RAMPS board pins vs GRBL board pins

I just got a RAMPS board, and loaded Marlin on the Arduino.

I want to do Laser. Can I switch to GRBL code and (LaserGRBL)? I know the RAMPS is bipolar and the GRBL has (drives) UNIPOLAR. but at the Arduino drive level, the pins could be the same, or maybe a header file can be configured on the GRBL build?

Thanks,
Alan

[reprap.org]

Steppers are identical apart from having a centre tap each coil... which can just be ignored.

Marlin speaks a different gcode best to put GRBL firmware on it...

Several people have ported GRBL to ramps... eg [sourceforge.net]

That's true, but if they SAY unipolar, I'd think they mean to drive it using a center tap. Most of my bipolar steppers have 4-wires. Not so much about the steppers, but I was wondering about the pins used by the boards.

I did find a GRBL_RAMPS1.4, so looks possible...

Thanks.

I dont know where you are seeing this..

I see lots of pleas for UNIPOLAR support and some user saying they have hacked it in...

Every GRBL board Ive ever seem just uses standard a1488 drivers or EasyDriver or TI DRV8811 all of which are bipolar

For the RAMPS it comes down to : step, dir, enable.
It doesn't know, what kind of stepper (driver ) it controls. If there is a unipolar driver that suits the pololu-pinout, go ahead and use these 5-wired steppers.

I can't find the board now.
That's probably where I got it, from somebody wanting to drive unipolar stepper motors. Although I have several old unipolar steppers (from old disk drives), I don't want to use them!

So do all these board designs tend to use the same processor pins to drive the stepper modules; control heatbed, extruder and fan, as well as limit switch and temp sensor inputs? Between RAMPS and GRBL boards? That's basically what I'm asking.

Edited 1 time(s). Last edit at 09/29/2017 04:12PM by KM6VV.

no all the pins change. thus the need for a firmware port to the board.