Strange problem, and I don't know how to address it.

[regpye]

This one has me puzzled, maybe someone can help?

I am setting up a new laser engraver, using GRBL, Arduino UNO and CNC shield. The shield has a double Y axis using a cloned A driver. I am using LaserGRBL to control GRBL 1.1h in laser mode (I actually have laser mode turned off during testing so I can do some things that laser mode will not do while not in motion)

I had all the setting done correctly I thought, I could move the machine in all the correct directions and then I came to doing the homing.
I pressed the homing button and all moved in the right directions, Z was OK, Y gave a problem (not worked that one out yet) and X didn't complete due to Y having the problem. I will check out all the wiring and connections tomorrow when I have more time as it is late here now.
The strange problem is that after trying to home, the X and Y axis will now only move in a positive direction, no matter which direction I try to move in. The Z will work OK in both directions. If I try homing again, it will home in the negative direction, so the motors and drivers seem to be OK.
I reset the program (LaserGRBL) and I even closed the program and restated it again, shut the computer and the machine down and restated them again, but still the problem persists.
I am at a loss to work out what has happened. I guess I wont get much sleep tonight thinking about it.

[gilshultz]

Sorry I will not help you get any sleep. This may be very clear to you but I do not have a clue what you are asking. Please post a complete schematic, not a frizzy thing, including all power supplies, power, ground and interconnections. Post links for the hardware parts.

[Ballscrewbob]

It sounds like you have not yet set up the bounds for the machine table size.
If it is a home brew CNC machine there are plenty of ready made answers for issues with grbl and limit switches you can find using the SEARCH option at the upper right of the screen.

[regpye]

ballscrewbob:
It sounds like you have not yet set up the bounds for the machine table size.
If it is a home brew CNC machine there are plenty of ready made answers for issues with grbl and limit switches you can find using the SEARCH option at the upper right of the screen.

The bounds have been set and set very accurately. It is not the first "home brew" machine I have built, in fact I have built many, but I have never experienced this problem before and that is why I reached out here thinking that there maybe someone that could shed some light on what is going on. Thanks for the search advice.