I've been thinking about how I could use an IR beam breaker system placed on my hot-end electronics panel to detect when filament has gone crazy and stop the print so I have no fear about leaving the printer unattended.
I already have the heater block thermistor connected to my microcontroller so I'm assuming if I drive the input to the A/D to Vdd the duet firmware will throw an error and stop the print? (I'm typing this just to give me something to do during a long print job so I can't find out by experiment right now).
What would be super useful is if the Duet Web Control could push an email notification (better still SMS text!) to notify that things went wrong.
RS Components Reprap Ormerod No. 481
