Laser Output

[Macwolf]

Hello, I have a Duet 3 XD and the "Laser, VFD..." connection is a mystery to me. How is this pin addressed? Is it an "OUT"? Unfortunately, it is not mentioned anywhere in the documentation.
Thanks

[jay_s_uk]

@Macwolf you can use laser or vfd as shown in the source here https://github.com/Duet3D/RepRapFirmware/blob/f6e475196704a19df10149f61dde4d5a2d6b5e81/src/Config/Pins_Duet3_MB6XD.h#L206

[T3P3Tony]

@Macwolf (and anyone else reading this later)

It's in the documentation here:

https://docs.duet3d.com/en/Duet3D_hardware/Duet_3_family/Duet_3_Mainboard_6XD_Hardware_Overview

In the "Pin Names" section.

[Macwolf]

@T3P3Tony many Thanks is OUT 6 in the documentation

[Macwolf]

@jay_s_uk Thanks, I didn't know that this source explained it.

[jay_s_uk]

@Macwolf @T3P3Tony I don't think Out6 and the VFD/Laser pin is the same. The source indicates they are different, in which case the pin names section is incorrect. This may be a carry over from the 6HC which shares the VFD output with out6

[T3P3Tony]

@jay_s_uk thanks, that is a good spot! You are right, its on its own pin on the 6XD.

@Macwolf using "vfd" is correct.

@droftarts - docs updated.

[Macwolf]

the Duet board is configured, I use a CO2 tube. A "tool" is configured, see Config, but there is a problem, when I start up the machine, the laser is active!!!
I use the active high input on the laser power supply.
Markus
config.g

[jay_s_uk]

@Macwolf you may need to invert your signal.
When i ran a K40 laser (CO2 tube as well), i used the negative side of a hotend output

[Macwolf]

@jay_s_uk
M452 C"! Laser" R255 Q500;
no change. or how to use the negative output

[jay_s_uk]

@Macwolf try wiring the laser fire pin to the negative of out0, 1 or 2 and change your config accordingly.
you can see more detailed wiring for the K40 here https://github.com/TeamGloomy/LPC-STM32-RRFUserConfigs/tree/master/K40 CO2 Laser - SKR 2 - ESP - paulg4h to see if that marries up with your machine

[Macwolf]

@jay_s_uk
A technical question: How much frequency does a 40W CO2 laser tube need? In your example, is the Q value 5000? Or does that not matter.
I am new to this area and am wondering whether I am implementing it technically correctly. There were no operating instructions included, neither with the power supply nor with the tube.

Markus

[jay_s_uk]

@Macwolf IIRC, the 5KHz came from previously available information from when people were converting the K40 away from the original controller to boards that use GRBL etc

[Macwolf]

@jay_s_uk
Out 1 is now the output for the laser, it doesn't deliver a negative signal, does it?

further connections are needed.

1. 5V for TH

2. ground

3. I simulate the cooling.

where exactly should I connect these cables to the power supply terminal

[dc42]

@Macwolf said in Laser Output:

Out 1 is now the output for the laser, it doesn't deliver a negative signal, does it?

OUT1 is an open-drain output, suitable for connecting to an active low input with internal pullup on the laser module.

The output on the VFD/Laser connector is active high, suitable for connecting to an active high input on the laser module. It should be low when the Duet is powered on. However, when no power is supplied to the Duet you may find that it floats high enough to trigger the laser. if that happens then try connecting a 1K pulldown resistor between the output and ground.

What type of control input does your laser module have?