In my project I invoke a python script via node.js on my Rapberrypi B+ model and what the python script does is that it turns on the BCM GPIO ports as per the python arguments passed through the node.js

$>python my_gpio.py 27 1

where 27 is the pin no and 1 is the on/off state

#my_gpio.py code

import sys
import RPi.GPIO as GPIO

f= open("GPIO","a+")

pin = sys.argv[1]
gpin = int(sys.argv[1])
state = sys.argv[2]

GPIO.setup(gpin, GPIO.OUT)

if state == "1" :
    f.write("\nPIN " +pin + " is on "+ state )
    GPIO.output(gpin, GPIO.HIGH)

    f.write("\nPIN " +pin + " is off "+ state)
    GPIO.output(gpin, GPIO.LOW)


What my objective is that I want to keep my LED HIGH until next event from the node to turn it off or turn it on

  • Should I be worried of not using GPIO.cleanup()? If i use GPIO.cleanup it will turn of the LED right?
  • Will there be any issue if I execute the above code like this,
    $>python my_gpio.py 27 1
    $>python my_gpio.py 27 1
    ie, calling GPIO.output(gpin, GPIO.HIGH) on a GPIO.HIGH
  • What are the risk i should avoid, so that i wont fry my board?

1 Answer 1


I would have no concern at all. My pigpio Python module has no equivalent of the cleanup method.

As far as I am aware the only GPIO libraries which have a cleanup method are RPi.GPIO and RPIO.GPIO (which is based on RPi.GPIO).

If a GPIO is already in the state you command (high when you command high, low when you command low) the command is in effect a no operation. It does no harm (or good).

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