Specific working mode for CO2 laser on parameter $32!

[Deltaplc]

Good morning
Sorry to bother you....
I don't know if I've discovered hot water.....but I certainly think I've thought of(and tested) a valid solution to solve the problem!
I will try to explain myself with some examples, to help you better understand the problem that occurs when engraving images.
I have a home-made CO2 laser derived from a K40.

Example of engraving a photo in any mode (Stucki, Jarvis, dithering, etc.) except grayscale.

K40 operation "original configuration":
Fragment of a hypothetical gcode:
G1 X2.5F6000 off laser
G1 X0.1 on laser
G1 X20.5 off laser
G1 X0.1 on laser
G1 X2.5 off laser
G1 .....
The potentiometer (manual analog) supplies a constant voltage to the IN pin (pwm) and the board turns the laser beam on and off via the L (enable) pin.
Example of this configuration:
The sniper has his eye on the scope, always aimed at the target, and he only has to pull the trigger to shoot!
Result:
The IN pin is always at the desired voltage and already keeps the power supply "capacitors charged", it just needs to fire!

Custom laser with any board and firmware derived from grbl and with lightburn or lasergrbl software etc...:
Fragment of a hypothetical gcode:
M4
M3
G1 X2.5F6000 S0
G1 X0.1 S200
G1 X20.5 S0
G1 X0.1 S200
G1 X2.5 S0
G1 .....
The voltage on the IN(pwm) pin, varies from zero to S200, and the L(enable) pin, turns the laser beam on and off, following the strategy that depends on the M3/M4.

Example of this configuration:
The sniper must re-center his eye in the crosshairs every time he has to shoot and then pull the trigger!
Result:
The IN pin does NOT have a constant voltage, but varies between zero volts and S200,
the power supply "capacitors are not constantly charged" and when it fires it is not ready to immediately parry at the desired power!
General problem:
Loss of much detail when using dithering, Jarvis or similar methods at high speeds!

My thoughts Changes to be made to the firmware:
On the solution to this problem:

1. $32= 0 = CNC; 1= Laser ; 2= ​​Lathe ; 3=Laser_Co2
2. SPINDLE_ENABLE_PIN = Behavior unchanged, behaves as it does now.
3. SPINDLE_PWM_PIN = M3/M4 S.....= S1 / S1000 pwm regulation, does NOT consider the S0 parameter for pwm regulation.
4. M3 / M4 = Turns off with M5 or M2 command. (Now, if $34 is greater than 1, M3 does not turn off if M5 or M2 command is given!)
5. $34 = Possibility to vary the value from an M(....)S(...) command. In order to adjust and refine the resolution.

Result (already tested):

• The voltage on the IN(pwm) pin remains constant, because it does NOT consider the S 0 value as a power variation! If $34 is
  slightly higher than the desired power, it improves further!
• The laser beam will still turn on and off, using the enable pin (L pin) which will keep the same current working strategy.
• When using the M5 or M2 commands, the laser beam is switched off and made safe!
• It is also possible to refine all this using the function supported by the $34 command, extending the possibility of varying its parameters with M(....)(S....) commands.

I have already tested this type of configuration manually and using the $34 parameter...
The difference in the result on the finished product is truly abysmal!
At the moment it seems to me that no one has a custom configuration for the control of co2 lasers!
In my opinion it is fundamental since the behavior of the laser beam ignition is profoundly different from that of diode lasers!
I hope you can make these changes, because it will bring huge benefits to those who use grblHal to control their custom co2 laser!

I am available if you need to do tests or for anything about it!
Thank you in advance.
Regards

[Deltaplc]

Attached are 2 images engraved with the same parameters (speed 340mm/s power 7.6%).
Number 1 is with the current operating strategies. Number 2 is with the simulation of the operating strategy that I would like you to bring to the firmware! Currently, if I wanted to have a result similar to image 2, the only solution would be to raise the power a lot! But the result would still be terrible and not even comparable!

