[BCwanderer]

I would like to contribute some ideas for a unipolar, pic18252 based design.
I have been working on the board design.
I have not started coding as I have been working on the layout.
The microproccesser is a pic18252 because I have some on hand.
Resonator is 20 mhz
I am driving the FETs with a high current driver chip.
Microstepping will be by using a resistor ladder with 4 micro outputs to input into the comparator that controls the current in each leg.

The board layout is still under review as there may be some bypass caps to add. Values of resistors on the layout are not right. They will be fine tuned when calulated.

When the unipolar unit is working, a bipolar unit will use similar coding.

I am throwing it out for ideas.
Maybe someone has done this before and has ideas that will shorten the learning curve.

Layout and schematic attached (forgive the non-technical layouts - I am still new at this)

Schematic reloaded in larger size