Turn laser only on?

pauledd · 2 Oct 2019, 08:44

Hi

I made great progress in wiring and connecting my test-laser to the duet
board as described in this tutorial and now I want to calibrate the laser focus.
As the laser is normaly controlled via G1 X.. Y.. S.... commands, how can I simply turn on the laser at a specific pwm value to adjust the focus point without movement in the X/Y axis?

dragonn · 2 Oct 2019, 10:41

Try M4 S255 or M4 S1

pauledd · 2 Oct 2019, 11:12

@dragonn said in Turn laser only on?:

Try M4 S255 or M4 S1

 Error: M4 command is not supported in machine mode Laser

EasyTarget · 2 Oct 2019, 12:33

I think; until some upcoming changes hit release, you need to disable laser mode while finding focus since any movement will kill the laser. This is by design, a good safety feature, but irritating when focusing or size checking.

I would create a macro for this that disables laser mode and sets the laser power to your focusing setting in one go. Dont forget a 'end' macro (Or M291/292 to confirm ending) to make things safe again afterwards.

pauledd · 2 Oct 2019, 13:14

@EasyTarget said in Turn laser only on?:

you need to disable laser mode while ...

Ok so I disable Laser mode by enabling another mode, I assume CNC because thats the only mode that works with M4 command...

So I do a "M453 P3 R255" to enable CNC mode on Heater3 with PWM max to 255. If I then issue a "M4 S10" nothing happens. The laser stays off...

EasyTarget · 2 Oct 2019, 13:48

@pauledd said in Turn laser only on?:
Using the default CNC mode is what I intended, yes.

If I then issue a "M4 S10" nothing happens

Sounds like an improvement over getting an error.
What happens if you do the same with M3?

M4 (reverse) has little application in for lasers.
It is used by some other firmwares to enable specific power modulation modes etc.

pauledd · 2 Oct 2019, 14:43

@EasyTarget said in Turn laser only on?:

What happens if you do the same with M3?

Works!
Can now turn ON/OFF the Laser with M3 S255, M3 S0
Thanks.

EasyTarget · 2 Oct 2019, 14:58

@pauledd said in Turn laser only on?:

Works!

Great!,
I just realised that M453 P3 R255:255 would also solve this by enabling M4; it's the 2nd option on the R parameter that does that.
But.. I've also found with CNC's that the important thing is to come up with a workflow that works, and not get too fussy about the details, that way lies madness.