Setting up Remora for laser cutting

In my config I have the freq for the pwm set to 0 and that turns it into a pdm signal pulse density modulation.
If you change that to a actual frequency you may see it change.

But there is a quark of running pwm on the servo thread. As the servo thread is slower than base. Someone with more info would need to chime in

Well the freq only matters when you are driving a remora output. For the remora pwm config version you just need to feed it a value of 1to100
That's why the dac plus scale works if you look at the value in Hal viewer and look at the signal as you increase the speed the value should go up.

seting the freq to 200 and then setting "net spindle-speed-scale spindle.0.speed-out => remora.SP.0"
got it firing. it goes from a value of 1 to 101 with one push of the "+" button but that's probably the scaling stuff going on.
I need to map S0-S1000 in gcode to 0-100 for remora.SP.0

Maybe spindle.0.speed is already defined... I will start probing the halmeter to see what's moving without any of the things you added for your closed loop VFD driven spindle. Fumbling my way there with your help. Thanks.

And I just figured out that the M3,M4,M5 commands are wired to the spindle.0.speed-out directly.
ie speed.0..speed-out = X when X is set by SX

Currently it seems to be effecting the frequency too because I see the LED pulsing different frequencies when I increase S. I need it to be fixed at some freq between 200-400, like 300 Hz. It would be best to use the remora pwm if I can get it to work that way.

a single line in my basic hal file gets things working somwhat.
net spindle-SP spindle.0.speed-out => remora.SP.0

But a put a real O'scope on the output pin and the frequency varies with the PWM value sent to remora.SP.0 when I believe I need a fixed 200-400Hz PWM frequency. Once I can get that, then I can work on mapping S0-1000 integer to a PWM of 0-100 float.

simple file for you to test.
to set power use the following
m3 s1000
This will set your power to 100%

m3 s100
This will set your power to 10%

To check the value you are sending to remora select machine from the top then select show hal config
select the watch tab on the right
then on the left side select "pins" then select "abs" then select "0" and finally click "out"

then as you enter the above m3 s# commands you will see this value change. remora pwm needs a value of 0-100

to manually enter g codes use the mdi tab in axis

I'll have a look. I've been using Hal Meter to show one value at a time. That's where I started looking at things and saw spindle.0.speed was responding to the M3,M4,M5 and Sxxx gcode.

you will love the show hal config then
in the watch tab anything you select can be seen.
and there is an option to save your selection so you can just load it back up.

it was a god send when i was working with the pid system.

in the file dont worry about the whole calling it a DAC 0-10v control
this is just a simple scale to give remora a value for its pwm generator.

For me i used it to turn on and off the heated bed transistor that was being fed 10V so i was getting a 0-10V pwm controlled output.
I then took that and ran it into a low pass filter just a few resistors and a cap to turn it into a analog signal of 0-10v for my VFD drive.
But at the end of the day it still just pwm with extra steps.

Thanks for pointing out the hal config watch feature, it's way better than looking at one thing at a time with Hal Meter. Scott had mentioned Hal Config but I'd only used it the once and didn't recall how to get there again.

Yes, the sample hal file works sorta and scaling by .1 does do the div/10 needed to map 0-1000 to 0-100. After setting the output pin number from 3 to 0 it will fire the laser but the frequency is not fixed and it causes problems. At low spindle speed settings(S100) that put the Laser Power Supply(LPS) into oscillations which eventually locks up the controller.

The Remora PWM is operating in PDM mode... I tried RCSERVO on that pin but it didn't seem to work.
I need to see if there is a way to set the frequency of the PWM instead of having it vary with pulse width settings.
If not, then I'll be forced to bit bang a GPIO. I just checked my Smoothieware config.txt file and the base PWM frequency was 5KHz( 200uS ).

how are you driving the laser?
i would hope you are not just turning on and off the entire power supply.

if you are trying to control a laser by turning on and off the entire driver you will run into problems.

i hope your drive has a ttl input for logic or direct pwm input.

I have worked with lasers in the past and can tell you many drivers dont like to be turned on and off via pwm.

if you are having issues with the remora pwm gen i would say to skip it for now.
Just have remora give you a normal output pin and then have linux cnc make the PWM signal.

I asked the creator about the ability to set freq of the pwm in his github but im not sure if its going to be worked on yet i think the tmc driver are still being done.

some reading in regards to pwm scroll down and you will find it
linuxcnc.org/docs/2.8/html/hal/rtcomps.html

then take one of the files i uploaded the used linux cnc for the pwm gen and change
setp pwmgen.0.pwm-freq 0 to setp pwmgen.0.pwm-freq 400

This will turn on and off the normal output pin on your 3d printer main board as normal pwm.

It's a K40 laser and there is a TTL input on the Laser Power Supply(LPS) for PWM to adjust. People have been upgrading the laser with Smoothie boards for years doing PWM into the LPS.

The MKS Sbase v1.3 board in my machine has been running Smoothieware for years so all I've done to get LinuxCNC controlling it is put Remora firmware on the MKS and have been working through the spindle side of things as that is how all the GCode based controllers do laser power adjustments.