Need Help!- G code to Stepper interpreter

[ellasaro]

So here's the thing...I've recently got my hands on a CNC router...and I've been trying to develop my own software to "translate" Gcode into stepper pulses. But I still dont know how to aproach it...for instance, if I want to represent an arc...

1) do I calculate all points in the arc and then generate a sequence of instructions in order to represent them as best as posible?

2) or do I "play" with the motor frequencies in order to get the arc I want...?

Im I being clear? Thanx!

[george4657]

Stepper drivers require a pulse for each increment of travel. For example if steppers set for .01 mm per pulse then you need to send 100 pulses to move stepper 1mm.
This means you have to calculate every point on the path to the resolution of your cnc drives. You then have to send pulse to each axis at the same time to move all axis to the required result.
For example at .01mm resolution to move in a straight line 1 mm in X and 2 mm in Y you would send pulse to Y only then a pulse to X and Y to move X .01 mm and Y .02mm you would repeat this 100 times to move X 1mm Y 2mm.
On top of this you need to time the pulses to have motors run at the desired speed.

George

[doorknob]

I haven't actually looked into this, but since EMC2 is open source, and it must incorporate the functionality that you are looking for, perhaps you could look through the source code and see how it is done there.

EMC Documentation Wiki: Installing EMC2

[ellasaro]

OK! I´ll look into it...If I make any breakthrough worth sharing, I will...Thanx everyone...

[dogsop]

You might also want to check here.

http://reprap.org/wiki/Darwin/Arduino_GCode_Interpreter

This is a g code interpreter written for the Arduino. The code may give you some help in understanding the basics of converting g code to stepper commands and would probably be easier than diving into the EMC2 code.