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.

learn more… | top users | synonyms

-2
votes
0answers
12 views

Unmanaged Ethernet switch silicon?

I need to add an unmanaged Ethernet switch circuit to my PCB, but I can't find any usable silicon, not even with 100BaseT. Am I missing something? I don't want to have to connect it to a ...
0
votes
2answers
66 views

Ethernet signals

I have an end of an ethernet cable but I don't know where it goes. I want to see if it is connected to a device at the other end. Looking at the pinout you have a TX+/TX- and an RX+/RX- pair of ...
0
votes
0answers
46 views

Ground Plane, Bypass Capacitors and Differential Pairs

I've placed a KSZ9031MNX Ethernet PHY on my board, and am now trying to get power routed to it. The digital side will merely be annoying to do, I think, but I'm at a complete loss on the analog side. ...
0
votes
1answer
48 views

Collision detection on ethernet coaxial cable

On ethernet coaxial cable, how collision is detected by the sending device? I was told by someone that it is related to high electrical current and the difference between the sent frame and the ...
0
votes
0answers
47 views

Read and write FPGA registers via USB or Ethernet

I'm working on an FPGA project on an Atlys Spartan 6 board. I'm programming it in VHDL. I have two 32 bit registers, one for output, the other for input. I need to be able to, respectively, read and ...
1
vote
1answer
42 views

AVR Embedded Webserver + Time

I have the task of implementing an embedded webserver (using ATMega328). Broadly, the system would provide the following functionality Allow user to change system parameters using the web interface ...
0
votes
1answer
40 views

L2 Bridge over Asynchronous Serial line [closed]

I am using pppd (in linux) to send ethernet data over a serial line to another computer. How can I preserve L2 headers while sending Ethernet frames over serial line? It seems the ppp protocol sends ...
0
votes
1answer
56 views

Ethernet chip with integrated tcp/ip stack [closed]

I would like to ask what Ethernet chips are popular for an embedded webserver project. Features needed ... integrated tcp/ip stack support ntp protocol php support Basically the main purpose of ...
0
votes
1answer
22 views

Trouble bridging connection between my Pi and my laptop's WiFi

I have been trying to get this working for a while now and still no luck. I have Googled and Googled till my eyes hurt and everything I try won't fix it. I have sharing disabled on both connections, ...
-2
votes
1answer
68 views

Chat through serial port [closed]

I have completed software part but need help in hardware side. We are given few components and asked to do communication (chat) between two PCs. Components list is: USB to TTL converter Ethernet ...
0
votes
0answers
13 views

Arduino Ethernet Shield: May I connect it to a PC connected to the internet via wifi? [migrated]

I have an Arduino Ethernet shield. May I connect it to a machine that´s connected wirelessly to the internet in order to get the arduino into the internet? Or do I need to connect it only to a ...
1
vote
0answers
44 views

Wake On LAN to PMIC

I'm a connecting a WOL interrupt port of the PHY (an open drain port) to the ON-OFF port of the PMIC of my device. The idea is do a reset of the PMIC and then I'm going to turn on the MCU from a ...
0
votes
2answers
124 views

Why is propagation delay of ethernet cables unaffected by cable length?

I did some searching on how propagation delay in ethernet cables is affected by the cable length. The answer seems to be that the delay is negligible until the cable length reaches a kind of threshold ...
2
votes
2answers
105 views

Problem with Ethernet PHY

One of my clients is experiencing problems with a SMSC LAN8710A PHY that is connected to a Xilinx FPGA. The Ethernet link works perfectly when the board is connected to my MacBook or to my office ...
1
vote
1answer
147 views

How important is the number of cores in RJ45 jacks with magnetics

While searching for RJ45 jacks with magnetics (MagJacks) in Digikey, we found that there is a selection criteria which says "Number of cores per jack". Though we have been using MagJacks previously, ...
0
votes
0answers
42 views

