RE: EMC compatible computers

[Dave Lantz <dlantz-at-armorholdings.com>]

my math puts it at (aprox) 1/2 the par-port speed (ECP=2MB/sec) 10 base t =
10Mb (bits!!!) /sec divided by 8 = 1.25 MB (bytes)/sec, 100baseT would give
you 12.5 MB/sec and gigabit (over copper cat 6 wire) would give you
125-250MB/sec.  The hard part for me to figure out was that there are 8 bits
in a byte...---dave

-----Original Message-----
From: Dave Engvall [dengvall-at-charter.net]
Sent: Monday, January 13, 2003 2:52 PM
To: Multiple recipients of list
Subject: RE: EMC compatible computers



Jon,
Did I miss  something. Isn't 10 Mb ethernet about as fast as the parallel
port?

Dave Engvall

-----Original Message-----
From: emc-at-nist.gov [emc-at-nist.gov]On Behalf Of Jon Elson
Sent: Monday, January 13, 2003 10:31 AM
To: Multiple recipients of list
Subject: Re: EMC compatable computers





John Sheahan wrote:

>sorry for the abbreviation  GbE == Gigabit Ethernet
>often run on fibre - which may be appropriate for noise reasons here.
>
>I don't see the extra speed as a bonus for this app.
>
>
>
Note that ALL ethernets, thick-wire, thin-wire and twisted-pair, are
electrically isolated
by transformers.  If there was no other traffic on the ethernet segment,
I think even
10 Megabit/sec ethernot would work for this application.  100 MB/S would
definitely
be sufficient.  With proper attention to keeping the protocol simple, I
would think a
message to each axis drive would only be a couple of bytes, so each
message could
be just tens of microseconds long.

Jon