Make the button differentiate between 2x and 1x press

Using Arduino Programming Questions
1

How do you differentiate if the button is pressed once, light 1 is on and pressed twice, light 2 is on, then if you press it once, light 1 is off and pressed twice, light 2 is off, similar to a smartphone when you tap it twice, the screen is on?

2

Hello bimosora

You might use the millis() function for time measurement.

3

you have a finite state machine with 4 states:

  • if the button is pressed once, light 1 is on --> 1 0
  • and pressed twice, light 2 is on, --> 1 1
  • then if you press it once, light 1 is off --> 0 1
  • and pressed twice, light 2 is off, --> 0 0

so make a counter which counts from 0 to 3
every time you press the button, increase the counter and handle your outputs according to the state.

1 Like
4

Is it like this?

unsigned long currentMillis = 0;
unsigned long previousMillis = 0;

if(digitalRead(10))
{
   currentMillis = millis();
   if(currentMillis - previousMillis >= 200 && !digitalRead(10))
   {
      //oneclick

      previousMillis = currentMillis;
      bool firstClick = true;

   }else if(currentMillis - previousMillis >= 200 && digitalRead(10) && firstclick)
   {

      //DoubleClick
      
      previousMillis = currentMillis;
      firstClick = false;

   }else if(currentMillis - previousMillis >= 2000 && digitalRead(10))
   {
      //long click (hold for 2000 ms or 2s)
      previousMillis = currentMillis;
   }

   firstClick = false;
}
5

Iā€™d suggest you check the code for one of the numerous button library handling double click such as OneButton

Matthias has taken the time to write some notes about his implementation and he explains the state machine he is using

OneButtonFSM2
OneButtonFSM21125Ɨ692 66.9 KB

2 Likes
6

I won't use the library because later I will try single tap and double tap code using RFID

7

the point was studying the code, not using the library if you don't want to. That will give you an understanding about Finite state machines (Here is a small introduction to the topic: Yet another Finite State Machine introduction)

8

thats something different.

It seems you want something like:

single click --> toggle Output 1
double click --> toogle Output 2

so the question is, what system behaviour you really want...

9

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