RPi4 GPIO using in LibreELEC

Da Flex

Just been to the local shop to get the switch.

So after some research managed to get it sorted..

Led,Start,Restart and Shutdown all in one..

short press is restart..long press is shutdown..press from off will switch on..

Now gonna test it for a few days...happy to share script if anyone wanna test..

Well although power button works as intended..unfortunately it doesn't work if system is for some reason frozen..so it might still need a dirty power shutdown once in a while..

Led On - Start - Quick Press Restart - Long Press Shutdown

#!/usr/bin/python
# shutdown/reboot(/power on) Raspberry Pi with pushbutton
import sys
sys.path.append('/storage/.kodi/addons/virtual.rpi-tools/lib')
import RPi.GPIO as GPIO
from subprocess import call
from datetime import datetime
import time
# pushbutton connected to this GPIO pin, using gpio 3 (pin 5) also has the benefit of
# waking / powering up Raspberry Pi when button is pressed
shutdownPin = 3
led = 13
# if button pressed for at least this long then shut down. if less then reboot.
shutdownMinSeconds = 3

# button debounce time in seconds
debounceSeconds = 0.01

GPIO.setmode(GPIO.BCM)
GPIO.setup(shutdownPin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(led, GPIO.OUT)
# Switch LED on.
# LED will switch off automatically at shutdown by using normal GPIO state.
GPIO.output(led, True)

buttonPressedTime = None

def buttonStateChanged(pin):
    global buttonPressedTime

    if not (GPIO.input(pin)):
        # button is down
        if buttonPressedTime is None:
            buttonPressedTime = datetime.now()
    else:
        # button is up
        if buttonPressedTime is not None:
            elapsed = (datetime.now() - buttonPressedTime).total_seconds()
            buttonPressedTime = None
            if elapsed >= shutdownMinSeconds:
                # button pressed for more than specified time, shutdown
                call(['shutdown', '-h', 'now'], shell=False)
            elif elapsed >= debounceSeconds:
                # button pressed for a shorter time, reboot
                call(['shutdown', '-r', 'now'], shell=False)

# subscribe to button presses
GPIO.add_event_detect(shutdownPin, GPIO.BOTH, callback=buttonStateChanged)

while True:
    # sleep to reduce unnecessary CPU usage
    time.sleep(5)

Mario77, Da Flex,

Your explanations are very useful. I was thinking to implement such a button on my Pi4 BUT I was thinking... What if the power button is with IR for the regular TV or Bluetooth from the phone. Is this possible to be done? I think this will be just a bit better for usage

Thanks again for your explanations!

Quote from Nayed

Mario77, Da Flex,

Your explanations are very useful. I was thinking to implement such a button on my Pi4 BUT I was thinking... What if the power button is with IR for the regular TV or Bluetooth from the phone. Is this possible to be done? I think this will be just a bit better for usage

Thanks again for your explanations!

That will be usefull just for startup if it works...basically reboot and shut down are the same as the ones you r using now from Kodi power menu..so you can set the remote buttons even without switch..

Just a quick idea is a transistor between pin 5 and 6 and an ir receiver connected to it...basically if you short pin 5 and 6 rpi will start.

Quote from Mario77

That will be usefull just for startup if it works...basically reboot and shut down are the same as the ones you r using now from Kodi power menu..so you can set the remote buttons even without switch..

Just a quick idea is a transistor between pin 5 and 6 and an ir receiver connected to it...basically if you short pin 5 and 6 rpi will start.

True for the reboot and shutdown. In fact I am using the Kodi app on the phone as a remote control but for the activation I can not use it

So you said just shorting pin 5 and 6 will start rpi( you mean GPIO3 and GND)??? Directly shorting them with nothing else?

Quote from Nayed

True for the reboot and shutdown. In fact I am using the Kodi app on the phone as a remote control but for the activation I can not use it

So you said just shorting pin 5 and 6 will start rpi( you mean GPIO3 and GND)??? Directly shorting them with nothing else?

Yeah thats what I mean gpio3 and the gnd across it...you add dtoverlay=gpio-shutdown to config.txt..

Quote from Mario77

Yeah thats what I mean gpio3 and the gnd across it...you add dtoverlay=gpio-shutdown to config.txt..

