TimerOne Max Period

Projects Programming
1

I have code snippet below:

#include <TimerOne.h>

void setup(void) {
  Timer1.initialize(5000000);
  Timer1.attachInterrupt(update);
}


void update() {

}

From Arduino Playground - HomePage, it says timer1 max period is 8388.608ms.

What I want is to call update method every 20 seconds, but it didn't work.

Timer1.initialize(5000000);

Every hour, update will take more than 10 seconds w/c is beyond timer1 max period

Any workaround? thanks

2

Every hour, update will take more than 10 seconds w/c is beyond timer1 max period

update() is an interrupt handler. No way in hell it can take 10 seconds.

3

Counter inside of ISR (update() function) should solve it. If counter overflows then set the global flag and do the rest of job in the loop().

4

I mean in update() method, it could take 10seconds let say it will turn few revolutions of a stepper motor.

5

jrgalia:
What I want is to call update method every 20 seconds, but it didn't work.

Definitely don't use Timer1 for this, its completely the wrong approach.

#define DELAY 20000ul

unsigned long last_time = 0ul ;

void loop ()
{
  if (millis () - last_time >= DELAY)
  {
    last_time += DELAY ;
    update () ;
  }
  ....
}

....