Schematic of the Protooner Ver 3.00 stepper driver board

I have 2 of the headline boards, Protooner Ver 3.00, in operation. Now I would like to connect a pause signal from a temperature monitouring second UNO. My idea is to run my CNC sketches, watching the temperature of the spindle motor of the mill. At too high temperature my sketches will raise Z-axis, the tool out of the work piece and cut off the spindle motor power until it has cooled down some 20 - 30 degrees Celcius. Then the spindle motor power will be turned on, Z-axis returned to its working positiond and the CNC sketch will continue.

On the board SCL and SDA, 2 of the analog pins, 4 and 5, or 0 and 1, exist. Where can I find the other 4 analog inputs, except from soldering directly where the pins to the UNO are soldered?

There are digital I/O being free but they have special meanings for Estlcam using Grbl version 0.9 - 1.1 that I use occasionally. I would like to find a free input for my pause signal that hopefully doesn't jam up Estlcam.

Anybody knowing that board?

Here is the Uno to CNC shield pin out that shows to which CNC shield pins are connected to the analog inputs.

uno cns shield pinout.jpg

Tanks a lot gF!
I can't log in from the Pc but in my new phone it works.
I want to connect three pots for manually positioning my cnc mill without loosing the connectivity with Estlcam. Putting the pots in a high level state will make things work.

Hi gF!

Now I'm working on connecting end limit switches for the x-, y- and z- axles. The Protooner board has connections for limit switches at the opposite side of the USB connector. There it's printed "End switch" divided into X+, X-, Y+, Y-, Z+ and Z-.
Sending logic levels into X+, Y+ or Z+ makes the Uno read all those 3 signals at pin 9, the X pin. I expected the signals to be found at pin 9,10 and 11. No connections where made to X-, Y- nor Z-.
What do I do wrong?
Best regards

Hi again gF!

I found the error. Now it works.