Weird Laser Mode

Phaedrux

Perhaps a feature request? I'm not certain but I think it was a safety thing.

pauledd

In laser mode (M453), M3 never turns on the laser immediately. Instead it sets the default laser power for following G1/G2/G3 commands. Likewise, M5 does not immediately turn off the laser, it sets the default laser power for following G1/G2/G3 commands. If a subsequent G1 command has a S parameter, the value of that parameter becomes the default laser power for that command and subsequent G1/G2/G3 commands.

So this code should set laser power to 1 and the laser should go on when the laser is moving:

M452 C"!exp.heater3" R255 F1000		; enable LASER mode
G90
M3 S1
G1 X20 F200
G1 X0 F200
G1 X20 F200
G1 X0 F200
G1 X20 F200
G1 X0 F200
G1 X20 F200
G1 X0 F200
G1 X20 F200
G1 X0 F200
M451								; enable FFF mode

But it doesnt. I found out that the S parameter in G1 seems mandatory to get the laser ON while moving... This makes the M3 command totally useless.
Furthermore software like FlatCam outputs gcode that uses M3 exclusively to set Laser Power before and after movements of the laser.

So if my understanding is correct you either use "G1 .. Snnn .. " commands or you are lost... or contact every developer of other gcode producing software to adapt this G1 Snnn command...

Then I would really consider to go back to RRF 2.03

Phaedrux

That's from the 2.03 release notes, which is the version you were running before, wasn't it?

Laser mode: for safety, the G1 S parameter is no longer sticky by default. You can make it sticky by adding parameter S1 to the M452 command.

From 2.04

In Laser mode, if sticky laser power mode is selected, the power set by the S parameter in a G1 command is remembered across G0 moves to the next G1 move

@pauledd said in Weird Laser Mode:

M452 C"!exp.heater3" R255 F1000 ; enable LASER mode

You're missing the S1 on your M452 command to enable laser mode.

https://duet3d.dozuki.com/Wiki/Gcode#Section_M452_Select_Laser_DeviceMode

https://duet3d.dozuki.com/Wiki/Gcode#Section_M3_Spindle_On_Clockwise_CNC_specific_Laser_on_Laser_specific

g0rg

@Phaedrux said in Weird Laser Mode:

That's from the 2.03 release notes, which is the version you were running before, wasn't it?

Laser mode: for safety, the G1 S parameter is no longer sticky by default. You can make it sticky by adding parameter S1 to the M452 command.

From 2.04

In Laser mode, if sticky laser power mode is selected, the power set by the S parameter in a G1 command is remembered across G0 moves to the next G1 move

@pauledd said in Weird Laser Mode:

M452 C"!exp.heater3" R255 F1000 ; enable LASER mode

You're missing the S1 on your M452 command to enable laser mode.

https://duet3d.dozuki.com/Wiki/Gcode#Section_M452_Select_Laser_DeviceMode

https://duet3d.dozuki.com/Wiki/Gcode#Section_M3_Spindle_On_Clockwise_CNC_specific_Laser_on_Laser_specific

Thanks to your post my laser is now up and running on duet wifi rrf 3.1.1 .
Thank you very much

pauledd

@Phaedrux said in Weird Laser Mode:

You're missing the S1 on your M452 command to enable laser mode.

Thanks, I totally missed that somehow...

Still I dont know how to focus my laser while it is moving could be
a little bit tricky

Maybe I'll heft my function generator to the laser module to enable it to 1/255th pwm for focusing

~~I opened a issue regarding the M3 command...~~

pauledd

@pauledd said in Weird Laser Mode:

Still I dont know how to focus my laser while it is moving could be
a little bit tricky

~~I found a way to do it without moving it, assigning laser pin to a free fan pin and control it via M106 command:~~

### DOES NOT WORK ###
; disable Laser Mode
M451
; assign laser pin to a free fan Number
M950 F2 C"!exp.heater3" Q1000
; enable laser with 1/255th power
M106 P2 S1
; do the focusing stuff
; disable laser
M106 P2 S0
; free heater3 again for use in laser mode
M950 F2 C"nil"
### DOES NOT WORK ###

Just found out something is wrong again, after setting "M106 P2 S1" the heater3 pwm goes to 0,491V but it should read 0,02V...
Also the voltage does not change from pwm 1 to 25.
At 26 I then read 0,5V, at 27 0,52V and so on up to 254.
I dont get it, I'll give up for now, using my function generator...

Phaedrux

@pauledd said in Weird Laser Mode:

; disable Laser Mode
M541

Do you mean M451?

pauledd

@Phaedrux said in Weird Laser Mode:

Do you mean M451?

Yes

Phaedrux

Does that make a difference to your attempt?

pauledd

No, the command was just there IN CASE I still have the laser mode enabled.
If laser mode was not enabled the wrong command would have no effect anyway...

Phaedrux

@pauledd said in Weird Laser Mode:

after setting "M106 P2 S1"

I wonder if this is because S1 is the same as S255?

S1 or S0 for on and off, or S0.1 to S1 in decimal values to act as a percentage, or 2-255 as an 8bit value.

I wonder if it would behave differently if it was configured as a servo i/o pin and controlled with M42 instead.

https://duet3d.dozuki.com/Wiki/Gcode?revisionid=HEAD#Section_M42_Switch_I_O_pin

pauledd

@Phaedrux said in Weird Laser Mode:

I wonder if it would behave differently if it was configured as a servo i/o pin and controlled with M42 instead.

That is definitely worth a try, I'll test that tomorrow, thanks.

Phaedrux

@pauledd said in Weird Laser Mode:

exp.heater3

I'm not sure if it would matter either but there are other expansion heater pins to try. I don't know if all are created equal.

pauledd

I tried exp.heater3 as servo pin and I detached my laser inverter logic just to be sure this is not another error source...

from a fresh booted Duet...

