A few questions for my UCCNC UC100 with a leadshine MX4660 setup. My first cnc build!

1. Do I need to set metric or SAE for my units in the UCCNC? I don't see that as an option in manual or software. Is this all g-code driven from CAM software.. but then if I manually enter g-code of X100... what unit is 100? Inches, centimeters or millimeters?

My only other thought was that when you calibrate... your unit is whatever unit you use to measure the actual distance... so then you always have to output your g-code in the same units. UCCNC doesn't know or care what 100 is. In my case, I have 2510 and 2505 ball screws... even then it doesn't matter since calibration takes care of that... that's my assumption at least. Seems like a good way, you don't have know about the mechanical ratios and travel per turn... hopefully I'm right.

It's just not making sense from the docs.


2. Will "Port" settings always be 1 for the UC100... I'm mapping the Pin numbers to what my MX4660 needs, but I'm not sure if Port is just something for the UC300.


3. For limit and home switches I don't understand the "Active High" and "Active Low" stuff... is "Active High" when that configured pin goes from receiving 0 to 5 volts and that triggers the switch. "Active Low" would mean, it's triggered when it's receiving 5 volts but then the sensor stops sending the signal and it's now 0 volts?

In my case I'm using proximity sensors, NPN.NO with a 4mm inductance type. I'm guessing NO is for normally open, so when it's closed, it will send the 5 volts of current and I'll want to be "Active High"... so don't check the "active low" option.


Thanks for the patience with these newbie questions,.. my first cnc, lots of reading, digging through forums... I don't know what I don't know. Little stuff is hard at the moment, but I'm hopefully getting it. These may not even be uccnc specific.