[Deltaplc]

Hi
I wanted to add another option....
There is a function in ligtburn "use G0 movements for overscan" that could affect the pwm output, since in laser mode M3/M4 do not work with G0 movements!!!
It is likely that if you decide to make the changes I asked you will have to take this into account!
I send you a fragment of gcode in question:
G0 X110.626Y89.399
M3
; Layer C00
G91
G0 X8.333
G1 X0.1F20000S80
G1 X0.1S0
G1 X0.2S80
G1 X0.1S0
G1 X0.1S80
G1 X0.1S0
.......
G1 X0.1S80
G1 X0.1S0
G1 X0.1S80
G1 X0.1S0
G1 X0.1S80
G1 X0.1S0
G1 X0.1S80
G0 X8.334
G0 Y-0.1
G0 X-8.334
G1 X-1
G1 X-0.1S0
G1 X-0.2S80
G1 X-0.1S0
G1 X-0.2S80
G1 X-0.1S0
G1 X-0.3S80
G1 X-0.1S0

[terjeio]

Do you have a DC or RF excited tube? And at what kind of resolution (DPI) at 340 mm/s?

If I understand your proposal you want laser on/off to be controlled by distance in G1 mode, kind of like PPI mode. If less/equal to some distance then turn laser on else turn it off?

[Deltaplc]

Hai un tubo eccitato DC o RF? E a che tipo di risoluzione (DPI) a 340 mm/s?

Hello
It's the classic glass tube with its original k40 power supply....

I did those tests at 254dpi
The picture is small....it was just to show you the difference!

[Deltaplc]

Se ho capito bene la tua proposta, vuoi che l'accensione/spegnimento del laser sia controllato dalla distanza in modalità G1, un po' come la modalità PPI . Se è inferiore/uguale a una certa distanza, allora accendi il laser, altrimenti spegnilo?

No no, it was just an addition to the main request! That is fundamental!
I just didn't know if using G0 could be harmful to achieve the CO2 laser mode as I proposed to you!

[terjeio]

You want S0 to turn off the laser while keeping the PWM output as-is?
If so it seems I have implemented the spindle code incorrectly and a simple else will correct it. That is with RPM controls spindle enable signal enabled in the settings:

Which driver are you using?

[Deltaplc]

Good morning
At the moment I'm using an Arduino Due.(SAM3X8E)
But I'm also testing a board with esp32.....

[Deltaplc]

Vuoi che S0 spenga il laser mantenendo l'uscita PWM così com'è?

Yes exactly, you should only deactivate the enable output, without modifying the PWM!

Se è così, sembra che abbia implementato il codice del mandrino in modo errato e un semplice elselo correggerà. Questo con il segnale di abilitazione del mandrino dei controlli RPM abilitato nelle impostazioni:

I tried to see if one of these options would work for me, but at the moment none of them do what I need.
There are these options: 0-1-3-5-7 ? There are no others, right?

[terjeio]

$9=3 or $9=7 is what you need - $7, And $32=0 for now. I have modified the Web Builder code so you have to flash a fresh version, if you build locally you have to change a function.
FYI M5 will currently not turn the PWM off - more changes has to be made for that.

[Deltaplc]

I cloned:
git clone --recurse-submodules https://github.com/grblHAL/SAM3X8E.git

I compiled and downloaded successfully with arduino ide...
I tried with $32=0 and $9 = 3 or $9=7...... But none of them do what I need! The pwm does not stay stable at the same level when the enable output changes to on/off.....

$7,
I don't have the $7 parameter!?
Am I doing something wrong?

[terjeio]

git clone --recurse-submodules https://github.com/grblHAL/SAM3X8E.git

I have updated the Web Builder, not github. Replace this function in driver.c if compiling locally:

