A header mounted push button that will safely shutdown the Raspberry PI
This project describes a very simple but very very usefull tool that allows you to safely shutdown your Raspberry PI. This might be particularly usefull when, for instance, your headless PI is unreacheable because your network/wifi-router happens to be down at the exact moment you need to shut down the PI ... you probably know what I mean... the question is then how to safely shutdown the PI without risking any SD card corruptions.
Now I didn't devised this setup, the credit all goes to GIMX where I found it. A bit of advertisement here:... GIMX is a cool project that allows old gamers, like me, to use the mouse and keyboard to play games on the PlayStation or XBox. Sounds like a gimmick doesn't it :-) !!!
I thought this was so usefull that I wanted to replicate it here so I would not loose it.
My meager contribution is repackaging the push button and the led to easily mount them on the PI header.
The led will turn on when a program of your choosing is running, in my case it is python...
Fritzing does not allow the kind of 3D drawing I need to explain how to mount the resistors and the push button (PB) on top of a dual inline 6 pins female header, sorry for the distorded "perspective" view...
Some pictures might help...
some epoxy glue visible on that one...
Of course there is a python script that handles it all, copy it in your /home/pi directory as blink.py.
To start the script blink.py at boot, add it to the pi user crontab (crontab -e) as:
@reboot python /home/pi/blink.py & .
I just installed Moode 8.3.1, which comes with an Airplay2 renderer, on a PI-3b 1.2 equipped with an IQaudio DAC Pro HAT. This allows my 2 old mid-2012 MACs, recently upgraded with the wonderfull https://dortania.github.io/OpenCore-Legacy-Patcher/, to VENTURA 13.3.1 no less, to stream music with Airplay2.
The push button and the led work as before but in order to start the script at boot time you will have to add as root, at the end of /etc/rc.local, and before exit 0 : (/home/pi/blink.py)& as is, with the the brackets and all. I got this from https://www.msldigital.com/pages/shutdown-scripts-for-moode-audio .
After some issues with the Airplay renderers, I found out a simpler, and most satisfying setup, based on Spotify's "connect to a device" feature, which allows to play tunes on the RPI IQaudio DAC, from another computer's browser.
First install the latest PI OS (cat /etc/issue => Raspbian GNU/Linux 11 \n \l) on your PI. To make sure the IQaudio DAC is the default audio player comment out dtparam=audio=on, add dtoverlay=iqaudio-dacplus and dtoverlay=vc4-kms-v3d,noaudio in /boot/config.txt:
...
...
# Enable audio (loads snd_bcm2835)
#dtparam=audio=on
dtoverlay=iqaudio-dacplus
#dtoverlay=rpi-dacpro
# Automatically load overlays for detected cameras
camera_auto_detect=1
# Automatically load overlays for detected DSI displays
display_auto_detect=1
# Enable DRM VC4 V3D driver
dtoverlay=vc4-kms-v3d,noaudio
max_framebuffers=2
...
...
We need to remove pulseaudio as it breaks up things ...
sudo apt-get remove --purge pulseaudio
Reboot your PI, and from any PC or MAC, access it with VNC, and start a Chromium session to connect to the "Spotify web server" URL. Once connected to Spotify, test if it's playing on the DAC, then you can close the VNC session to your PI if you want to but don't close the Spotify web page.
Then on any PC or MAC computer, from any browser, again connect to the "spotify web server" URL, and at the bottom right hand corner, click the "speaker box like icon" displaying "connect to a device" and click "web player (Chrome)" which is still running on your PI. From now on, any tunes you choose will be played on the Pi's DAC ... ain't that cute !
That's it, from any browser on any of your in house computer, you can now play music on the PI IQaudio DAC without the proprietary Airplays ...
jrb.