Thanks for the tip Alex. I just play around basically stuff for grand kids etc. Nothing up to your level. Still learning just a hobby.
I can go “rays dreaded” level shifter route and try pin 1.23 tonight 
. Last night I tried 2.5 but I couldn’t get it to fire. I turned the pot all the way up and I got a very low laser fire.
If you have a pulse stream going to the L pin as seen on the scope moving to a level shifter is not going to help. If you have a pulse on L something else is wrong.
Can you post a picture of what you see on the scope on L. BTW the fact that you can see an image when the pot is turned up suggest PWM is working and something else is overriding it.
Some things to consider is voltage levels and the polarity of the PWM signal.
If you can post config file, wiring of both ends of the PWM wire and scope pictures we can make this work.
One more time … level shifters may work but they are a poor design choice (for many reasons explained on my blog) and they are just more parts that degrade not gain control of your LPS.
Many many K40 machines are running single wire open drain configs successfully.
Cheers
Hi Don, I appreciate your response and I’ll post the config file when I get home tonight but I did want to mention that the signal I was looking at did not look like PWM. It was on or off. I did not see any type of square wave. I should also mention that I was using an old analog scope. I have a pretty nice digital one I’ll be working with tonight. Hopefully I’ll be able to post some good images. Until then I’ll stay away from the level shifter.
One thing I noticed in my config is that it appears that I have 2 functions assigned to the pin I’m using. In the laser section I have pin 2.6 defined. Further down in my config file I saw that switch.fan.output_pin is also 2.6. Perhaps this is my problem?
Ok, here are some scope images. Remember that I’m not exactly an expert with these things but… images at 1%, 50% and 100% power. Looks like a good signal from pin 2.4. I’ll post my config file next.
This is my wiring. I don’t think I added the endstops. All the images are from the web.
Update: changed the pot and have variable Pwm signals. I noticed that a percentage lower than 30ish won’t leave a mark during testing. Are there parameters I should stay between when engraving in laserdraw?
@Chuck_Comito these scope signal look good to me.
Does your update say that now it is working?
Are the scope traces before or after the pot change?
The pot was bad?
In the middle of this did you fix the duplicate 2.4 pin assignment I see in your config file?
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The power out will be a combination of pot and pwm settings. So that if you set the PWM at 10% and the pot 30% the power will be 3%.
If your max current was 25 ma then the actual current might be .75 ma which will not likely fire the laser or make a mark.
What do you mean engraving in Laserdraw do you mean Laserweb 
Hi Don, my update says that the PWM is working. The pot was bad for sure. I’ve replaced it with a 10 turn, 10k pot (all I had). I did not fix the duplicate 2.4 pin as I didn’t see it but will do so now. That said, with the pot all the way up, laserweb will not output anything less than 30%. With the pop all the way up the power should be somewhat relative to the software settings (I think?). And yes, I meant LaserWeb.
I have laser_module_pin set to 2.4 and I have switch.laserfire.output_pin set to 2.4^. These two lines confuse me. Which do I need or should be using?
You only need the laser_module_pin set to 2.4. Don’t assign 2.4 anywhere else.
Almost ready to run some tests. I’ll report back. Thanks Don!