Troubles using Marlin on Mega2560 + RAMPS 1.4

LightBurn Hardware Compatibility Marlin
1

Hello everyone !
I have different troubles, but I think they are all linked :wink:

My config : an home made machine used to print (3D plastic) and cut (laser), powered by Marlin 2.0 on a MEGA 2560 and Ramps 1.4. My laser is a Nejetool (model 30W). I use the latest version of LightBurn.

  • The laser doesnā€™t stop cutting between two shapes (even if LightBurn has well sent M05 command !!). In the same try, the laser correctly stop itself after the two shapes. Same problem if I add Tabs to a shape.
  • I am not able to use PWM on the laser. M3 or M4, whatever the value or not sent after, switch the laser at itā€™s maximum ā€¦ It seems logic because the laser TTL wire is plugged on the D4 pin. I think I should use D6, but the current is always at 1.48V on this pin (doesnā€™t react to M3/M4/M5 ā€¦).

I have three hypothesis :

  • Wrong configuration in Marlin
  • Wrong configuration in LightBurn
  • Issue(s) on my RAMPS or MEGA

Do you have any ideas ?
Donā€™t hesitate to ask me questions if needed :slightly_smiling_face:

Robin

2

In general I know lasering on Marlin is tricky business. What device type have you setup in LightBurn for the laser?

3

Thanks for the quick answer.
Iā€™ve done it manually, and used the ā€œMarlinā€ choice.
Iā€™ve changed my pins and I think I have a good result now !! Iā€™ll confirm in a minute or so.

4

I solved the issue but I donā€™t understand why ā€¦
I changed de PWM pin from 6 to 5 on the board and it works fine now !
I think my PIN number 6 it ill ā€¦ I have to investigate. For the moment I can use my laser for the Christmas Presents !

5

Do pins 5 and 6 both provide equal PWM capability?

6

I donā€™t know ā€¦ I think yes, they both are on a zone used for servos

7

Hello, can you please share the firmware and wiring?