Shutdown app for (OpenAuto Pro +) CarPiHat

Work in progress. Don't blame me if you run down your car battery

This is dialog overlay for delayed shutdown of in-car system using RPi and CarPiHat.

• When ignition goes off, it'll for 2 minutes (by default), then;
• Popup a dialog onscreen with a second-by-second countdown from 20 seconds (by default)
• If user does not press the snooze button, RPi will nicely shut down on zero. Hitting snooze will dismiss the dialog for another 2 minutes (by default).

I have OpenAuto Pro running, but this Qt app is entirely independent of OpenAuto Pro.

Refer to CarPiHat wiki for more info on the CarPiHat's latched powerdown function. A simple Python script in included in CarPiHat wiki which safely shuts down RPi 10 seconds after ignition (IGN) has gone LOW.

Set up

1. Clone this repo

Easiest to clone out in /home/pi

git clone https://github.com/aegis1980/pyqt5_shutdown_CarPiHat.git

2. Install PyQt5

I found this to be easiest using apt-get, rather than using pip3.

sudo apt-get update
sudo apt-get install python3-pyqt5

3. Start script on startup

In the CarPiHat wiki the python script is set running from rc.local, prior to RPi Ui (and OpenAuto Pro starting).

Different here - we want to run the script after UI has started. Add the following at the end of /etc/xdg/lxsession/LXDE-pi/autostart:

python3 /home/pi/pyqt5_shutdownapp_CarPiHat/qt_shutdown.py live &

NOTE: If you don't pass live argument the deault is not go into debug mode.

To edit autostart:

sudo nano /etc/xdg/lxsession/LXDE-pi/autostart

4. GPIO setup

There is some setup of pins too (refer to CarPiHat wiki for more info). Add the following to /boot/config.txt

dtoverlay=gpio-poweroff,gpiopin=25,active_low

To edit config.txt:

sudo nano /boot/config.txt

Configuration

• You can change the snooze time (SNOOZE_TIME_MINS in minutes) and the on screen countdown time (ON_SCREEN_COUNTDOWN in seconds) at the top of the script. The defaults are 2 minutes and 10 seconds respectively.
• Included is some css-type styling for the snooze button and countdown. Not that experienced with Qt - guess you can make it look however you please.
• Default UI sizing is for the official RPi touchscreen, which is (only) 800x480 (UI_SCALE=1). Use UI_SCALE to scale up for higher resolutions (e.g. Full HD, 1980x1080: UI_SCALE=2.5). Default is x2.5 (for full HD)

Debug mode

Running without live argument runs in debug mode:

• Does not shut-down pi when countdown runs out. Just closes app.
• Snooze time set to 5 seconds
• Logging.