Re: PC based CNC system architecture

> > Wally K wrote:
> >
> > Mike, i think the problems with Jons soultion for EMC and stepper
> > control is as follows.
> >
> > Jon please correct me if i am wrong.
> >
> > 1) It is a closed proprietary system.
>


>Jon Elson wrote:
>
> Not necessarily closed. I'm not sure I'm willing to give out the
> FPGA design, but I'd certainly give out the complete details
> of the hardware/software interface, in other words what the
> registers look like from the CPU end, sample programs, and
> hopefully the working code will become one of the options
> of EMC.
>

Wally K. replys:

If you give out the complete details of the hardware/software
interface and what the registers look like from the CPU end, sample
programs, and the EMC code. I think that would go a long way to
remove the stigma of a closed system. I will not ask you to give up
your FPGA design if you do not want to. But i would ask you to sell
the programmed chip for others to use in there designs.

> >Wally K wrote:
> > 2) Jon is building what he wants with no input from the group.
>
>Jon Elson wrote:
>
> Well, I had another customer, and the encoder counter and DAC
> (for servo version) are completed already.
>

Wally K. replys:

This was kind of what i was getting at. You have made a specific
design for 1 customer and now everyone has to live with those wants
and needs.

> >Wally K wrote:
> >
> > 3) it will be fairly expensive. From memory $350.00 or so.
>
>Jon Elson wrote:
>
> The particular customer wanted nice Phoenix Contact plug-in
> terminal blocks, and some other stuff that ran up the cost, also
> needed differential input option, etc...
>
> A different design should be able to be done using the same basic
> chip such that the entire counter and rate generator would fit on
> one board. I think the only other part would be the crystal
> oscillator. We also did a fancy 8-slot motherboard for these
> cards, but again, there are much cheaper ways to go, like
> eliminating the gold card edge fingers.
>
> These prices were based on buying 15 PC boards, first time
> (so it incurs the setup charge) and parts for about 5 of each
> board. Even small increases in volume make a big difference,
> especially in the PC board cost.
>
> Jon

Wally K. replys:


Jon you have been with this group far longer than i have. From your
experience with this group wouldn't you say the people here range
from thrifty to cheap (not that there is anything wrong with being
either).

After reading Matt Shaver's post about selling this unit for $800.00
to $1000.00 i darn near fell off of my chair. I would say with that
price Matt has put this control out of reach of at least 90% of the
people that would want it.

I would really like to see your schematic of this control with the
sections needed for stepper control marked. I would like to see if i
could make a new layout and or make different component choices for a
low cost stepper control.

If you start releasing the information you said you would in number 1
above i think people will show more interest in this project and lend
assistance and support.


Wally K.