problem with interrupts firing at the wrong time

Using Arduino Programming Questions
1

hi
I have a problem that I cant quite figure out whats causing it.

I'm using an Arduino Mega

I need to detect 3 momentary push buttons

im my code I called them

GoButton (pin 21)
travelLimit (pin 19)
Rest (pin 20)

Ive set up an interrupt for each button

    attachInterrupt(digitalPinToInterrupt(19),endOfTravelReached,CHANGE);   
    attachInterrupt(digitalPinToInterrupt(20),reset,CHANGE);  
    attachInterrupt(digitalPinToInterrupt(21),go_Button,CHANGE);

And Im using the internal pull up resistors

    pinMode(19,INPUT_PULLUP);
    pinMode(20,INPUT_PULLUP); 
    pinMode(21,INPUT_PULLUP);

For some reason, occasionally when I press the GoButton, the Reset gets triggered instead.

I've attached the entire Sketch too.

any help , ideas etc .. is appreciated

keypad2.ino (10.6 KB)

2

What kind of wiring (e.g. network cable, ...)? What is the distance between Arduino and switches?

3

the distance is about 100 mm / 4 inches , why?

4

sammypati:
the distance is about 100 mm / 4 inches , why?

Because you could be suffering cross-talk.

5

Why do you need interrupts to detect push button activation? Non-blocking polling from loop() would probably work fine.

6

GFVAlvo
Your right , interrupts may not needed in its current state, but the sketch isn't finished yet.
Once I add the other features I need, I think I will need interrupts, but Ill know better once its all done.
If I need to I can easily remove them and place the checks inline in the Loop section.

Either way I cant see that making a difference to the issue I'm having. (unless I'm missing something?)

AWOL
The problem could be cross talk, but I'm not sure how to get around that.

Any Ideas ?