Before I create a Smoothie config page for the documentation,

Before I create a Smoothie config page for the documentation, is there a preferred method of control ie the one wire or 2 wire method of PWM. +Peter van der Walt or any of the other devs? Or should I document both ways?

1 wire 1 wire 1 wire as you will find out soon enough. Best performance when we leave the pot in play.

Just don’t smoke the pot :slight_smile:

OK,will do a 1 wire config.

Easy to do, I have a C3d board now. I can also do a config for grbl using an uno with cnc shield.

OK, the world has conspired to stop me from posting on the doc site…I seem to have lost all access. What the hey is going on???

I will just write it up and email it to Carl, he can post it.

@funinthefalls ​​ Yes, the evil Internet electrons are aganst you. Uh!

OK, so in the one wire setup, how are you connecting it. On mine I took 2.4 and it runs through a level shifter, then to the L input on the PSU. Is this how everyone else is doing it?

@funinthefalls If you’re doing that, then in the smoothie config, you have something like “Laser_module_ttl_pin 2.5!” right? Just as correct is use the level shifter and connect to TH and then the config would be “Laser_module_ttl_pin 2.5”. Personally, I think I’ll just use a pull up and open collector on PWM, with “laser_module_pwm_pin 2.5o”

There are so many variations on even just the 1 wire setup, am not sure what the best practice method would be. Maybe the devs could weigh in here, @cprezzi @Todd_Fleming +Peter van der Walt Jorge Robles

L from the PSU to a hardware capable pwm pin mosfet like 2.4 or 2.5. C3D Mini uses 2.5

I use the open-collector transistor output on 2.4. No resistors needed. Don’t invert with !.

Do you use a level shifter @raykholo ?

Not for L. And our recommendation now is to keep the pot, in play and run L to the 2.5 MOSFET. Done deal.
If you’re doing this with the C3D board it’s already taken care of as such.

@Todd_Fleming ummm. So you run from 2.4 to the PWM on your laser driver? No pull up resistor. You don’t have it bridged to 5V, do you? (I’m wondering if your laser driver has a built in pull up?)

The L on the k40 psu is the - of the LED of an opto. You connect to ground to fire. Hence no level shifting for L.

@funinthefalls I think you should cover 3 bases.

  • 1-wire into either TL or TH, it doesn’t matter which one.
  • 1-wire with manually variable power level using a potentiometer.
  • 2-wire with PWM. I’d write it up with using a level shifter since that one should be the most straightforward of all the 3.3V-to-5V solutions.

@raykholo are you using the power level signal too?

@Richard_Betel I simply hook up L to a mosfet. I leave the pot in play. Well I used to have a level shifted pwm signal going to replace the pot but a bunch of my Cohesion3D Mini customers that were doing this upgrade had less than stellar results with that way. So again, I recommend, keep pot in play. Hook up L to a mosfet. Be done.