static void spindleSetSpeed (spindle_ptrs_t *spindle, uint_fast16_t pwm_value)
{
#ifdef SPINDLE_PWM_CHANNEL
    if (pwm_value == spindle->context.pwm->off_value) {
        pwmEnabled = false;
        if(spindle->context.pwm->settings->flags.enable_rpm_controlled) {
            if(spindle->context.pwm->flags.cloned)
                spindle_dir(false);
            else
                spindle_off();
        } else if(spindle->context.pwm->flags.always_on) {
            if(PWM->PWM_SR & (1 << SPINDLE_PWM_CHANNEL))
                PWM->PWM_CH_NUM[SPINDLE_PWM_CHANNEL].PWM_CDTYUPD = spindle->context.pwm->off_value;
            else {
                PWM->PWM_CH_NUM[SPINDLE_PWM_CHANNEL].PWM_CDTY = spindle->context.pwm->off_value;
                REG_PWM_ENA = (1 << SPINDLE_PWM_CHANNEL);
            }
        } else
            REG_PWM_DIS = (1 << SPINDLE_PWM_CHANNEL);
    } else {
        if(PWM->PWM_SR & (1 << SPINDLE_PWM_CHANNEL))
            PWM->PWM_CH_NUM[SPINDLE_PWM_CHANNEL].PWM_CDTYUPD = pwm_value;
        else {
            if(spindle->context.pwm->flags.cloned)
                spindle_dir(true);
            else
                spindle_on();
            pwmEnabled = true;
            PWM->PWM_CH_NUM[SPINDLE_PWM_CHANNEL].PWM_CDTY = pwm_value;
            REG_PWM_ENA = (1 << SPINDLE_PWM_CHANNEL);
        }
    }
#else
    if (pwm_value == spindle->context.pwm->off_value) {
        pwmEnabled = false;
        if(spindle->context.pwm->settings->flags.enable_rpm_controlled) {
            if(spindle->context.pwm->flags.cloned)
                spindle_dir(false);
            else
                spindle_off();
        } else if(spindle->context.pwm->flags.always_on) {
            SPINDLE_PWM_TIMER.TC_RA = spindle->context.pwm->period - spindle->context.pwm->off_value;
            SPINDLE_PWM_TIMER.TC_CMR &= ~TC_CMR_CPCSTOP;
            SPINDLE_PWM_TIMER.TC_CCR = TC_CCR_CLKEN|TC_CCR_SWTRG;
        } else
            SPINDLE_PWM_TIMER.TC_CMR |= TC_CMR_CPCSTOP; // Ensure output is low, by setting timer to stop at TCC match
    } else {
        SPINDLE_PWM_TIMER.TC_RA = spindle->context.pwm->period == pwm_value ? 1 : spindle->context.pwm->period - pwm_value;
        if(!pwmEnabled) {
            if(spindle->context.pwm->flags.cloned)
                spindle_dir(true);
            else
                spindle_on();
            pwmEnabled = true;
            SPINDLE_PWM_TIMER.TC_CMR &= ~TC_CMR_CPCSTOP;
            SPINDLE_PWM_TIMER.TC_CCR = TC_CCR_CLKEN|TC_CCR_SWTRG;
        }
    }
#endif
}

I'll update github if this works as intended - after changing all the other drivers to match. And likely with further changes.

And please post comments in english, if not I will respond in burmese or something like that when I can be bothered...

[Deltaplc]

And please post comments in english, if not I will respond in burmese or something like that when I can be bothered...

Sorry!!! In my hurry I forgot to translate it!!
Now I'll try and let you know!

[Deltaplc]

I have done some field tests with my engraver.....
With:
$32=0
$9=3 / $9=7 (Nothing seems to change between the two configurations 3 or 7)
The machine keeps the pwm constant and works with the enable pin on/off as I would like!!! But the machine goes very slow and if it receives G0 commands it does not turn off the laser.

With:
$32=1
$9=3 / $9=7 (Nothing seems to change between the two configurations 3 or 7)
The machine keeps the pwm constant and works with the enable pin on/off as I would like!!! It seems to work fine with the image engraving speeds as before. And it also works fine with G0 commands by turning off the enable pin.
Even with the LB_CLUSTERS mode enabled everything seems ok.

With the new change, in any case, the $34 parameter does NOT work anymore!! Changing its value does NOT make any changes!!
As you said, the M5 command does not turn off the PWM at the end of the processing.

So, with $32=1 and $9=3 it seems to have worked!
If you can get the $34 function to work as well, that would be awesome....

[terjeio]

Replace driver.c with this version, with luck it may work:

driver.zip

There is a function in ligtburn "use G0 movements for overscan"

Overscan should be G1S0 motion with the same feedrate as engraving to ensure the PWM output does not change on the G0/G1 transition when laser mode is enabled. And the overscan distance should be large enough to let the PWM output to go to the programmed rate (at the end of acceleration).

With the new change, in any case, the $34 parameter does NOT work anymore!!

Perhaps the attached version does, if not how do you expect it should work?

