10 mbit ethernet

fredag den 2. december 2022 kl. 23.50.27 UTC+1 skrev John Larkin:

use an ethernet to spi module instead

A quarter mile would be great, like out to a jet engine on some test stand some distance from a building.

People could use fiber links and local switches, but a good long run of CAT6 would be nice.

A couple of sites, like Cisco, say that 10baseT is good for 100 meters.

10Mbit ethernet can do 500m on rigid coax "10Base-5", so it's probably not a timing problem, just attenuation and distortion 10M uses Manchester coding which puts the most of the information in the 10-20MHz band, doess cat6 signifantly outperform cat3 in that band?

I would expect that NEXT would make boosting the signal at the source impractical, but maybe there's a way to have in-line amplifiers

fredag den 2. december 2022 kl. 23.50.27 UTC+1 skrev John Larkin:

We've done that in the past, with a Lantronix module, but it's clumsy to use and expensive and EOL.

Pity the 2040 chip doesn't have a MAC.

(did you get my email?)

Do you have a link?

Ah! understood.

lørdag den 3. december 2022 kl. 16.32.03 UTC+1 skrev John Larkin:

using lots of cpu resources to bit bang a phy is also a bit clumsy, and you'll still need an IC anyway

$9.95 IC maybe a few $ more than just a phy

yes, thanks for the heads up, I rarely check that email

A quarter-mile is 400 meters, so 100 meters isn't going to cut it.

Of wired 10 Mbit enet, only 10BASE-T1L would work. Don't know if it's still on the market. Maybe, but only for old design. The industrial world has gone to fiber.

Well, not quite: Analog Devices still makes the chips:

.

Look here for other options:

.

Joe Gwinn

Cool.

I ordered a couple. They messed up by not making it easy to remote a USBC connector. Pico Pi has test pads for USB.

If we use that in our (hopefully many) boxes and it goes EOL, we could (with a bunch of effort) design an equivalent and drop them in.

Modern switches - even many of the inexpensive ones - are programmable with several options. One of the usual options is configuring one of the ports to function as a monitor port to sniff on traffic on other ports. There are usually options to look at incoming and outgoing traffic separately.

Did not know that, thanks! The switches here are not very new and quite inexpensive and I can't see how I could talk them into doing that (via which interface etc.) but just knowing this is a possibility is enough, I'll find out if I need it. So far I have the 10 Mbps hub which has several RJ-45-s and a coaxial line and I still can put behind it what I need to snoop at.

You need to look for "managed switch" and "port mirroring".

John

Yeah, but that's the spec for 100baseT also.

As for quarter-mile, you'd be better off using a crash cart, battery or generator and rack of electronics, that's off the grid.

Unfortunately not. I can see in the history that this was in 4/2014 and it did cost €65. No longer available, however.

If you happen to have a 89441A, you can open a BSD style socket on it over Ethernet and write or read from there. It simply accepts / answers GPIP interface text strings.

I have written a program that makes many FFTs over n octaves, collects the data and uses gnuplot to create a 7 decade FFT with log x-axis. The right display for phase noise. C source, runs on Linux in my case. There is also a mostly completed GPIB solution with a USB dongle. My program developped problems over the years with the socket interface. It turned out that you must seek() explicitely when changing the direction of data flow, and Linux started to enforce that.

Gerhard

Am 03.12.22 um 23:00 schrieb whit3rd:

No wonder, they cannot wait forever for collision detection.

Gerhard

Thanks Gerhard. I've used a similar type of adapter for my 89441A for many years, but it gave up the ghost recently. I've been looking for a replacement but the choice seems to be quite limited, and the price of them seems to have shot up.

I've just bought a CentreCOM 210TS MAU transciever for my one, they can be pickup up used for about £15.

I have one with a dead main power supply board. What's wrong with yours?

Cheers

Phil Hobbs