Okay. I think everything should be working correctly now.
If you want to reverse the motors again you can. Just switch $3=0 if you want.
So to fix all my misunderstanding before…
0,0 should be at home… and number will increase positively down and to the left. The whole thing got muddled in my brain.
So looking back at the messages everything was fine 3 hours ago. Sorry about that.
Still moved the laser into the switches. If I set $3-0 the jogging is backwords.
Did you reverse the wiring as well?
no… I will try that
Yeah… Mean to put that how it was and to reverse out the $3. That was a wild goose chase.
so that would mean 00 is the back right and not the front left?
Right. Home position should be 0,0 in spite everything I said earlier. 
Numbers should increment positively as you go left and down.
ok…so that means we are working. Thank you so much for your help
It sounds that way yes. Now you get to have some fun and really start getting frustrated. Haha. Enjoy.
I remember seeing on grbl/shield posts that you should be using normally closed switch. You can set this in grbl. Most limit switch have 3 connectors, accommodating for normally closed and normally open. Advantage of normally close is 1st, if your circuit is open somewhere it will detect it. Second is that it is less prone to problems related to static or wires running close to ac wire. A capacitor should be added in this case.
You are correct Paul. My switches are wired normally closed.
Both ‘wired or’ and ‘wired and’ are used in industry. A NO or ‘wired or’ is much more common, probably because with early CNC equipment it used less wire and is simple to implemented. Since most of these were metal machines one wire would suffice to support a limit switch as the other side is just grounded. NO switches can be ‘paralleled’ for limits at both ends of the axes.
A ‘wired and’ required you to run voltage to the switches and back to the controller, multiple switches have to be connected in series to function properly.
I would think something being ‘pulled to ground’ would have a lower impedance than a supply voltage line, indicating it should be less prone to induced noise.
Most of these controllers today ‘sink’ current, they don’t supply it. And most of the protection circuits work on a ‘wired or’ type configuration with ‘active’ being the low state.
Both will detect an ‘open’ circuit during the homing cycle and ‘fault’.
100% of my machines use a ‘wired or’ or a NO type of switch.
Good luck, have fun…
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