Tri Duino Stepper
This is a stepper driver using an ATMEGA168 for three steppers.
It takes step and direction from your gcode interpreter
(in this case another ATMEGA168 running 5-D on Arduino)
and drives three stepper motors accordingly.
(There are only 2 steppers in the pic because that all I have but it is set up & tested for 3.)
(The code is crude and simplistic but I have not been programing long & it DOES work)
There are no libraries needed to run this, it really is just as simple as it seems.
Future development should integrate Two-Wire Control (see:) http://www.tigoe.net/pcomp/code/circuits/motors/stepper-motors this will free up 6 pins allowing the extruder to be included.
--Glasshopper 02:04, 21 November 2010 (UTC)
The schematic seems to show the ATMEGA168 driving 3 ULN2803A or ULQ2803A Darlington array chips. That implies that it's driving unipolar stepper motors.
It appears Fairly Simple to substitute 3 L293D "quad half-H driver" chips, in order to drive (more common) bipolar stepper motors.
Unlike all-in-one designs, this design seems to support mix-and-match unipolar, bipolar, and DC motors.
It appears Fairly Simple to substitute discrete transistors and diodes for the driver chips, in order to drive far higher voltage or higher currents (or both) than any of the all-in-one designs can handle.