This is a simple but very useful example sketch for sensing binary things; like open/closed doors or the state of a wall switch.
The Arduino Pro Mini board has 13 independent digital input pins that can be used to sense the open/closed state of something.
By enabling the internal pull-up resistor (like we've done in this example) you don't need an external pull-up resistor. Just connect the push-button or reed switch between GND and one of the 13 independent digital inputs.
The sketch also takes advantage of the Debounce-library to filter out false triggers.
Wiring Things Up
Start by connecting the radio module.
| Sensor | Arduino | Comment |
|---|---|---|
| Switch | GND | Black |
| Switch | Digital pin 3 | Green |
Example
This example uses the external Bounce2 library found here. Please install it and restart the Arduino IDE before trying to compile.
/**
* The MySensors Arduino library handles the wireless radio link and protocol
* between your home built sensors/actuators and HA controller of choice.
* The sensors forms a self healing radio network with optional repeaters. Each
* repeater and gateway builds a routing tables in EEPROM which keeps track of the
* network topology allowing messages to be routed to nodes.
*
* Created by Henrik Ekblad <[email protected]>
* Copyright (C) 2013-2015 Sensnology AB
* Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
*
* Documentation: http://www.mysensors.org
* Support Forum: http://forum.mysensors.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
*******************************
*
* DESCRIPTION
*
* Simple binary switch example
* Connect button or door/window reed switch between
* digitial I/O pin 3 (BUTTON_PIN below) and GND.
* http://www.mysensors.org/build/binary
*/
// Enable debug prints to serial monitor
#define MY_DEBUG
// Enable and select radio type attached
#define MY_RADIO_RF24
//#define MY_RADIO_RFM69
#include <MySensors.h>
#include <Bounce2.h>
#define CHILD_ID 3
#define BUTTON_PIN 3 // Arduino Digital I/O pin for button/reed switch
Bounce debouncer = Bounce();
int oldValue=-1;
// Change to V_LIGHT if you use S_LIGHT in presentation below
MyMessage msg(CHILD_ID,V_TRIPPED);
void setup()
{
// Setup the button
pinMode(BUTTON_PIN,INPUT);
// Activate internal pull-up
digitalWrite(BUTTON_PIN,HIGH);
// After setting up the button, setup debouncer
debouncer.attach(BUTTON_PIN);
debouncer.interval(5);
}
void presentation() {
// Register binary input sensor to gw (they will be created as child devices)
// You can use S_DOOR, S_MOTION or S_LIGHT here depending on your usage.
// If S_LIGHT is used, remember to update variable type you send in. See "msg" above.
present(CHILD_ID, S_DOOR);
}
// Check if digital input has changed and send in new value
void loop()
{
debouncer.update();
// Get the update value
int value = debouncer.read();
if (value != oldValue) {
// Send in the new value
send(msg.set(value==HIGH ? 1 : 0));
oldValue = value;
}
}
