GRBL-LPC on Smoothieboard X0 "No supported firmware" problem

Hi all, I’ve got exactly the same problem : Unable to have GRBL-LPC running fine on an original X0 Smoothieboard. When I flash the GRBL, i’ve got nothing or code 3 error, but I can flash the smoothie firmware and it works fine. I tested it with an other SD card, same result. But with an other smoothieboard (with 3 axis and no Ethernet) everything works fine (GRBL-LPC and smoothieware).
I remember that I have test several things on the first smoothieBoard (using jog fimrware version), but it was a while, and I probably updated the bootloader.
I’ll try to put the last bootloader on the smoothie when I could (maybe next week).

Does the X0 still have the I2C stepper current control chip? If not, this could be the reason.

There is a lot of unpopulated pad on the board as you can see here :
I guess there is no crurent control.

Ok I see, the I2C digital potentiometer chips are not populated. This may be the reason why the smoothie grbl-LPC firmware is not booting.

To find out if this is the reason, you can try to install the firmware for Cohesion3d Remix board, which has no digital pot chip (but also slightly different pin mapping). If this firmware starts, we know it is the digital pot.