Lightobject.com Support Forum

I'm trying to configure all my settings in LaserCAD and I've run into an issue that I can't figure out.

I have my endstops wired for X-min and Y-max currently. They are wired as normally open with the ground to terminal 7's GND pin on my 608 DSP. When I enable "XY Home Axis on Power" my X-axis homes properly, but my Y-axis doesn't seem to move at all during the homing process to find the limit switch.

Additionally after homing every time I try to move the Y-Axis the LCD display beeps and shows the message "Trigger Limit!". Knowing that my X-min endstop is wired the exact same way and works I'm sure that the endstops wiring is not the problem. To check this I completely disconnected the Y-max endstop and tested with a brand new switch, same results. I've actually completely removed the y-max endstop so that there should be no signal going to the DSP that would trigger the "Trigger Limit!" message and it still displays every time I try to move my Y-axis.

The DSP acts like the Y-endstops are always grounded/closed even when there are no switches connected. Any suggestions from the group here or is something not right in the DSP?

Use X- and Y- for the HOME
That's it

Marco

I've tried both Y+, Y-, and no endstop all of the setups react the same way. It's not that the "Homing" process isn't triggering the Y-endstop. The Y-axis never even moves toward an endstop it just stays in once place as though an endstop is already held closed. Then when I try to move it with the keys it continuously says "Trigger Limit!" on the LCD screen when I'm in the middle of my table and not tripping any switches. I've tried brand new switches and tried to move the gantry without any switches attached too so I know my switches aren't the problem. That's why I'm wondering if I'm missing a setting or if my DSP board is messed up.

My X-axis and Z-axis endstops are wired the exact same way and are working perfectly for homing and any other movement I try to do. It's literally just the Y-axis endstops causing me the problems, could the circuitry for the Y-axis endstops be bad?

Thanks.

You can open the mainboard case to check the status of the X,Y limit status
Once X- or Y- ground, there is a LED reacted to it

When press "RESET", both X and Y should move forward to the HOME location, wasn't it?


Marco

Hi Marco,

Thanks for the tip. After opening up the case the LEDs function as you would expect for all of the limit switches, that is to say they only light up when I push the switches down.

That said I'm still having the homing issue. When I plug the DSP in the X-axis moves to the limit switch, hits it, backs away and then pauses. When the Y-axis should be doing the same it doesn't move at all and then the X-axis slowly moves towards the endstop again. I know it's supposed to move 3 times X, Y, X, Y, X, Y. That's not happening, it's just X, no Y movement, X, no Y movement, X, no Y movement.

Could this be a software glitch? I updated the DSP to the latest firmware before I started using it. I've just run out of things to check and now seeing that the switches are functioning properly via the LEDs I'm not sure where to go from here.

Thanks.

Hi Marco and others on the Forum,

Just wanted to check in and see if anyone had any advice based on the post above. Has anyone experienced this issue before?

Thanks.

Check the "Limit polarity" of the Limit switch. Are you using negative or positive on LaserCad parameter setup??
Make sure to use X- / Y- vs Ground and set LaserCAd to Negative

Is Y move at all? May be bad driver or motor?


Marco

I'm not sure why, but changing the Limit Polarity in the LaserCAD software settings seems to have solved the problem. My Y-axis was positive and when it was set to the the axis wouldn't move anywhere without throwing the "Trigger Limit" error. Now being negative the Y-axis moves and homes just fine.

Is this because to the DSP and LaserCAD negative is ground and positive is an open circuit? Just trying to better understand the software and where I went wrong.

Thanks Marco for the help.

Now I just need to dial everything in to get the proper steps and speeds.

Thanks to Marco's help I was able to get the homing routine worked out and I'm no longer getting the "Trigger Limit" error.

I have however come up with one more question I was hoping someone could help with. I've limited my table size in the LaserCAD software to X:700 and Y:500 and saved it to the DSP, but for some reason after the table does the homing routine it tries to go to a position of X:885 and Y:425. Obviously that works fine for my Y-axis, but it crashes the X-axis into the end of the rail. Is this a behavior that anyone else has seen before? Is there a software setting that I can configure to stop this or change the position it tries to move to after homing? I haven't found anything yet.

Thanks Again.

It wants to go back to the original orgin that is now outside your current limits. after it homes press the Stop button and then hit Orgin. It should go to the new origin after you reset the controller.

Thanks for the tip. The stop button didn't stop the gantry from crashing, but your comment sparked a thought in my mind.

I remembered seeing Origin settings in the LCD Menu. I was able to go into those settings once movement stopped and Origin1 was in fact set to the 425,885 point. I've cleared it out and everything is homing without crashing now.

Thanks Telrad. Now I really do just need to dial in my speed settings.