Adding laser to 6 lackwhat addon card do I need an

Anyone know what I need to run laser with 6 pack. I have external drivers that’s it. What cards do I need for the board.

What specific board do you have? Are you talking about Bart Dring card?

What specific laser module are you considering?

What firmware are you running?

Bart’s 6 pack, grbl firmware fluidnc
I haven’t bought laser yet.

You need a 5V out for laser PWM. This is easiest solution if you don’t already have one:

You can also DIY an expansion module with some 5V outputs, but most folks would find it’s not worth the effort… especially considering how much Bart is asking for the boards.

Another alternative… the 6-pack has that Vcc jumper to select 3.3/5V for the drivers and i2s chips. Since you’re using external drivers, you likely already need 5V. Since this setting also makes the i2s pins output 5V, you could directly tap into one of them with male dupont connectors. The downside with this method (it’s a big one) is your i2s pin is not buffered. So it won’t be protected from reverse polarity or other common mistakes, that could brick the expensive 6-pack. That risk is mitigated using a real expansion modules.

Regardless if you use Bart’s PCB, make your own, or use the direct to i2s hack, you will have to edit your config.yaml to add a laser section with the pwm pinout definition. Pinouts for the latest 6-pack can be used to pick a pin for use in your config.yaml (cnc io module pins are on the bottom):

Note if you have a v5 or older 6-pack, the 12 pin connector with gpio28-31 will be missing (that’s a new feature).

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