Y axis seems to be reversed on frame and run commands

I have a Monport 40w lightburn and it appears I have a setting screwed up. Homing works as it should but if I select Frame I get a grbl error: G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)
On or near line 2:
If I click start I get a slightly different error ALARM:2
G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)
On or near line 4:
Using the "move buttons shows z to be normal but y seems to be reversed which appears to be causing the error.
Grbl settings are:
$$

$0=10

$1=25

$2=0

$3=4

$4=0

$5=0

$6=0

$10=1

$11=0.010

$12=0.002

$13=0

$20=1

$21=1

$22=1

$23=5

$24=1500.000

$25=3000.000

$26=250

$27=25.000

$30=1000

$31=50

$32=1

$38=10

$100=160.000

$101=160.000

$102=800.000

$110=8000.000

$111=8000.000

$112=100.000

$120=500.000

$121=500.000

$122=20.000

$130=300.000

$131=200.000

$132=200.000

Any help on this would be appreciated!

Can you provide the following:

  1. Screenshot of Edit->Device Settings
  2. Run these commands in Console one at a time and return output:
$H
$I
$#
?

Note that the first command will home the laser so be prepared for it.


$h

ok

sys.aborts

MonPort

Grbl 1.1f [‘$’ for help]

$I

Monport

[VER:1.1f.20220907:]

[OPT:VMZL,35,254]

Target buffer size found

ok

$#

[G54:0.000,0.000,0.000]

[G55:0.000,0.000,0.000]

[G56:0.000,0.000,0.000]

[G57:0.000,0.000,0.000]

[G58:0.000,0.000,0.000]

[G59:0.000,0.000,0.000]

[G28:0.000,0.000,0.000]

[G30:0.000,0.000,0.000]

[G92:0.000,0.000,0.000]

[TLO:0.000]

[PRB:0.000,0.000,0.000:0]

ok

?

<Idle|MPos:0.000,0.000,0.000|FS:0,0|WCO:0.000,0.000,0.000>

ok

<Idle|MPos:0.000,0.000,0.000|FS:0,0|Ov:100,100,100>

ok

Note that the screenshot you have taken is from Edit->Settings, not Edit->Device Settings.

I don’t see a particular issue in the output of the other commands.

Can you confirm where the laser head moves to when homed?

Can you run the commands in Console and report back:

$H
G90
G0 X290Y190
?

Where was the laser head after homing and where did it end up after the G0 command?

The laser homes perfectly


$H

ok

sys.aborts

MonPort

Grbl 1.1f [‘$’ for help]

G90

ok

G0 X290Y190

ALARM:2

G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)

[MSG:Reset to continue]

ok

MonPort

Grbl 1.1f [‘$’ for help]

[MSG:‘$H’|‘$X’ to unlock]

MonPort

Grbl 1.1f [‘$’ for help]

[MSG:‘$H’|‘$X’ to unlock]

[MSG:Caution: Unlocked]

ok

ok

?

<Idle|MPos:0.000,0.000,0.000|FS:0,0|WCO:0.000,0.000,0.000>

ok

<Idle|MPos:0.000,0.000,0.000|FS:0,0|Ov:100,100,100>

ok
Laser head did not respond to the G0 X290Y190

  1. Where is the position of the laser head after homing?
  2. Your laser is misbehaving. Let’s try a different tack. Run in Console:
$H
G91
G0 X5 Y5
?

Return output.
3. In which direction did the laser head move?

$H

ok

sys.aborts

MonPort

Grbl 1.1f [‘$’ for help]

G91

ok

G0 X5 Y5

ALARM:2

G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. (Right-click the ‘Devices’ button to reset the connection)

[MSG:Reset to continue]

ok

MonPort

Grbl 1.1f [‘$’ for help]

[MSG:‘$H’|‘$X’ to unlock]

MonPort

Grbl 1.1f [‘$’ for help]

[MSG:‘$H’|‘$X’ to unlock]

[MSG:Caution: Unlocked]

ok

ok

?

<Idle|MPos:0.000,0.000,0.000|FS:0,0|WCO:0.000,0.000,0.000>

ok

<Idle|MPos:0.000,0.000,0.000|FS:0,0|Ov:100,100,100>

ok
Laser only moved on $H (it homed)

By the way G0 x5 y0 moved the head as requested, no error. The problem is the y axis seems to be backwards and throws an error

Also G0 X5 Y-5 does what G0 X5 Y5 is supposed to do. I cant figure out how to correct that without screwing up homing which is working normally…

I’m not sure if you’re deliberately avoiding answering but be candid if that’s the case.

To where does the machine home? What position is it in after homing?

Have you changed any configurations since receiving your machine?

How are you determining intent? In which direction does G0 X5 Y-5 move?

I’m sorry I somehow missed that question. The laser homes to x0 y0.
The G0 x5 y-5 moves it to x5 y5. And yes changes were made I downloaded a 40W-LB.zip from Monport and installed 40W-Lightburn-Device-Settings.lbdev. Supposed to set my up in Lightburn…

That’s not my question. Where physically in the laser (top-left, top-right, bottom-left, bottom-right) is the laser head positioned post homing?

Did you make any changes to the GRBL configuration? Any of the $$ values?

In which physical direction did this move? And are you absolutely certain that the end result was X5 Y5?

Laser homes to top left…
Been tinkering with the $ values trying to correct the problem. Not seen any $$ values…
Lightburn sees the homing position as x0 y0, top left. G0 X5 Y-5 moves the laser down and right and Lightburn sees it as X5 Y5

Okay. It would have been useful if you’d disclosed any changes that you had made.

Here’s what I think is happening:

  1. Your Y motor is inverted. Either the connector is in backwards or somehow the machine was shipped with inverted pins on the connector.
  2. You flipped Y homing direction to accommodate for this
  3. You have not flipped Y direction to deal with the repercussions of that

You have a couple of options:

  1. See if you can identify the hardware issue. This is probably the preferred route in case you ever get updates from Monport. If you don’t care about this you could move to the second option. [EDIT] - note that if you do fix the connector that you’d have to revert the homing direction back to the original value.
  2. Change $3=6. Or go to Machine Settings->Y Direction pin invert ($3) and enable it.

That should leave you with a working system.

Can you please do one of the fixes, rehome, and then test jogging controls? They should work correctly.

It is homing AND framing properly now! Thanks, I will keep an eye out for anything else weird but the main problem is gone

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