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Re: UDP Terminal Protocol

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On 12/14/2016 11:50 PM, Robert Wessel wrote:
> On Wed, 14 Dec 2016 15:09:13 -0700, Don Y
> <blockedofcourse@foo.invalid> wrote:
>
>>> Physically, the idea would be to replace the serial port with an
>>> Ethernet port.  It would be nice to be able to still connect without
>>> any network infrastructure at all (beyond, possibly, a crossover
>>> Ethernet cable).
>>
>> It might be interesting to consider putting serial port *and* ethernet
>> on the same connector (I'd have to consider the hardware consequences
>> to see if there's a "cheap" way of doing so).
>
> It somewhat depends on the connector.  RS-232 and Ethernet signals
> won't damage each other's ports, so some incorrect connections are not
> harmful.  If you stuck with a standard RJ-45, and 10/100 Ethernet, you
> have four unused pins, which is likely enough for the RS-232 side. You

I was thinking more in terms of *sharing* conductors between interfaces.
See my previous '"On-line" 100BaseTX hardware diagnostics' post as
its along the same lines -- using a second I/F to leverage the existing
*wiring* of the first in the event of a failure of the first.  I.e.,
ethernet has failed but can I still exploit the existing WIRING
to talk to other nodes -- albeit at a crippled rate.

The flip side of this is allowing either interface to appear on
a single connector, moving the "user's choice" into the
cable with which he connects to your device (one terminated in
a DB9/25, the other in an RJ45)

> could then use a standard twisted pair Ethernet patch cable for the
> Ethernet connection, and a special cable for the serial side. While
> the RS-232 pins would be connected to the far device (typically the
> switch) in the Ethernet scenario, the extra pins should not get used,
> since the device won't negotiate anything faster than 100Mb, so the
> remote side should ignore anything it sees on the other four wires.
>
> A problem with that is that usually the inexpensive way to get the
> RJ-45 connector onto your device is to get a jack that integrates the
> magnetics.  And those tend not to make the extra pins available.  So
> you'd probably have to use discrete magnetics.
>
> If you were willing to go to a less standard connector (perhaps an
> RJ-50 - aka 10P10C), you'd have enough signals for handshaking on the
> serial port as well, but you'd need custom cables for both connection
> types.  And of course you'd need separate magnetics.
>

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UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-13 04:23 -0600
  Re: UDP Terminal Protocol Dimiter_Popoff <dp@tgi-sci.com> - 2016-12-13 17:10 +0200
    Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-14 13:33 -0600
  Re: UDP Terminal Protocol Grant Edwards <invalid@invalid.invalid> - 2016-12-13 15:16 +0000
    Re: UDP Terminal Protocol upsidedown@downunder.com - 2016-12-13 18:51 +0200
      Re: UDP Terminal Protocol Grant Edwards <invalid@invalid.invalid> - 2016-12-13 21:13 +0000
        Re: UDP Terminal Protocol Clifford Heath <no.spam@please.net> - 2016-12-14 09:05 +1100
      Re: UDP Terminal Protocol Rob Gaddi <rgaddi@highlandtechnology.invalid> - 2016-12-13 13:23 -0800
    Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-14 13:28 -0600
      Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-14 15:29 -0700
        Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-15 00:34 -0600
          Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-15 01:10 -0700
        Re: UDP Terminal Protocol Les Cargill <lcargill99@comcast.com> - 2016-12-15 21:52 -0600
          Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-15 22:00 -0700
      Re: UDP Terminal Protocol Paul Rubin <no.email@nospam.invalid> - 2016-12-14 15:22 -0800
        Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-15 00:00 -0600
      Re: UDP Terminal Protocol antispam@math.uni.wroc.pl - 2016-12-15 01:49 +0000
        Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-15 00:17 -0600
      Re: UDP Terminal Protocol Grant Edwards <invalid@invalid.invalid> - 2016-12-15 02:06 +0000
        Re: UDP Terminal Protocol Paul Rubin <no.email@nospam.invalid> - 2016-12-14 21:09 -0800
          Re: UDP Terminal Protocol Grant Edwards <invalid@invalid.invalid> - 2016-12-15 17:38 +0000
        Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-14 23:58 -0600
      Re: UDP Terminal Protocol Les Cargill <lcargill99@comcast.com> - 2016-12-15 21:49 -0600
      Re: UDP Terminal Protocol Morten Reistad <first@last.name.invalid> - 2016-12-24 16:10 +0100
        Re: UDP Terminal Protocol Grant Edwards <invalid@invalid.invalid> - 2016-12-24 18:53 +0000
          Re: UDP Terminal Protocol Theo Markettos <theom+news@chiark.greenend.org.uk> - 2016-12-25 13:45 +0000
            Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-25 11:44 -0700
  Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-13 12:53 -0700
    Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-14 14:03 -0600
      Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-14 15:09 -0700
        Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-15 00:50 -0600
          Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-15 11:01 -0700
        Re: UDP Terminal Protocol Morten Reistad <first@last.name.invalid> - 2017-01-15 16:08 +0100
      Re: UDP Terminal Protocol upsidedown@downunder.com - 2016-12-15 15:08 +0200
  Re: UDP Terminal Protocol wzab01@gmail.com - 2016-12-14 13:16 -0800
  Re: UDP Terminal Protocol upsidedown@downunder.com - 2016-12-15 12:56 +0200
    Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-15 11:06 -0700
      Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-26 16:34 -0600
        Re: UDP Terminal Protocol upsidedown@downunder.com - 2016-12-27 07:45 +0200
        Re: UDP Terminal Protocol Don Y <blockedofcourse@foo.invalid> - 2016-12-26 23:00 -0700
          Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2017-01-03 18:48 -0600
  Re: UDP Terminal Protocol Les Cargill <lcargill99@comcast.com> - 2016-12-15 21:42 -0600
    Re: UDP Terminal Protocol Robert Wessel <robertwessel2@yahoo.com> - 2016-12-26 17:21 -0600

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