Lightburn Profile that supports G1 Sxxx commands

The preferred way to control a laser using Duet/RepRapFirmware is to use S parameters in G1

This is said by David Crocker, the developer of RepRepFirmware.
I have a Duet controller running RRF3 in my newly built machine. I have everything working, and G1 Sxxx burns when I give manual commands in the console. However the Marlin profile (there is no RRF profile yet) does use M commands and G commands without S parameters. Is there a profile that puts out the G1 Sxxx commands like I need? I hear Grbl-M3 does that, but that one does not allow for many other Gcode commands like homing.


There will be for the next release:

The Inline setting uses M03 / M05 commands and G1 Sxxx for power in the Marlin profile.

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Great! You have an ETA on that?

I guess apart from this issue Marlin gcode is pretty compatible with RRF and since RRF3 has velocity ramping implemented, it is a great controller for laser and CNC, in addition to printing. This inline power feature will certainly decide me to buy Lightburn. (im am in trial now).


It would be nice though, if we could have ethernet connections in Lightburn too :wink:

You can, just not with that controller. :slight_smile:

We do plan to add proper support for the Duet, but it needs to be balanced against all the other development needs, and the expected return on the effort it takes to do it. If David wants to contact us, I can give him a beta build with the inline profile added and working for him to try.

I understand, and i read that before in this forum.

But I do think the Duet users are a fantastically loyal group to have, and are all about quality and participation. Duet3d hardware is considered top notch, and I think anybody with Duet experience is very reluctant to go “back” to any other hardware. I tried, using my old Rambo board with Marlin and Grbl, but I could not wrap my head around the usual Arduino configuration troubles anymore. I think your time-investment adding Duet support is very much worth it.

By the way, someone on the Duet forum pointed me to a configuration parameter to make the G1 S parameter sticky acros G1 commands. So currently I am runnng my first test burns :wink:

Can you share how you made the Sxxx sticky?

Oeh, it’s a long time ago. And in the meantime my machine stands unused in the shop for about 2 years now. But I was able to digg up what this was all about. It was about the M452 gcode command. Check the forum where I found that:

Well you have some catching up to do then. Turns out the inline option still only placed the power setting at the first G1 command where the power setting was different from the last. But hope is not lost, as I can confirm in the next release in the the GRBL device Gcode setting there will be an option to Emit S value with every G1 command. Thank you support for all your help in getting this implemented for the Duet community!

Yeah I really DO have some catching up to do… Once my lasermachine was almost ready I had to move it from my office to my workshop, and I never touched it after that :sob: Out of sight, out of heart… But I hope to pick it up again at some point.

Good to hear about the next release!