Project36.Reed Switch Module
==============================

Description
------------
The KY-025 Reed Switch Module is a small electrical switch operated by an applied 
magnetic field, commonly used as proximity sensor.
The module has both digital and analog outputs. A trimmer is used to calibrate 
the sensitivity of the sensor.
Compatible with Arduino, Raspberry Pi, ESP32 and other microcontrollers. 
For digital output only use the :doc:`KY-021 mini reed switch <26.reed_switch>`.

Specification
--------------
Operation Voltage	3.3V ~ 5.5V
Board Dimensions	1.5cm x 3.6cm


Connect
--------
.. image:: /img/connect/36_bb.png

Code
-----
.. code-block:: c

    int led = 13; // define the LED pin
    int digitalPin = 2; // KY-028 digital interface
    int analogPin = A0; // KY-028 analog interface
    int digitalVal; // digital readings
    int analogVal; //analog readings

    void setup()
    {
    pinMode(led, OUTPUT);
    pinMode(digitalPin, INPUT);
    //pinMode(analogPin, OUTPUT);
    Serial.begin(9600);
    }

    void loop()
    {
    // Read the digital interface
    digitalVal = digitalRead(digitalPin); 
    if(digitalVal == HIGH) // if temperature threshold reached
    {
        digitalWrite(led, HIGH); // turn ON Arduino's LED
    }
    else
    {
        digitalWrite(led, LOW); // turn OFF Arduino's LED
    }

    // Read the analog interface
    analogVal = analogRead(analogPin); 
    Serial.println(analogVal); // print analog value to serial

    delay(100);
    }

Phenomenon
-----------

.. image:: /img/phenomenon/36.jpg