Millis overflow?

Help & Information
1

I’ve got a bit of code that sometimes hangs:

    if(millis()>startMillis+3000){
      gameMode=5;
    }

It doesn’t go past here, but only sometimes. startMillis is set = to millis() by a button press in a previous gameMode.

Is this because millis is overflowing? Is there a elegant way to capture this or should I just use my own counter?

2

You could look at how the Arduboy2 library nextFrame() function uses the millis() timer. It properly handles timer overflows.

Also look at this:
https://www.norwegiancreations.com/2018/10/arduino-tutorial-avoiding-the-overflow-issue-when-using-millis-and-micros/

1 Like
3

I knew it was something simple, I was scratching my head on it. The only reason I posted it was I figure other people have run into it before might be worth talking about. Thanks!

1 Like
4

It would be good to know what datatype you’re using for startMillis. It should be at least unsigned long (uint32_t for AVR).

However, I’m wondering if something millis() does is interfering with the timers the sound libraries are using.

5

well it was an int, so that would explain the behavior more. :rofl: Is there some way to mark two solutions or should that be the correct one?

6

I’m still not entirely sure if overflow actually was the source of the problem, but if it is then @MLXXXp’s comment should be the solution because the linked tutorial tackles the problem of overflow in depth.

7

With great solution button comes great responsibility