Timer function

Device Code
1

Hi All,
For my idea I need to call my function 10…100 times per second to make some calculation.
To do this I’m tried to use imp.wakeup and I got stack overflow error: ERROR: stack overflow, cannot resize stack while in a metamethod

Here the code:
`function timer() {
imp.wakeup(0.1, timer());
}

timer();`

Do we have any limitation of imp.wakeup usage?
Could someone point me to what I’m doing wrong?

Do we have any other ways to call function periodically?

2

The problem here is that you need to remove the brackets in the imp wakeup, like this:

imp.wakeup(0.1, timer);

…otherwise, it’s calling the timer function when evaluating the expression from within timer and recursing until it runs out of memory.

3

Thanks Hugo! This helps.

I’m trying to add parameter to timer function and got the same error:

function timer(cycles) { cycles--; if (cycles) imp.wakeup(0.01, timer(cycles)); server.log("timer"); } timer(100);

So, as I understand, there no way to use function with parameters as callback for imp.wakeup.

4

The function called at wake-up time can’t have parameters, no. But that function can call other functions, which do:
function timer(cycles) { cycles--; if (cycles) imp.wakeup(1, function() { timer(cycles) } ); server.log("timer "+cycles); } timer(10);

Peter

5

This hack works.
Thanks.

6

This would be a good one for the WIKI