You can use the SwitchManager library to handle many switch related events in your sketches.
The library provides: switch de-bouncing, timing and state change information.
The SwitchManager.h file should be placed in your libraries folder, i.e.
C:\Users\YouName\Documents\Arduino\libraries\SwitchManager\SwitchManager.h
You may download the library at:
http://gammon.com.au/Arduino/SwitchManager.zip
/*SwitchManager skeleton
LarryD
This is sketch is to introduce new people to the SwitchManager library written by Nick Gammon
The library handles switch de-bouncing and provides timing and state change information in your sketch.
The SwitchManager.h file should be placed in your libraries folder, i.e.
C:\Users\YouName\Documents\Arduino\libraries\SwitchManager\SwitchManager.h
You can download the library at:
http://gammon.com.au/Arduino/SwitchManager.zip Thank you Nick!
In this example we have 2 normally open (N.O.) switches connected to the Arduino - increment and decrement.
The increment switch will also be used as a "Reset" switch if pressed for more than two seconds.
The two switches are connected between GND (0 volts) and an Arduino input pin.
The library enables pull-up resistors for your switch inputs.
Pushing a switch makes its pin LOW. Releasing a switch makes its pin HIGH.
The SwitchManager library provides 10ms de-bounce for switches.
i.e. enum { debounceTime = 10, noSwitch = -1 };
If you need more time, edit the SwitchManager.h file
i.e. enum { debounceTime = 50, noSwitch = -1 }; //here it is changed to 50ms
*/
#include <SwitchManager.h>
//object instantiations
SwitchManager myIncSwitch;
SwitchManager myDecSwitch;
unsigned long currentMillis;
unsigned long heartBeatMillis;
unsigned long heartFlashRate = 500UL; // time the led will change state
unsigned long incShortPress = 500UL; // 1/2 second
unsigned long incLongPress = 2000UL;// 2 seconds
unsigned long decShortPress = 500UL; // 1/2 second
const byte heartBeatLED = 13;
const byte incSwitch = 4; //increment switch is on Arduino pin 4
const byte decSwitch = 5; //decrement switch is on Arduino pin 5
int myCounter;
//======================================================================
void setup()
{
Serial.begin(9600);
//gives a visual indication if the sketch is blocking
pinMode(heartBeatLED, OUTPUT);
myIncSwitch.begin (incSwitch, handleSwitchPresses);
myDecSwitch.begin (decSwitch, handleSwitchPresses);
//the handleSwitchPresses() function is called when a switch changes state
} // E N D O F s e t u p ( )
//======================================================================
void loop()
{
//leave this line of code at the top of loop()
currentMillis = millis();
//***************************
//some code to see if the sketch is blocking
if (CheckTime(heartBeatMillis, heartFlashRate, true))
{
//toggle the heartBeatLED
digitalWrite(heartBeatLED,!digitalRead(heartBeatLED));
}
//***************************
//check to see what's happening with the switches
//"Do not use delay()s" in your sketch as it will make switch changes unresponsive
//Use BlinkWithoutDelay (BWD) techniques instead.
myIncSwitch.check ();
myDecSwitch.check ();
//***************************
//put other non-blocking stuff here
} // E N D O F l o o p ( )
//======================================================================
// F U N C T I O N S
//======================================================================
// C h e c k T i m e ( )
//**********************************************************************
//Delay time expired function
//Parameters:
//lastMillis = time we started
//wait = delay in ms
//restart = do we start again
boolean CheckTime(unsigned long & lastMillis, unsigned long wait, boolean restart)
{
//has time expired for this task?
if (currentMillis - lastMillis >= wait)
{
//should this start again?
if(restart)
{
//yes, get ready for the next iteration
lastMillis += wait;
}
return true;
}
return false;
} // E N D o f C h e c k T i m e ( )
// h a n d l e S w i t c h P r e s s e s( )
//**********************************************************************
void handleSwitchPresses(const byte newState, const unsigned long interval, const byte whichPin)
{
// You get here "ONLY" if there has been a change in a switches state.
// When a switch has changed state, SwitchManager passes this function 3 arguments:
// "newState" this will be HIGH or LOW. This is the state the switch is in now.
// "interval" the number of milliseconds the switch stayed in the previous state
// "whichPin" is the switch pin that we are examining
switch (whichPin)
{
//***************************
//are we dealing with this switch?
case incSwitch:
//has this switch gone from LOW to HIGH (gone from pressed to not pressed)
//this happens with normally open switches wired as mentioned at the top of this sketch
if (newState == HIGH)
{
//was this a short press followed by a switch release
if(interval <= incShortPress)
{
Serial.print("My counter value is = ");
myCounter++;
if(myCounter > 1000)
{
//limit the counter to a maximum of 1000
myCounter = 1000;
}
Serial.println(myCounter);
}
//was this a long press followed by a switch release
else if(interval >= incLongPress)
//we could also have an upper limit
//if incLongMillis was 2000UL; we could then have a window between 2-3 seconds
//else if(interval >= incLongMillis && interval <= incLongMillis + 1000UL)
{
//this could be used to change states in a StateMachine
//in this example however, we will just reset myCounter
myCounter = 0;
Serial.print("My counter value is = ");
Serial.println(myCounter);
}
}
else //the switch must have gone from HIGH to LOW
{
//if the switch is a normally closed (N.C.) and opens on a press this section would be used
}
break; //End of case incSwitch
//***************************
//are we dealing with this switch?
case decSwitch:
//has this switch gone from LOW to HIGH (gone from pressed to not pressed)
//this happens with normally open switches wired as mentioned at the top of this sketch
if (newState == HIGH)
{
//was this a short press followed by a switch release
if(interval <= decShortPress)
{
Serial.print("My counter value is = ");
myCounter--;
if(myCounter < 0)
{
//don't go below zero
myCounter = 0;
}
Serial.println(myCounter);
}
}
else //the switch must have gone from HIGH to LOW
{
//if the switch is a normally closed (N.C.) and opens on a press this section would be used
}
break; //End of case decSwitch
//***************************
//Put default stuff here
//default:
//break; //END of default
} //End switch (whichPin)
} // E n d o f h a n d l e S w i t c h P r e s s e s ( )
//======================================================================
// E N D O F C O D E
//======================================================================
