Filament sensor simplified

This plugin reacts to short lever microswitch output like this If triggered it issues configured command to printer.

Let's check some features:

pop-up notification when printer runs out of filament
very handy pop-up when printer requires user input while changing filament
test button so you know if your sensor really works or not
filament check at the start of the print - if no filament present it won't start printing, again pop-up will appear
filament check at the end of filament change - just to be sure you won't start printing with no filament
check if printer supports M600 when printer connected and gcode starts with M600 - if not user will be notified through pop-up
info pop-up when plugin hasn't been configured
filament runouts can be repeatable which didn't work with other plugins I tried
user-friendly and easy to configure
pin validation so you don't accidentally save wrong pin number
detection of used GPIO mode - this makes it compatible with other plugins
handles delibrate M600 filament change
runs on OctoPrint 1.3.0 and higher

NOTE: this plugin won't work if you use OctoPrint only to start printing from SD card

Setup

Install via the bundled Plugin Manager or manually using this URL:

https://github.com/luckyx182/Filament_sensor_simplified/archive/master.zip

Configuration

Configuration consists of these parameters:

GPIO mode - BOARD or BCM mode, BOARD mode - referring to the pins by the number, BCM mode - referring to the pins by the "Broadcom SOC channel", if this is selected by 3rd party, this option will be disabled with note on GUI
pin number - pin number based on selected mode
gcode to send to printer on filament runout - default is M600 X0 Y0
power input to sensor - input is connected to ground or 3.3 V
switch type - switch should be triggered when opened (input of the sensor doesn't transfer to its output) or triggered when closed (input of the sensor is transferred to its output)

Default pin is 0 (not configured) and ground (as it is safer, read below).

WARNING! Never connect the switch input to 5V as it could fry the GPIO section of your Raspberry!

WARNING! When using test button on input pin used by other application it will reset internal pull up/down resistor

Advice

You might experience the same problem as I experienced - the sensor was randomly triggered. Turns out that if running sensor wires along motor wires, it was enough to interfere with sensor reading.

To solve this connect a shielded wire to your sensor and ground the shielding, ideally on both ends.

If you are unsure about your sensor being triggered, check OctoPrint logs