Can't turn on LEDs through terminal with PWM

Question

I wrote a crappy Python script that should turn on LEDs connected to the GPIO interface.

import RPi.GPIO as GPIO
import time, sys, json

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
gpioPorts = [4, 9, 22]

for i in range(len(gpioPorts)):
    GPIO.setup(gpioPorts[i], GPIO.OUT)

pwm = {}
for i in range(1, len(sys.argv), 2):
    if sys.argv[i] == 4 or 9 or 22:
        if int(sys.argv[i + 1]) >= 5 and int(sys.argv[i + 1]) <= 100: 
            pwm["{0}".format(int(sys.argv[i]))] =  GPIO.PWM(int(sys.argv[i]), 120)
            pwm[sys.argv[i]].start(int(sys.argv[i + 1]))
        elif int(sys.argv[i + 1]) == 0:
            GPIO.output(int(sys.argv[i]), False)

def getStatus(gpioPorts):
    status = {}
    for i in range(len(gpioPorts)):
        if GPIO.input(gpioPorts[i]) == 0:
            status[gpioPorts[i]] = 0
        else:
            status[gpioPorts[i]] = 1
    return status

print(json.dumps(getStatus(gpioPorts)))

When I enter

%Run script.py 4 100 9 20 22 50

in Thonny IDE, it should turn on LED on the GPIO Port 4 with 100% brightness, LED 9 with 20% brightness and LED 22 with 50% brightness. I can change the brightness and everything works fine, but when I enter:

sudo python script.py 4 100 9 20 22 50

in LXTerminal the LEDs flicker and then go out directly. Why does my code work in Thonny but not in the terminal?

EDIT:

import RPi.GPIO as GPIO
import time, sys, json

GPIO.setmode(GPIO.BCM)
GPIO.setwarnings(False)
gpioPorts = [4, 9, 22]

for i in range(len(gpioPorts)):
    GPIO.setup(gpioPorts[i], GPIO.OUT)

for i in range(1, len(sys.argv), 2):
    if sys.argv[i] == 4 or 9 or 22:
        if int(sys.argv[i + 1]) == 1: 
            GPIO.output(int(sys.argv[i]), True)
        elif int(sys.argv[i + 1]) == 0:
            GPIO.output(int(sys.argv[i]), False)

def getStatus(gpioPorts):
    status = {}
    for i in range(len(gpioPorts)):
        if GPIO.input(gpioPorts[i]) == 0:
            status[gpioPorts[i]] = 0
        else:
            status[gpioPorts[i]] = 1
    return status

print(json.dumps(getStatus(gpioPorts)))

I don't need

time.sleep(60)

when I'm not using PWM. I can run the same Code in Thonny and in the terminal. Why do I need "time.sleep ()" in the above code but not in the lower code?

Answer 1

You have not told the script to continue running. From the terminal it will run the script commands then stop.

Presumably in the Thonny IDE the script does not shut down properly.

Add something like a time.sleep(60) after the print statement to let the script run for 60 seconds.

Answer 2

I just found out, that it is not possible to run a PWM python script "forever": https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=124281