Marlin 515 not turning on the laser

Software / Firmware
1
  • Inline laser commands. 8bit can do 22mm/s raster, 32bit 25mm/s raster. Vector much faster.

I’m running a Rambo board using g-code generated by Lightburn.

Based on Ryans comment, I decided to upgrade to Marlin version 515 to see if I noticed a difference. When I ran a g-code file on 515 (that works with Marlin 513), the laser just doesn’t come on. M3/M5 g-codes work in 515. Looking at configuration_adv.h, all the “INLINE” defines have been removed, so I’m assuming that inline laser support is always on now if laser support is enabled? Anyone have a Rambo board and a laser working with 515? Any suggestions on debugging the problem? I did roll back to 513, and verified the same g-code file works correctly again.

2

What does your gcode look like?

It is a tiny bit different now but I am trying to remember how. Let me find my example.

3

Now for whatever reason it seems when you do use just M3 (not M3 I) accelerations are enabled for the change in laser power so it is a burnt mess.

Yeah so before we used to just use “M3”, now it needs to be “M3 I” So you can can easily edit any previous files you have by adding that “I”.

Here is my Gcode, and it ends with an M5.


;USER START SCRIPT
M3 I
;USER START SCRIPT

G21
G90
; Image @ 22 mm/sec, 32% power
M9
M05
G0 X2.379 Y2.934 F0
; Layer C00
G91
G1 X1.65 F1320 I S0
G1 X46.63 I S10.2
G1 X1.65 I S0
G1 Y0.19 I S0
G1 X-1.65 I S0
G1 X-46.63 I S10.2
G1 X-1.65 I S0
G1 Y0.189 I S0
G1 X1.65 I S0
1 Like
4

Thanks for the info. In your g-code snippet, ‘S’ power is ‘10.2’? I see 0 to 255 in my current Lightburn g-code. Has the range of PWM values changed also?

5

No I don’t think so. I am not sure where That Gcode is actually from so I am not sure what the .2 is. I have marlin set 0-255 and grbl 0-1000. From what I remember.

6

Are you able to use the firing while framing with Inline set? I’m only able to do it if M3/M5 is selected. I’m able to burn with Inline which works fine but it won’t fire while framing the project.

Also I notice after I burn a project, it will fire for framing but toggle firing off/on when it hit the corners of framing. I have not tried to roll back the firmware to 513 (2.0.7.3) but I don’t want to if I don’t have too. Just inconvenient to got to m3/5 to frame and select Inline to burn, could easily be forgotten and now the project will run much longer if kept in m3/5 mode.

7

To enable inline commands, you must have the following at the top of your file:

M3 I

This command can be inserted automatically by adding it to the start code section in Lightburn.

I ran some tests of M3/M5 vs. inline commands for both cutting and engraving, and inline produced far superior results, so you want inline.

Note that I run my jobs off the SD card, so if your issue is specific to driving your machine directly from Lightburn, I don’t have an answer for you.

8

Thanks, yes i can run either or M3/5 or inline (w/ M3 I start gcode) from lightburn or sd card as well. It’s just the framing feature I like about lightburn so I can maximize the stock and ensure it fits within bounds.