Craftbot filament sensor

This filament sensor contain 2 switches (20mm)
- one for run out or break of filament
- the secont for a filament jam

Both switches an be connected in sequence: 1st normally open, the 2nd normally closed.

Enable pull up resistor with gpio -g mode 21 up (I used BCM pin 21)
Check working IO with gpio readall

You can use it wit Octoprint. The Plugin "Filament Sencor Reloaded" pause the Craftbot and resume the print on command.

Part 3 needs to be clued on part 1. Part2 (just a cover) can be scewed with the switches.