[Deltaplc]

Hi
I tried to do some tests, but unfortunately I don't see any changes in the functioning, it seems to work as with the previous modification.
The $34 parameter seems NOT to work!!
Tomorrow morning I'll do more in-depth tests and let you know in more detail!!
Thank you for your support!

[terjeio]

M5 should at least work now.

The $34 parameter seems NOT to work!!

What do you expect from this setting and with which setting value?

[Deltaplc]

M5 should at least work now.
I'm sorry but I haven't been able to do thorough testing to give you detailed information...I've only bench tested. I don't want to give you incorrect information....

Yes you are right, now M5 works!

What do you expect from this setting and with which setting value?

It seems like $34 works but not in the right way....now the value $34 works at the end of the cycle after the M5 command has been received.
The pwm should load the value set by $34 every time the S0 value is read and the laser is turned off by the enable output....basically it should work as it did before the modification!

[terjeio]

The pwm should load the value set by $34 every time the S0 value is read and the laser is turned off by the enable output....basically it should work as it did before the modification!

I do not agree, at least when used with a CO2 laser power supply that needs time to settle. The PWM output should remain constant to allow a well defined leading edge. Or do you need the leading edge to have a slope? If so what about the trailing edge?
And do you know what the response time is for your power supply - e.g. from 0 to 100% PWM?

[Deltaplc]

When I did some tests on image engravings with the jarvis-dithering-etc method, not on simple engravings... I noticed that using the $34 parameter with a slightly higher power than the one set for engraving (constant) increases the definition of the image details even more!
If you manage to make the $34 work as before the modification, I will try to make two images, with and without the parameter activated, I will show them to you and then you can see the difference...

[Deltaplc]

All the modification I ask you is to be able to improve all the details in the engravings of the images (photos), for the engravings of writings or simple figures, there is no need to use the parameter $34, for this reason at the beginning I asked you about the possibility of setting it with an M parameter....
To be able to manage it more easily and also modify it via gcode...

[terjeio]

I noticed that using the $34 parameter with a slightly higher power than the one set for engraving (constant) increases the definition of the image details even more!

Ok, I see - thanks for explaining why. Using $34 to control such a feature is not a good idea - a M-code (which one?) or a new setting would be better. This is not something I can do by modifying a single file - I would have to add a core call to set a value, which IMO should be relative to the programmed S rate - a percentage? And a plugin for the M-code. And perhaps also a new $9 option should be added to enable it...

[Deltaplc]

Let's take it one step at a time, let's see that the changes we are making work and lead to improvements on the engravings!
If it's too complex to transform the $34 into an M parameter, forget it, it's not necessary!

And a plugin for the M-code. And perhaps also a new $9 option should be added to enable it...

Probably the only essential thing is to add a value to $9 (or some other parameter) to activate and deactivate the configuration we are creating, because not everyone needs it....
I am always available for all the tests you need!!

[Deltaplc]

which IMO should be relative to the programmed S rate - a percentage?

If I understand what you mean, I had thought about it too.... create a parameter similar to $34 that takes the S value of the engraving + $xxx as a reference.
Example: engraving value (constant pwm) S80 + $(new $34) = 5% result: when the S0 command arrives the pwm rises and takes the value 84....
This would make this engraving strategy much easier, because you would no longer need to manually raise the $34 value based on the power set for image engraving!

[Deltaplc]

Good morning
I downloaded the new modification on my engraver...
I did some quick tests, image and simple engravings (on poplar wood with borax).
I used various speeds and various powers.As you can see the result seems good, no problems with entry and exit ramps.The engravings are well detailed on the edges!
I attach an image so that you can also evaluate the result....

I used $32 =1(laser mode)
$9=3 (I also tried $9=7 but I don't see any difference)
I engraved with $34=0 because even if I set it to other values, it doesn't work during engraving at the moment and therefore it is not useful for the strategy....
Yes, now M5 or M2 at the end of the engraving bring the pwm to zero....
If $34 is greater than zero, M5 or M2 DO NOT turn off the PWM at the end of the process....
In my opinion in laser mode ($32=1) you could also bring the output controlled by M4 to zero....(it is not essential).

If you need further feedback or information, I am available!!

[Deltaplc]

[terjeio]

As you can see the result seems good, no problems with entry and exit ramps.

