Getting the PID... What's left

I’ve decide I’m jumping to get the PID DEVELOPMENT KIT because even a spindle with a power supply is turning out to be at least $175. I was curious what else is left to be developed since from what I can tell everything is finished. I message Ryan and he said that he really just need to pick a screen/controller and most of the LCD stuff is there.


@vicious1, can you clarify what you mean when you just need to pick a screen/controller? Do you ramps vs Rambo or something else? I have RAMPS, so let me know if I need to look into the rambo. Another question I had was which pins do the PID use. I saw in another post you said that they use the same pins I would want to use for my laser. Would it be easy to make it so I could use both with out a lot of switching things back and fourth? I’ll do it if I must but having them both ready to go would be ideal.


I’m so excited for all the thing I’m going to mill with this. I’ll wait patiently for your answer. Thanks for all the awesome stuff you are doing.


The PID runs on another arduino. The nano. The speed is set from Marlin, and that’s “communicated” to the nano with the PWM signal. It’s the same pin on the marlin that sets the laser power. This is the only pin you’ll have to change to switch between the laser and PID. It’s a simple 0-5V signal, so a two way switch can easy change between them.

For the screen, there are two parts. The first is that the screen needs to be picked and connected to the nano. The second part is to write the code for the nano to also talk to the screen. The screen isn’t strictly necessary, but we’re thinking it will add a lot of insight into what the nano is doing and adding some configuration like antichatter. How that stuff gets displayed, how the choices are made and the actual interface code needs to be written and tested.

We use a spin up delay for the spindle that you would not want on a laser. There is a chance of using another pin but I don’t know off hand. A firmware flash isn’t that bad of a process but better not to have to.


Yup. It works as is, through the gcode, a screen is a bonus. Anti-chatter…cherry on the cake.

Does the PID need a 12v or 5v signal? I saw @dkj4linux had remapped a pin for their laser. I hope this reaches them if it doesn’t I’ll message them directly to find out how they did it.

Do you know the overall requirements of the pin for the PID kit?

5v, we picked pins in that thread. If you have a ramps it is the same as the laser pin from the $100 leo laser. A servo pin 44 I think.

I was talking with someone at Endurance laser since I wanted to use their 10w laser but if I switch pins I’ll need to get an additional power supply and a few other extra parts. Does the PID require D9 or could I change the pin that is uses instead? If I have to get the extra parts I will but I’d like to try an reduce the size of the enclosure keep the electronics away from other users.


Thanks for all the help. I’ll post pictures of the final project when I’m done.

Even if it’s not 5v you shod be able to buck it up. Signal doesn’t move many amps.

I did some reading and found out how to change the D9 pin to another pin on the board but I’m not sure if that is going to solve my problems since I would like the PID controller and the laser to use different pins. Might you be able to help me find the sections within marlin that related to the PID controller and lasers?


After looking at the marlin website, they seem to lump spindle control with laser control. This starting to make me think that some kind of signal switcher might be the easier route. If any one who has experience with marlin can let me know if I can separate the two feature that would be greatly appreciated.

Since the above option of splitting the two feature out from each other doesn’t seem likely, do I just need a switch that would allow me to set which wires the signal goes down or am I simplifying this too much. Would trying to create my own M code that had the hardware set the path of the signal be too hard of a task to accomplish?


Sorry for being all over the placed and delayed with my responses. I’ve been too busy at work. Thanks in advance for any and all help offered.




When you say buck it up, what are you talking about exactly?

These are great for controlling 12V PWM from a 5V PWM signal:

They make two versions. One will pull the output to ground and one will pull it up to 12V. I use them a lot for controlling 12V LEDs in projects.

So if your laser needs a 12V PWM signal to control it, you could switch between the PID input and the input to the ULN2801, and the output of the 2801 would be the controlling pin for the laser.

I highly doubt there is a simple software fix. You could ask on the Marlin github. They seem to be looking for new features.

Does this work only if the laser requires a 5v signal? Also were you saying that chip would take the place of a switch?

If the laser needs a 5V signal, then you just use a switch. If the laser needs 12V signal, then you use a switch, and then convert the signal to 12V, just for the laser.