laser engrave

yuval

hello everyone, im trying to setup laser module
this is my setup:
; Laser module settings
M563 P2 S"V" X3
G10 P2 Y0 V0 Z0 S0 R0 ; set tool 2 axis offsets
G10 P2 V0 Y0 R0 S0 ; set initial tool 2 active and standby temperatures to 0C
M106 P2 S0
M452 C"out9" R255 F500

im using diy idex printer which "U" corresponding to the laser tool head

the laser is not connected yet. im using voltmeter to measure the out9 pins

followed by the instructions manual, im sending the gcode:
g1 s255
or
t2 g1 s255

both of the gcodes doesnt change the PWM voltage at the out9 pin(out9 and ground)

any ideas?

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.