This means there is no need for a new M-code?

[Deltaplc]

There is a problem with the new modification!!
Continuing to do some tests, it seems that the enable output does not activate until inside the engraving it is given an S0 for the first time!!
I'll give you an example: engraving of Hello, it starts to engrave the letter H and does not engrave it, then it moves on to all the others and engraves them all correctly!!
I didn't notice before because I had only made "full" incisions, and not a simple circle perimeter incision or cut!

[Deltaplc]

This means there is no need for a new M-code?

Se riesci a fare un parametro $ (Simele a $34) che si muove dinamicamente in relazione alla potenza S di incisione, probabilmente il comando M potrebbe non servire!

[terjeio]

Continuing to do some tests, it seems that the enable output does not activate until inside the engraving it is given an S0 for the first time!!

gcode please, at least the initial lines up to the first expected laser on.

If $34 is greater than zero, M5 or M2 DO NOT turn off the PWM at the end of the process....

Correct - same as the behaviour from the LPC version of Grbl that has the $34 - 35 settings. 8-bit Grbl does not have them.

[Deltaplc]

Sorry, but I would like to give you more detailed information, to help you understand how to solve the problem...
Resetting the board, the problem disappears, at the first engravings.... It seems that it is triggered between a single engraving and the other!
I try to explain:
If I engrave the first time after the reset, everything is ok... if I make other engravings, the problem I described before occurs! The problem remains until I reset the board!

[terjeio]

Now switched to M129 to enable overdrive.

[Deltaplc]

Ora sono passato a M129 per abilitare l'overdrive.

Good morning
Ok, that's great!
Have you already inserted it in the plugins on all cors? Can it already be downloaded by everyone, even for manual compilation?

In these days I had the opportunity to do a lot of tests with the new plugin!
I have not found any negative aspects!!
No bugs!
It has improved in all aspects the behavior of my engraver! Photo engravings, written engravings and also on the cut!! No type of exit and entry ramp on full engravings!
Fantastic!
Again, many thanks for your work and your support!!

[Deltaplc]

Now switched to M129 to enable overdrive.

I sent you a message, because it did not accept the command and gave me:

M129P30
error:20
Unsupported or invalid g-code command found in block.

Sorry but I had to reset the board several times, and remove power for it to accept the M129 command.....
Now it seems to work!!!

[distebia]

I can't send m129p30, I generated from updated web build, where am I wrong?

[Deltaplc]

Non riesco a inviare m129p30, l'ho generato dalla build web aggiornata, dove sbaglio?

Does it give you error 20?
Try resetting the board several times, and maybe even removing power. It did the same to me right after downloading the firmware...

[distebia]

error 20...can't send m129 and can't find parameter $709, if I remember correctly. even resetting and restarting doesn't change anything

[Deltaplc]

error 20...can't send m129 and can't find parameter $709, if I remember correctly. even resetting and restarting doesn't change anything

Are you sure you have successfully compiled and uploaded the firmware? Make a $I and share the report!!

[distebia]

[Deltaplc]

I can't seem to see :[PLUGIN:CO2 laser overdrive v0.01]!!!
For the rest I'll leave the floor to Terjeio...
He will surely be able to help you!

[distebia]

I generated from web build, now I understood that I had to compile locally...but is the modification already available for all drivers?

[terjeio]

M129P30
error:20
Unsupported or invalid g-code command found in block.

I have added trapping of settings changes in todays commit so changing these ($39 and $9) will instantly make M129 available/unavailable.

The Web Builder has been updated to support the new plugin, check CO2 laser overdrive in the Plugin tab.

but is the modification already available for all drivers?

For most, all supported by the Web Builder. There are a few (one?) boards that gates the PWM signal electronically - these will not work. Some has isolated PWM output via slow optocouplers, these may also be a bit problematic... And ensure the PWM frequency is high enough if doing high speed engraving.

$709 is only available when the driver and board supports two PWM spindles, and the second is enabled. Very few boards do.

[distebia]

I used web build for the firmware with your latest modification, loaded the firmware, I see the plugin active but m129 is not accepted, both by changing $39 and $9=1, 3 and 7

settings.txt

[Deltaplc]

In my case $32=1 $9=3 works fine!
For M129P(...) You have to reset the aboard after downloading, unplug the board (usb) and reconnect.....In my case, this procedure worked every time I compiled and downloaded the firmware...

