laser engrave

jay_s_uk

@yuval what firmware version are you running?

yuval

@jay_s_uk im using firmware version 3.3

jay_s_uk

@yuval in which case to use laser mode you will have to switch RRF into that mode using M452 whenever you need to use the laser https://docs.duet3d.com/User_manual/Reference/Gcodes#m452-select-laser-device-mode

yuval

@jay_s_uk im not sure i understand what you said

As ive wrote above, i am using m452 ("M452 C"out9" R255 F500")

so, in order to activate the laser, i should send the gcode :
M452 C"out9" R255 F500
t2 g1 s255

and yet, i measure 0v from out9 to ground

jay_s_uk

@yuval sorry, i misread.
you can't measure PWM with a voltmeter (not quick enough). you'd need an oscilloscope or the like

yuval

@jay_s_uk but wait, if ill try to enable the laser full power, s255, i should read 5v with any voltmeter, shouldnt I?

jay_s_uk

@yuval you should ready 5v at any power level. The only time you shouldn't read anything is when its off

yuval

@jay_s_uk i understand.
i ask you this:
if i set the pwm to 100%, any volmeter should be able to read the voltage.

therefore, i think somthing is wrong in my setup, because i read 0v even at 100% power

jay_s_uk

@yuval you can test the output using M42 if you're concerned it doesn't work.
(until recently) I ran my laser cutter on RRF so I know it works.
Are you using the Out9 connector or the VFD/Laser connector?

yuval

@jay_s_uk doesnt m42 work only on GPIO?

ive tried
M42 P"OUT0" S255/S1
M42"LASER" S255/S1

nothing changed..

jay_s_uk

@yuval you have to set the pins up with M950 first as described in the docs to use M42

yuval

@jay_s_uk i dont think the laser pin is bad.
i think somthing is wrong in my setup.
do you have any ideas on what could i do?

let's say ill test it with m42 and i see it works, what next? why doesnt it works normally?

dc42

@yuval said in laser engrave:

t2 g1 s255
and yet, i measure 0v from out9 to ground

The S parameter is intended to be used on G1 commands that also command movement, so you won't get any PWM output unless you command movement in that G1 command; then the laser will be on during that movement.