Posts by pooh22

Quote from frakkin64

I believe Raspberry Pi OS automatically updates the EEPROM at boot, so perhaps that is what it took?

I guess that would do it.
There seems to be some confusion about the term "firmware", I thought it was the stuff that stays on the pi, rather than the sd-card, but it looks like it may be just "drivers" for the kernel in raspian. Or perhaps rpi-update calls the eeprom update as well?

Anyway, if it was the booting of raspberry OS or running rpi-update, it does boot when I press the button now...

I wonder what gives with the cec-client, perhaps the cable is the problem, as that's different with the one I used for the rpi3...

NB, I tried to do this same thing on the raspberry pi 4 (rpi4) and it doesn't work entirely the same.

The pi4 needs a recent firmware (the first ones produced have a firm-ware which doesn't let the power button works. If you have this problem, best use a different sd card with raspian to update the firmware with ``````rpi-update

Furthermore, the cec-client seems to have issues with some TV's or hdmi cables. And it's only supposed to work on the hdmi port closest to the powersupply port. For me (Philips tv), it still doesn't work. It could be the cable, the TV or something else.

For the most part though, it can work on the rpi4 as well.

I just created this for my setup, perhaps it is useful for others:

required items:

• rpi3 with libreelec
• switch (normally open) between ports 5 and 6 of the GPIO pins
• led between ports 6 (or some other GND) and 8 of the GPIO pins (TX uart) (add 330 ohm resistor)
• install package adafruit-libraries

The uart is off by default, so you need to turn it on in the config.txt

mount -o rw,remount /flash

Edit /flash/config.txt`` and insert the following somewhere logical

dtoverlay=pi3-miniuart-bt

```

create the following files

• /storage/scripts/off-button.py

`

#!/usr/bin/python
#This script was authored by AndrewH7 and belongs to him (www.instructables.com/member/AndrewH7)
#You have permission to modify and use this script only for your own personal usage
#You do not have permission to redistribute this script as your own work#Use this script at your own risk
import sys
sys.path.append('/storage/.kodi/addons/virtual.rpi-tools/lib')
import RPi.GPIO as GPIO
import os


gpio_pin_number=3
#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_pin_number=7"


GPIO.setmode(GPIO.BCM)
#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.setup(gpio_pin_number, GPIO.IN, pull_up_down=GPIO.PUD_UP)
#It's very important the pin is an input to avoid short-circuits
#The pull-up resistor means the pin is high by default
try:
    GPIO.wait_for_edge(gpio_pin_number, GPIO.FALLING)
    #Use falling edge detection to see if pin is pulled
    #low to avoid repeated polling
    #os.system("shutdown -h now")
    os.system("/storage/scripts/poweroff.sh")
    #Send command to system to shutdown
except:
    pass

GPIO.cleanup()
#Revert all GPIO pins to their normal states (i.e. input = safe)

• /storage/scripts/poweroff.sh

#!/bin/sh

echo "standby 0" | cec-client RPI -s -d 1 -p 0
shutdown -h now

Make both scripts executable:

chmod +x /storage/scripts/poweroff.sh /storage/scripts/off-button.py

Then make sure the off-button.py script is started when the rpi starts up:

• /storage/.config/autostart.sh

(
  python /storage/scripts/off-button.py
) &

After rebooting the rpi3, it should work.

Thanks to AndrewH7 of instructables for the python script and everyone on the internet who wrote about adding a power button with or without LED to the rpi.

(The only thing I added/changed was the cec-client stuff via an external script)