Vitesse VSC8221 Ethernet PHY for Media Converter Application

I'm currently designing a media converter board using Vitesse VSC8221. Just as an FYI, the documents for this product are all available at the product page. No NDA is required. When I say media ...
0
votes
0answers
42 views

W5100 Ethernet Module never recieves any data

I am using W5100 Ethernet module (same as Arduino Ethernet module) with Atmega16A to connect to local server (I.P.: 192.168.1.146 Port: 80) created using XAMPP on my own PC. I am able to establish a ...
0
votes
1answer
82 views

RJ-45 with magnetics transformer (Ethernet port) connections

I am working on circuit having RJ45 connector with built-in magnetics transformer. The schematic diagram of mentioned circuit shows following connections with Rj45 magnetics connector. At first I ...
0
votes
1answer
71 views

Make simple 3 port ethernet switch/Hub [closed]

How can I make a simple cheap 3 port Switch? I have 30 10-base low speed Ethernet devices and I want to connect them together, how can these devices connects together with simple Bus topology? ...
3
votes
2answers
410 views

Homemade ethernet hub not working with three computers [closed]

I am trying to connect three computers in one network. I have connected the wires like the photo. I works with two computers but not three computers at the same time. For example, let's name the ...
2
votes
2answers
76 views

Ring Topology Ethernet Backplane - 3 Port 1GbE Switch

I'm doing a thought experiment/napkin design for low cost cluster processor system. Some low cost, high MIPs CPUs chained together on a backplane. My first thought for a backplane is ethernet, because ...
0
votes
1answer
85 views

Best solution for making a LAN with 2 untwisted lines

I need to provide a best solution for establish a LAN for old train carriages in order to transfer low quality video surveillance data. Only existing lines are 2 wires untwisted throughout all ...
0
votes
0answers
13 views

How do I connect my AKM Servo Motor through the Kollmorgan WorkBench?

I have an AKM21C servo motor from NI, connected to a AKD P00306 drive, which is connected to a UMI-7774 board. And I'm trying to connect it through Kollmorgen Workbench, but it doesn't detect a ...
3
votes
2answers
109 views

125 MHz parallel bus in a double 2.54mm header

I have a BeMicro CV low cost dev board from Altera. It features a Cyclone V. FYI: Schematics and gerber here They routed impedance controlled differential lines to some dual 2.54mm standard headers. ...
0
votes
2answers
68 views

Interface two Ethernet (10 Base) devices without 4 twisted pairs cable (Common ethernet cable) and 10 Base-T Filter

I'm autumn and recently working on a project that wants to connect two IC with part: ENC28J60 (that connects microcontrollers (with SPI interface) to Ethernet and LAN Networks) directly in a PCB board ...
0
votes
0answers
85 views

How to config LAN8710A with PHY by STM32F4x7

I am using STM32F407ZGT6. FreeRTOS is running perfectly on board! I have included Ethernet files. According compilation of Windows Commander stating that it was compiled lacked free. But if one ...
0
votes
2answers
323 views

Interference on ADC reading (STM32F4)

I'm using the ADC of a STM32F4DISCOVERY to sample a signal. The sampled values are directly written to the DAC. I tested this and it worked absolutely fine, just as I would expect. Now I wanted to ...
0
votes
1answer
169 views

Media Independent Interface (MII) vs Media Dependent Interface (MDI)

Is my understanding about Ethernet - MII & MDI correct? MII - Media Independent Interface is about the connectivity between MAC and PHY. In other words, it is about TXD and RXD signals from MAC ...
1
vote
0answers
162 views

What shall be changed about stm32f4x7_eth_bsp.c

I am using STM32f407ZGT6. FreeRTOS is running perfectly on Board! I have included Ethernet files. According compilation of Windows Commander stating that it was compiled lacked free. But if one ...
1
vote
1answer
100 views

Retrieving samples from an FPGA using Ethernet

I have a Spartan 3 FPGA for implementing a specific kind of digital modulation. I read the output signal by UART and RS232 but the rate is too slow for following high frequency signals. It was ...
0
votes
1answer
171 views

TCP/IP stack library for ST microcontroller

I'm looking for a free function library, that implements TCP/IP stack for STM32F103CBT7 (Cortex M3) microcontroller. The datasheet of this controller is following: ...
2
votes
1answer
70 views

What is the 1G Ethernet jitter requirements?