; initial voltage 3.276V on exp.heater3
M950 P0 C"exp.heater3" Q1000 ; voltage now at 0.0005V
M42 P0 S1 ; 3.310V  ??? WTF
M42 P0 S2 ; 0.0274V check!
M42 P0 S3 ; 0.0402V check!
M42 P0 S4 ; 0.0529V check!
M42 P0 S5 ; 0.0658V check!
M42 P0 S128 ; 1.656V check!
M42 P0 S253 ; 3.274V check!
M42 P0 S254 ; 3.287V check!
M42 P0 S255 ; 3.302V check!

So, except M42 P0 S1, which is exactly what I want... everything else seems to work.
The same strange behavior happens if I reverse the logic:

M950 P0 C"!exp.heater3" Q1000 ; voltage now at 3.302V
M42 P0 S1 ; 0.0005V  ??? WTF
M42 P0 S2 ; 3.274V check!
M42 P0 S3 ; 3.262V check!
M42 P0 S4 ; 3.248V  check!
M42 P0 S5 ; 3.240V check!
M42 P0 S128 ; 1.646V check!
M42 P0 S253 ; 0.0267V check!
M42 P0 S254 ; 0.0138V check!
M42 P0 S255 ; 0.0005V check!

pauledd

@Phaedrux said in Weird Laser Mode:

I'm not sure if it would matter either but there are other expansion heater pins to try. I don't know if all are created equal.

The problem is, my laser pcb pinout has been designed according to
alt text
which involves exp.heater3

Phaedrux

@Phaedrux said in Weird Laser Mode:

S1 or S0 for on and off, or S0.1 to S1.0 in decimal values to act as a percentage

It's exactly as I said. S1 is full on. As you see from your voltage?

pauledd

Thanks, I again missed that, so I will mark S1 & S0 as NOT PWM in my brain.
I was irritated because I worked with the M3 S1 command over a year and that did not set the laser to FULL power, insead it used 1/255th PWM...

So then PWM value 2 is the lowest possible setting for my laser... I think I can live with that.

Phaedrux

@pauledd said in Weird Laser Mode:

So then PWM value 2 is the lowest possible setting for my laser... I think I can live with that.

Possibly. I'm not sure how many decimal places you could get. Try 0.01.

g0rg

my laser mode worked correctly just once until i moved it to the enclosure
I dont understand where or what could i missed.

Now the laser is always ON with 3.6 volt on heater3 pin

btw, i use the same added small board and my version is rrf3 on duet2 wifi.
here is my config.g

; Configuration file for Duet
; executed by the firmware on start-up
; WorkBee Firmware Version 1.0.7

; Configure Connection - ENABLE ONLY ONE OF THE BELOW THREE
;M552 S1 ; Enable Wifi Network
;M552 S2 ; Enable Access Point Mode
;M552 S1 P192.168.2.14 ; Enable Ethernet - Change IP Address to suit
M552 S1 ;
;	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-

; DO NOT CHANGE ANY OF SETTINGS BELOW
; TO MAKE A CHANGE, COPY THE LINE OF CODE, PASTE IT INTO customconfig.g. THE CHANGE CAN THEN BE MADE IN customconfig.g
; ANY ADDITIONAL SETTINGS SHOULD BE PUT IN customconfig.g


; General preferences
;M453 				; Put the machine into CNC Modes
M452 C"!exp.heater3" R255 F9000	S1	; enable LASER mode

M575 P1 S1 B57600 ; PanelDue for RRF3
M550 PWorkBee CNC Machine 	; Set machine name
G90 				; Set absolute coordinates


; Network
M586 P0 S1 			; Enable HTTP
M586 P1 S0 			; Disable FTP
M586 P2 S0 			; Disable Telnet



; Configure Drives
M569 P0 S0 			; Drive 0 goes forwards
M569 P1 S0 			; Drive 1 goes forwards
M569 P2 S0 			; Drive 2 goes forwards
M569 P3 S0 			; Drive 3 goes forwards                        
M584 X0 Y1:3 Z4 U3 P3 		; Apply drive mapping to axes


; Configure Axes
M92 X400 Y400 Z400 U400 	; Set steps per mm
M350 X16 Y16 Z16 U16 I1 	; Configure microstepping
M566 X100 Y1000 Z1000 U1000 	; Set maximum instantaneous speed changes (mm/min)
M203 X4000 Y4000 Z2000 U4000	; Set maximum speeds (mm/min)
M201 X120 Y120 Z150 U120	; Set accelerations (mm/s^2)
M906 X2100 Y2100 Z2100 U2100 I50 ; Set motor currents (mA)


; Configure Axis Limits
M208 X0 Y0 Z0 S1		; Set axis minima
M208 X1300 Y1270 Z85 U1270 S0 	; Set axis maxima



; Configure Endstops	
M574 X2 S1 P"xstop"   ; X min active high endstop switch
M574 Y1 S1 P"ystop"   ; Y min active high endstop switch
M574 Z2 S1 P"zstop"   ; Z min active high endstop switch
M574 U1 S1 P"e0stop"  ; U max active high endstop switch	 
			 
; Other Settings
M140 H-1 			; Disable heated bed
M564 S1 H0 			; Disable jog commands when not homed
M911 S21.0 R23 P"G91 G1 Z3 F1000" ; Configure power loss resume
M501 				; Load Stored Parameters 
M98 Pcustomconfig.g 		; Execute custom config settings

any idea ?

pauledd

@g0rg Can you double check that you attached the small board to the correct pins?
I had the same case were the laser was always on until I noticed that the pin-socket that goes into duets expansion header was attached with a offset by one pin...