If it occurred twice with 2 boards that would indicate there is some fault with your hardware. Problem happens when you are trying to print, so lets narrow it down to heaters.

@dc42 Never connect the input of a DC-DC converter to a heater or fan output. - I did exactly that, what might be consequences?

I will follow your advice, thanks for letting me know.

I guess I got lucky, 1st rule of engineering: If it ain't broke, don't fix it

Yes S1 and S0 works for me but Led it too bright I needed to dim it.

Anyways got this issue solved, I added step down DC converter between Duet and Led, now flickering is gone.

@bearer I tried all sorts of PWM values, I don't really need to dim them but I have to be able to turn it on and off with G-code commands. And I don't have any driver after duet, just a resistor

@taconite I cannot have this LED always on, I need to be able to switch in on and off with m106 commands.

I'm using duet wifi to build pick and place machine with bottom vision camera and led ring around it.

I have problem with horizontal lines on camera image and I suspect it might be caused by Led controlled by PWM from Fan2 output.

Is there any way to switch off PWM on fan and just have plain voltage control instead?

Thanks
Arkadiusz

@Veti I just printed calibration cube and it came out 3.5mm too short, missing bottom layers.
Z axis doesn't work until it reaches offset height I setup on E1: G10 P1 X0 Y0 Z3.5 U0

edit:
I removed offset from G10 command and instead in Cura in extruder2 start g-code I added:
G1 Z3.5
G92 Z0
This did the trick, now I have to find way to implement it in duet config file. It works fine but I prefer to not rely on Cura to execute this command.

You're right, adjusting offset on E1 doesn't mess printer in the way E0 does.
I swapped connections between E0 and E1 and it works fine now thanks.

Its very weird that E0 does this, I took me a while to figure out it was Z offset on E0 causing that.

Hi,

I have dual extruder setup where one of them is lifting up when second extruder is used.

So E0 is low and moves up when E1 is used by moving U axis, therefore there need to be 3.5mm offset on Z axis for E0

I tried to implement Z offset in config.g using G10 P0 X0 Y0 Z3.5 U0 - it worked for offset but messed my printer and it Z axis wouldn't move during print anymore, printing only using X and Y axis.

Is there any other way I can implement this offset? I'm very basic with gcode.

Pcb breakout board for stepper driver arrived, this solved my issue.