13, so you don't need any extra components for this example.

created 17 Jan 2009

modified 9 Apr 2012

by Tom Igoe

This example code is in the public domain.

https://www.arduino.cc/en/Tutorial/BuiltInExamples/ifStatementConditional

*/

// These constants won't change:

const int analogPin = A0; // pin that the sensor is attached to

const int ledPin = 13; // pin that the LED is attached to

const int threshold = 400; // an arbitrary threshold level that's in the range of the analog input

void setup() {

// initialize the LED pin as an output:

pinMode(ledPin, OUTPUT);

// initialize serial communications:

Serial.begin(9600);

}

void loop() {

// read the value of the potentiometer:

int analogValue = analogRead(analogPin);

// if the analog value is high enough, turn on the LED:

if (analogValue > threshold) {

digitalWrite(ledPin, HIGH);

} else {

digitalWrite(ledPin, LOW);

}

// print the analog value:

Serial.println(analogValue);

delay(1); // delay in between reads for stability

}