Cannot seem to get PWM control.

@donkjr

Im still running ground with the 24v in on VBB, correct?

@Jerry_Hartmann yes the 24V and grnd does not change, this is just the PWM and its signal ground. Did you verify with a DVM that the black wire is grnd ?

You now have to insure that your config file is right and on the SD card.

@donkjr laser module pin was already 2.4 while using the leveler. Do you mean switch.laserfire.output_pin ?

Ok, so neat, it fires without the leveller. I copied your config onto the sd and it will attempt to engrave but it still does so at max power

@Jerry_Hartmann you only need one port P2.4, I I have laser-fire disabled.
Can you provide a picture of what you are engraving. Best to use a grey shade test pattern.

@donkjr That should be 50% grey

@Jerry_Hartmann Pictur above barely visible. Suggest trying a grey scale pattern as its hard to see changes with a single power level.
You still have the current pot installed right?
Turn it down until the engraving is just visible and make adjustments to it and lower speed to tweak it in.

@donkjr I cant turn it lower than 5 or it wont fire. Even at 5 its still digging in deep.

@Jerry_Hartmann lets try it with a grey shade pattern…then post picture and we will start from there.

  1. What CNC software (didn’t see in your profile) are you driving this with. I.e what is creating Gcode?
  2. Have you tried changing the speed and what are you running?
  1. Yes
  2. Laserweb4

@donkjr ​ greyscale produces no change

@donkjr Any other suggestions?

@Jerry_Hartmann did a miss a picture of the grey shade pattern?

  1. Can you cut?
  2. Can you see engraving information but it all one shade?

What was the answer to #2 above?
A picture of the grey shade pattern would help.

@donkjr#2 was answered above. I can cut just fine.

I wont have pictures to upload until tonight

@Jerry_Hartmann also insure that your PWM period is set to 200 not 20? What is it set to now?

NP I will check back in tonight on the pictures.

Its a common problem to have engraving issues when first setting up. These things have to be correct:
A. Pot tweaked to the minimum power to get darkest area.
B. PWM period tweaked to 200-400
C. Speed tweaked, may need to speed up to engrave properly.

@donkjr ​ I used the config file you provided

@Jerry_Hartmann yes I know.
Assuming that PWM is working correctly, these machines need tweaking to get the best results. My machine is currently optimized for cutting.

Change the PWM period from 20 to 200, then 400 and try engraving both configs.
Note: some machines cut better with 20 but engrave better with 400. I can explain why but its a long story :)!.
Your best engraving is a combination of A-C above.

@donkjr That did it! It engraves at both 200 and 400. A weird quirk though is that if I set the dial to 15mA and tell it to use 40% power, the result is still rather dark but i can control that with the dial.

I’m super stoked!
Thanks so much!

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