First of all, please excuse me for my bad English I use google translation.

Here I have a cnc laser and I want to use it without pc.
I saw on the net the beginnings of projects with two arduinos,
1 grbl and 2 gcode in TX RX. After 2 days of research with my english
more than approximate I despair of finding a successful project
of arduino grbl without pc. So if by the greatest of luck you had
a link I tell you more than a big thank you.

I don't understand why you have I2C in your title?

As far as I know you can run GRBL with a GCode file on an SDCard - Google GRBL SDCard

You could also have one Arduino with an SDCard attachment send the data using a serial link to the GEbl Arduino.


ok thank you but I see a little too hard for me.
so I'll probably use a mega arduino with marlin.

thank you

so I’ll probably use a mega arduino with marlin.

I have not used GRBL but I doubt if it is any more difficult than Marlin.


Here I have a cnc laser and I want to use it without pc.

It would be best to say what you DO want to do , rather than what you don't want to do.

GRBL should be fine to run the laser ( cutter ? ) what you need to explain is how you want to send the GCODE to the arduino running GRBL. You will need some kind of GCODE sender prog on a USB. If you don't want to use a PC, what do you want to use?

There are details on keeping track of what is sent and received because there is no real handshaking on serial over USB, so when GRBL buffer is full you need to know when to stop sending.

GRBL project on github explains exactly what you need to do.

If you are not using a PC , where is GCODE generated and how do you want to store it and send it to the ( presumably ) arduino acting as the GCODE interpreter and controlling the motors?

Hope that helps.