Re: EHP External Hardware Proposal

Hi, reply in text,

Brian Bartholomew wrote:

> From: Brian Bartholomew <bb@...>
>
> > Keep it simple and do not reinvent the wheel.
>
> > To make an external multi-axis, coordinated controller board is a
> > significant undertaking.
>
> What's the upper bound on per-unit cost where the "external printer
> controller" approach ceases to be attractive?

Well I never planned to replace the printer controller hardware, my approach would make it possible to "talk" to the existing
hardware using the serial port.
See previous posting on the subject.

> As you approach
> $1K/each (a price which must include development costs), you can
> replace custom hardware with an entire standardized PC running
> standardized EMC over RT-Linux, and talk to it from WinNT over
> ethernet. Commodity PC cycles are some of the cheapest available. If
> EMC/RT-Linux is a pain to set up, why not just fix *that*?

Sure anything is possible. But my original complaint was about the EMC being nail down to Linux... and tax money doing it.. but
that's another subject.
It appears there is not real standard for G-Code, just bits and snippets everywhere, some committee has folded and appears not
to have done a good job.. See previous postings about this...
Perhaps tax money would be best spent on make a standard fro g-code.. There are enough cnc programs available and no need to
gild the lilly...
So Matt Shaver replied and there it all started... I suggested that I had already had plans for external RS-232 controlled
hardware much Like Flash Cut and that I would do it myself. Then several people jumped in and it seems like there is some
interest...
In a nut shell, I can't see any reason to make a cnc g-code type of program be limited to one OS... RS-232 is ubiquitous and is
easy to write code for...
A simple external RS232 controlled interface that can use the existing Step and direction driver hardware is what I planned..

I don't see running Linux to then running Windows NT with a network to run a cnc program as a good solution... that's BS


hansw