Re: [CAD_CAM_EDM_DRO] Re: Lost Steps => time for microprocessors!

Alan Marconett KM6VV wrote:

> Jon,
>
> Is the Spartan chip an FPGA? Or a BIG CPLD?

It is a true FPGA, 5000 usable gates equivalent.

> Perhaps you could supply a
> reference source for parts, info and "compiler". Do we need to spend
> gobs of money for the compiler, or is it freely available?

Why would you want to recompile the part? Why can't you just get the
PROM
bitstream from me, or just by the prom from me?

> Are any
> available in DIP style packages, for prototyping?

No, I am stuck using the SMALLEST Spartan, at 68 pins, because I don't
want
to get into 208-pin devices!

> I'll pester my son at
> UCSD and see what gate array stuff he was doing. Would you want to
> give
> us a run-down on what is planned for the board and what it's goals
> are?
> if too early or not a good idea, I can understand.

Well, I have already designed a 4-channel, 24-bit encoder counter, with
fast-EPP
interface all on one Spartan XCS10 part. It has logic for handling the
index pulse
and presetting the counters. It will take differential or single-ended
encoders,
with or without the index pulse.

Using the same chip, I have come up with the idea of putting 4 24-bit
recycling counters
in a chip, with a similar interface. The computer would set the number
of clock ticks
to count before putting out a step pulse. The step pulses (and
direction signal) would
also be used to generate a 2-phase signal, which could be used to drive
a phase
input stepper driver, or to feed to the encoder counter for position
feedback.
Or, you could use a real encoder on the motor to keep track of position.

Jon