I was getting the inductive probe working. After I tried my circuit, which worked but wasn’t quite reliable enough I decided to go back to the simpler resistor voltage divide option. Easy and foolproof.
It took me too tries because you really should give yourself enough prototype board to work with. It is hard enough figuring out what is going on when the parts are laid out simply, if they aren’t because you’re saving space it is simply a nightmare.
The new circuit worked great and I was getting set to put everything back together but the X axis stepper started to misbehave. I would vibrate instead of moving. I did some standard debugging and concluded I had a bad motor, sighed and ordered a new one.
This morning came the denouement as I turned on the printer and was met by a screech from the display. The display graphics didn’t show up and even after disconnecting the display it seemed that the controller board was broken.
And now I’ve RMA’d the board to Amazon for a refund and board a Smoothie board (well recommended) to replace the broken one. The smoothie is a different kind of firmware running on 32bit processor and doesn’t require the arduino IDE, compile and upload steps that the current board does. Instead I just need to modify the config file and replace it.
The actual board appears to be derived from the open sourced mks design.
My Gifted Life 