Directly connecting to Optical Pulse Counter with RPi?

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I’ve recently found this script and put it to use. I’ve also been on a mission to reduce CPU use and found the script uses 100% CPU. The problem was the way the while loop was working.

The while loop at the end is the main difference.

import RPi.GPIO as GPIO
import time
import socket

# a "pulse" is 1 unit of measurement use emonHub scales and unit to define
# eg if 100 pulses is 1m3, ie 0.01m3 each then emonHub should use scale = 0.01 and unit = m3
# Therefore "pulse_id" becomes an accumulating "total used" and should follow the meter reading

nodeid = 18
valueid = 1
bounce = 1
interval = 5
lastsend = 0
host = "localhost" #emonbase1"
port = 50012
pulse_pin1 = 21
pulse_pin2 = 15

pulse_id = {1:0,2:0}

def eventHandler1(channel):
    processpulse(1,GPIO.input(channel))
def eventHandler2(channel):
    processpulse(2,GPIO.input(channel))


#    print("event")

def processpulse(channel,status):
    global pulse_id
    global frame
    global lastsend
    if status: #GPIO.input(channel):
        pulse_id[channel] += 1
        print("Channel "+ str(channel) + "  on : " + str(pulse_id[channel]))
    else:
        print("Channel "+ str(channel) + " off : " + str(pulse_id[channel]))

    t = time.time()
    f = ' '.join((str(t), str(nodeid), str(pulse_id[1]), str(pulse_id[2])))
    if t > (lastsend + interval):
        lastsend = t
        print f
        send(f)


def send(f):
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.connect((host, port))
    f = f + '\r\n'
    s.send(f)
    s.close()


if rpi:
    GPIO.setmode(GPIO.BOARD)
    GPIO.setup(pulse_pin1, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
    GPIO.add_event_detect(pulse_pin1, GPIO.BOTH, callback=eventHandler1, bouncetime=bounce)
    GPIO.setup(pulse_pin2, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
    GPIO.add_event_detect(pulse_pin2, GPIO.BOTH, callback=eventHandler2, bouncetime=bounce)


try: # CTRL+C to break - requires graceful exit
    while True:
        time.sleep(5) # the value doesn't matter.
except KeyboardInterrupt:
    GPIO.cleanup() # clean up GPIO on CTRL+C exit
    exit()

GPIO.cleanup() # just in case

time.sleep() could be a millisecond, one second, 5000 seconds, makes no difference, as long as the program is running the interrupts will happen and callbacks are initiated immediately.
I hope that helps.

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