setSpeed Methode stepper.h

Other Hardware Motors, Mechanics, Power and CNC
1

Hi, i'm french programmer but today i'm not finding answer to my problem on french topics !
So... maybe with my poor english i can explain you the situation ? I'll do my better !

I've two bipolars motors (ref 28BYJ-48), and I'm asking myself the question : what's that strange calcul to setSpeed (library stepper.h) ?

/*Sets the speed in revs per minute*/
void Stepper::setSpeed(long P_whatSpeed) {
    this->step_delay = 60L * 1000L / this->number_of_steps / P_whatSpeed; 
}

(with the 28BYJ-48 number_of_steps=64)

step_delay is an unsigned long, but the result is an "float type" !

I don't understand the meaning of this calculation ! :o What's "60*1000" ? Why don't just asked delay ?

2

I haven't used the Stepper library but from a quick look at the Reference section it seems that you tell it how many steps per revolution there are when you create the stepper instance and then setSpeed takes a number representing RPM.

I presume then, that 60 * 1000 converts RPM into millisecs between steps.

...R

3 
                      milliseconds/minute 
milliseconds/step = -------------------------
                      rev/minute x steps/rev