Re: [CAD_CAM_EDM_DRO] Re: Was Chopper circuit - Now ver 3.2, G298

----- Original Message -----
From: "Alan Rothenbush" <beer@...>


> Now, to carry this project further, the only "control" logic required over
> and above the PIC to drive the G298 is a comparator.

The PIC16F627 / 628 has 2 built in analog comparators. That's what I used
for my L297
PIC replacement processor on my second generation 10A drivers. So I know the
F628 can replace an L297.

Another processor that is very new is the Cypress PSOC. It has a lot of
analog
and digital features that are programmable and runtime reconfigurable. I'm
using
it in a project at work that has nothing to do with CNC. You might want to
take a look at it. The development kit is cheap and the debugger has some
fantastic features. And you'll need them. The processor has a few warts.

Just for grins, I'm going to do a microstepping driver with it that will use
Fets
for the drive transistors. I think I can even cram a quadrature decoder on
it for
position feedback. That configuration will use up all of it's digital blocks
and most
of it's analog blocks.

later,
Larry E.