If I want just to start rpi only do I need to add the dtoverlay=gpio-shutdown to config.txt. and 1 maybe stupid question - where is this config.txt file on pri4

Quote from Nayed

If I want just to start rpi only do I need to add the dtoverlay=gpio-shutdown to config.txt. and 1 maybe stupid question - where is this config.txt file on pri4

To power up, all that’s required is to connect physical pin 5 (BCM 3) to the ground next to it. This functionality is enabled by default.

To shut down with the same button, just add the line dtoverlay=gpio-shutdown to /flash/config.txt

config.txt is read only

to edit ssh

mount -o remount,rw /flash

then to make it read only again

mount -o remount,ro /flash

Quote from Mario77

To power up, all that’s required is to connect physical pin 5 (BCM 3) to the ground next to it. This functionality is enabled by default.

To shut down with the same button, just add the line dtoverlay=gpio-shutdown to /flash/config.txt

config.txt is read only

to edit ssh

Code

mount -o remount,rw /flash

then to make it read only again

Code

mount -o remount,ro /flash

Millions of Thanks!!!

Quote from Da Flex

Create this /storage/scripts/status_led.py :

Python

#!/usr/bin/python

import sys
sys.path.append('/storage/.kodi/addons/virtual.rpi-tools/lib')
import RPi.GPIO as GPIO

# Replace YOUR_CHOSEN_GPIO_NUMBER_HERE with the GPIO pin number you wish to use.
# Make sure you know which rapsberry pi revision you are using first.
# The line should look something like this e.g. "gpio_number = 7".
led_gpio_number = 13

# Use BCM pin numbering (i.e. the GPIO number, not pin number).
# WARNING: this will change between Pi versions.
# Check yours first and adjust accordingly.
GPIO.setmode(GPIO.BCM)

# Switch LED on.
# LED will switch off automatically at shutdown by using normal GPIO state.
GPIO.setup(led_gpio_number, GPIO.OUT)
GPIO.output(led_gpio_number, True)

Display More

Thank you very much for the guide!

I came up with a problem that after I changed the led GPIO to 4 (BCM Mode), the LED was blinking slightly when Pi shutdown. But GPIO 13 works well. I can hardly find anything about the GPIO state after Pi shutdown. Is there any way to solve it cause I want to make the wires more concentrated.

Thank a lot!

It's strange. I am running the LE 10 Nightly (currently 20210703) on RPi 4B, using output GPIOs 4, 6 and 27 for relays and LED, also in BCM mode and did not encounter any issue so far.

There's a difference between GPIO pins so it may play a role... For instance, GPIO 13 supports hardware PWM while GPIO 4 does not.

GPIO - Raspberry Pi Documentation

Hello and thanks for all the tip here. Just one thought, can i change dtoverlay=gpio-shutdown to dtoverlay=gpio-reboot if i just want to get the pi out from halt and just reboot?

Quote from 2469

Hello and thanks for all the tip here. Just one thought, can i change dtoverlay=gpio-shutdown to dtoverlay=gpio-reboot if i just want to get the pi out from halt and just reboot?

Sure. First try without keyboard.xml. If you get a menu screen instead of instant reboot, use keyboard.xml, and replace shutdown by reboot.

Da Flex : I am also looking for, a way to shutdown LE with a button, so I came on this toppic.

Connected a button on pin 5 and 6, of the GPIO, and startup from standby, worked by default. Added dtoverlay=gpio-shutdown to config.txt, also made and added, /storage/.kodi/userdata/keymaps/keyboard.xml, after reading this toppic
Via SSH:

mount -o remount,rw /flash

(added dtoverlay=gpio-shutdown to config.txt)

mount -o remount,ro /flash

reboot

But, startup still works, shutdown does not, also tried several other syntaxes, like leaving the “=”sign out(as Allissonhsp, suggested) ,or adding ,gpio_pin=05 to the line(on my own accord, looking at the line for ir on pin 18) but still nothing happens after reboot. Now, I'm not an absolute beginner, but scripting is so not my Forte.

I’m working LE 11.0.3 with Kodi-Nexus on a RPI 3b. What am I missing?

Wht don't you try gpiozero Button..more flexible....you can add short press reboot,long press shutdown etc