SequentMicrosystems_API/scripts/speed_reader.py

from src.variables.service import get_variable, set_variable
from gpiozero import Button
import datetime

pulses_per_rotation = 1
reader = Button(4, pull_up=False, bounce_time=0.0005)
set_variable("speed_reader_last_impulse_time", datetime.datetime.now(), False)


def event():
    actual = datetime.datetime.now()
    last = get_variable("speed_reader_last_impulse_time")
    difference = (actual - last).total_seconds()
    set_variable("speed_reader_last_impulse_time", actual, False)

    rpm = (60 / difference) / pulses_per_rotation    
    
    set_variable("actual_rpm", round(rpm, 1), False)




reader.when_pressed = event
reader.when_activated