Questions about the electrical implementation of Ethernet; ask another Stack Exchange for software or protocol questions. Specify the speed as 10/100BASE-T is somewhat different from 1000BASE-T, apart form the speed. Those are copper standards; Ethernet over fiber optical cable is also defined.
Questions tagged [ethernet]
1156 questions
133
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Should chassis ground be attached to digital ground?
I'm working on a PCB that has shielded RJ45 (ethernet), RS232, and USB connectors, and is powered by a 12V AC/DC brick power adapter (I do the 5V and 3.3V step down on board). The entire design is enclosed in a metal chassis.
The shields of the…
cdwilson
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4 answers
Why Are Ethernet/RJ45 Sockets Magnetically Coupled?
As the title says really, why do ethernet sockets need to be mag-coupled? I have a basic understanding of electronics, but mostly, I can't figure out the right search terms to google this properly.
slugonamission
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Why is an Ethernet cable not grounded?
There is no dedicated GND in the classical Ethernet 8P8C ("RJ45") pinout.[1]
Why does the Ethernet spec not include a ground, unlike many other cable types used for interconnecting devices that may both have its independent power source as well,…
mykhal
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20 answers
What is a good microcontroller for Ethernet applications?
What is a good microcontroller for doing Ethernet applications? Or do I just need a good Ethernet library to connect with an Ethernet MAC/PHY?
Robert Deml
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3 answers
what is the difference between PHY and MAC chip
I want to know what is the difference between PHY and MAC chip
user152250
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9 answers
Why is wired Ethernet losing its speed advantage over wireless?
This has been bugging me for a while now. I did a couple wireless transmission courses back in my university days and it's a known fact that wireless transmission is hard. Partly because it's a shared channel, physical objects can be in the way, air…
Francois
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29
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4 answers
Why is Ethernet So Power Hungry?
I was just perusing the Microchip ENC28J60 Ethernet Controller datasheet and saw that the operating current can be as high as 180mA while transmitting and 120 mA typical while active but not transmitting. At 3.3V we're talking 400 to 600 mW of…
vicatcu
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28
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4 answers
Very long distance Ethernet connection for internet and other data (2000 feet)
I am building a house. It's located about 2000 feet away from the nearest internet cable. I had to run our electrical service underground the whole way, and have already installed a conduit for internet/phone cables from end to end with pull points…
Ryan Griggs
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24
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8 answers
Communication between multiple microcontrollers
I'd like to start implementing a system consisting of N microcontrollers (N >= 2 MCUs), but I would like to know the possibilities to let them communicate one with the other.
Ideally, (N-1) microcontrollers are placed inside the house acting as…
user51166
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3 answers
How does a 40 Gbit/s Ethernet interface process packets in silicon?
A 40 Gbit/s Ethernet interface should have a 40 GHz signal on it. How does common silicon IC technology handle such an exotic beast?
My best guess is that internally various parallel busses are used, but I haven't found much on the internals of…
Watson Ladd
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3 answers
Microcontroller with both ethernet and radio onboard?
Does anyone know of any (reasonably low-cost) SoC which combines all of:
Microcontroller (any architecture, at least 4KB RAM/8KB flash)
Radio transceiver (433MHz - 915MHz or 2.4GHz)
Ethernet MAC + PHY
(For a wireless sensor application -…
Toby Jaffey
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22
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3 answers
How is 10G Ethernet physically possible?
10 gigabit Ethernet means that 10 billion bits are transmitted every second, but I don't understand how this is physically possible (let alone 100G Ethernet). The fastest CPUs today only run at ~8GHz, but even if transmission doesn't require a CPU,…
HaLailah HaZeh
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21
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5 answers
Difference between Hz and bps
Does Hz and bps mean same? Can a signal be transferred at rate of say Mbps on a channel bandwidth of few Khz?
sk1
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21
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3 answers
Do magnetics connectors exist?
Conventional connectors, where the plug and socket have metal parts which touch, suffer from the following problems:
Limited mating cycles or expensive plating.
Impedance mismatch (relevant for high speed signals only).
Lack of isolation.
Here's…
Rocketmagnet
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Cheapest way to add wifi to a project
I need low power wifi for a not-very-data-intensive application. What modules or chipsets should I look at? Other than low cost and low power, I have no restrictions. The cheaper the better.
This is for a high volume product, so both hobby level…
Adam Davis
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