[distebia]

done + times, the plugin is present but I don't have the m129 commands...$32=1, $9=3, but $39 how should it be? mine is a normal co2 40w but with a teensy board, how do you keep the other parameters $32 etc.. for the laser?

[distebia]

I was doing a test with the new firmware, even without m129 parameters... I notice that the laser does not turn off during overscanning and creates an external frame, as in the photo

[Deltaplc]

$39=1
With this plugin the pwm always remains constant....the enable pin turns the laser on and off!!
I have no problem during overscan....
These are some tests...!
Image

[distebia]

congratulations for the photos...and how do you set the values ​​33, 34, 35 and 36? and the m129 command?

[Deltaplc]

values ​​33, 34, 35 and 36?

default settings

and the m129 command?

Based on your engraver's response needs

[distebia]

i miei valori sono $33=20000, $34=0, $35=7 e $36=100, il tuo 34 lo lasci a 0 e alzi solo da m129?

[Deltaplc]

il tuo 34 lo lasci a 0 e alzi solo da m129?

Yes, exactly.

i miei valori sono $33=20000, $34=0, $35=7 e $36=100,

In my case $35=0
These are all values ​​that can vary from engraver to engraver! You will have to do some tests to see which configuration will work best for you!

[distebia]

se faccio un cerchio con il valore $35=0 non viene chiuso, devo alzare a 7 per avere il cerchio chiuso...grazie per i consigli...

[terjeio]

I notice that the laser does not turn off during overscanning and creates an external frame, as in the photo

Be aware that some boards has open collector/open drain outputs for PWM and/or spindle on. If not properly loaded these may exhibit rather low slew rates that can affect high speed engraving.

[distebia]

this happens to me both on mks dlc32 and on teensy 4.1 (with grblhal) but if I put fluidnc on mks dlc32 it doesn't happen

[distebia]

$39=1 Con questo plugin il PWM rimane sempre costante... il pin di abilitazione accende e spegne il laser!! Non ho problemi durante l'overscan... Ecco alcuni test...! Immagine

tests and tests but nothing to do, the laser with the values ​​$9=3, $32=1, $39=1, $34=0, $35=0 and m129p10 always remains active and the ammeter reads 5mA... Maybe I understood why... from mks or teensy I command the laser only with the pwm pin (which in our configuration always remains active) .. what should be the enable pin and how to rewire for the k40? do I have to act on the co2 power supply on the TL pin? @Deltaplc

[Deltaplc]

This is the essence of this plugin!!!!
Constant PWM, laser on/off through the Enable pin!!!
If you do not connect the laser power supply correctly, with both pins working, this plugin will not work!!!
The correct way to control the power supply is described by the manufacturer!!! You do not have to follow diagrams found online created by who knows who!!!

Pin IN= pwm
Pin L = Enable

@distebia Tu sei italiano,giusto?

[Deltaplc]

A tip....
Pay attention to the compatibility of the voltages between your board and the laser power supply!
In my case with an Arduino Due (3.3v), to be safe I made the coupling via an optocoupler made specifically for this job.

[distebia]

Yes, Italian..in all the co2 lasers I have built I have always adopted this system: WP closes to G passing through thermostat and flow meter and TL brought to G by a simple switch, like to give a manual ok. The pin on teensy (or mks) has always been the PWM pin that I bring to IN on co2 power supply. I understood the modification to make but I suppose I have an enable output of 0-5v, I don't know if I can invert it, if it goes badly I connect it to TH on co2 power supply? what I don't understand now is how to generate the firmware, which PWM do I have to select? and if I compile locally how to activate this modification?

questo è il mio alimentatore

[Deltaplc]

I don't know, I use arduino due.....
You need to see the pin map file...
I'm sure @terjeio can help you better than me....

TH

Yes, those two pins are used to control on/off, depending on whether you have low or high logic.

in all the co2 lasers I have built I have always adopted this system: WP closes to G passing through thermostat and flow meter and TL brought to G by a simple switch, like to give a manual ok.

In my opinion...a profoundly flawed connection logic!

[distebia]

I have never used the spindle enable pin, I control everything by pwm, s0 off