Arduino click, double click and hold button - arduino

Question

I am trying to implement three different functions for one button in an Arduino project. Click, double click and hold.
I have to use interrupts and let the system sleep as much as possible, because the final product will have to run on a coin cell for a few months.
#include <Ports.h>
#include <RF12.h>
#include <avr/sleep.h>
#include <PinChangeInt.h>
#include <VirtualWire.h>
ISR(WDT_vect) { Sleepy::watchdogEvent(); }
char *controller;
const int buttonPin = 3;
bool stateSingle = false;
bool stateDouble = false;
bool stateLong = false;
void setup() {
pinMode(13, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
pinMode(5, OUTPUT);
// vw_set_ptt_inverted(true);
// vw_set_tx_pin(12);
// vw_setup(4000);
//
Serial.begin(9600);
PCintPort::attachInterrupt(buttonPin, wakeUp, HIGH);
}
void wakeUp() {
}
void loop() {
cli();
int i = 0;
while (digitalRead(buttonPin) == HIGH) { // Wait until button is LOW, or has been high for more than 600ms
Sleepy::loseSomeTime(50);
if (i > 12)
break;
i++;
}
if (digitalRead(buttonPin) == HIGH)
longTapAction();
else {
i = 0;
while (digitalRead(buttonPin) == LOW) { // Wait for possible double press
Sleepy::loseSomeTime(50);
if (i > 8)
break;
i++;
}
if (digitalRead(buttonPin) == HIGH) {
doubleTapAction();
while (digitalRead(buttonPin) == HIGH)
Sleepy::loseSomeTime(50);
} else
singleTapAction();
}
}
void singleTapAction() {
stateSingle = !stateSingle;
digitalWrite(5, stateSingle ? HIGH : LOW);
sei();
Sleepy::powerDown();
}
void doubleTapAction() {
stateDouble = !stateDouble;
digitalWrite(6, stateDouble ? HIGH : LOW);
sei();
Sleepy::powerDown();
}
void longTapAction() {
stateLong = !stateLong;
digitalWrite(7, stateLong ? HIGH : LOW);
sei();
Sleepy::powerDown();
}
The problem is that this is not always correctly working.
Because I'm using interrupts, millis() inside void loop() is not reliable, for some reason.
For any double click, and for any hold action, the single click function also gets called. I suspect this is due to multiple interrupts firing, but I have no way to test this. Also, sometimes, the double click seems to need only one click. Is my thinking wrong, did I forget something?

Answer 1

If you are seeing singleTapAction and doubleTapAction triggering too often, the problem could be that your method doesn't really debounce the button inputs, meaning you may read spurious noise on any click as a single press or double press. E.G your first while loop will exit almost immediately if there is a noisy input, which makes the following behavior difficult to predict.
https://www.arduino.cc/en/Tutorial/Debounce
If you have a look at the linked example on the arduino site - a possible solution is to record the period of time an input has been present and ignore any inputs of less than a certain period. Modifying your code to do this could stop the spurious calls.