We have a Stratix V FPGA on which we want to run a 1G Ethernet PHY and MAC. Because we don't have a readily available 125MHz reference clock, we are considering using a PLL internal to the FPGA to ...
2
votes
3answers
286 views

Is impedance matching a requirement for CAT-5e traces?

I'm building a patch-board for CAT-5e cables, whereby any pin can be re-wired to any other by a set of jumper cables. This is for testing black-box systems where weird things have been done to ...
2
votes
1answer
166 views

PIC for ENC28J60

I am beginner in the microcontroller world, I started to work with PIC MCUs and writing simple programs in assembly. I am interested in simple controlling via LAN (such as switching LED on/off). I've ...
1
vote
1answer
81 views

1000Base-LX or SX Output and Input Requirement Standard

I have a question regarding the 1000Base-LX or SX standard. The question is mainly on the electrical characteristics of the output and input requirements of the 1000Base-X. The standard is based on ...
2
votes
1answer
104 views

Interfacing Matlab with a NI real time target (cRIO 9073)

I currently have a control system implemented in Matlab that controls a vehicle. The tracking is performed using an overhead camera, and commands are sent to the vehicle via xbee. I have now added a ...
-2
votes
2answers
85 views

Probing/monitoring ethernet traffic? [closed]

I'd like to monitore my home network for suspicious traffic. The simplest option would be my small switch, which allows to forward each and any traffic to a monitoring port. But that's too easy... ...
1
vote
2answers
219 views

What kind of tools would I need to analyze 1000BASE-T/gigabit ethernet waveforms?

I'm an EE student and I'd like to get some visibility into the 1000BASE-T Ethernet waveform. My goal is to induce jitter to learn more about real-world error correction, possibly resulting in research ...
2
votes
1answer
427 views

W5100: get MAC address from devices in network? [closed]

I'm using a single Arduino Ethernet Shield with an Wiznet W5100 chip to scan a network for all devices. (Find the project source code on Github). All devices are in the same Ethernet segment. They ...
1
vote
1answer
49 views

Which pins sense collisions at 100BaseT?

Background Suppose I have the following situation... PC with the NIC hard-coded to 100Mbps, Full-duplex RJ45 cable, pinned EIA-568B (not that the colors in the pinout matter) Cisco Catalyst 3560 ...
2
votes
2answers
112 views

magnetics for ethernet PIC18f

I need to add ethernet connectivity to a PIC18f66j60. The datasheets tells about magnetics. But I know only very little about that. Do you know any surface-mount magnetics suitable for this use ? I ...
-1
votes
1answer
111 views

Transformer Operation

I have few questions about transformer operation. One of the main points of the transformer is ground isolation. Let's say if have a transformer in an ethernet transmitter, and my circuit in the ...
2
votes
1answer
378 views

Arduino Hangs when Connected to 220V Supply [closed]

Product Used - 12V 4 in 1 Relay Board (got it from eBay), Arduino Duemilanove, Ethernet Shield. AIM - Control my Room Lights with Arduino. (Home Automation) My Connection - Arduino is connected to ...
0
votes
1answer
58 views

Speed of 1000 Base KR

What is the speed that can be supported with 10G 1000 Base KR. I am trying to understand how many diff pairs are required for TX and how many for RX to support full 10G speed.
2
votes
0answers
334 views

STM32F4Discovery, an HTTP server and a web page on the SD card

I have an STM32F4Discovery board, and I have implemented an HTTP server on it using the LwIP v1.41 stack. I also have implemented a microSD card reader with SDIO and FatFs, and USB FS as a mass ...
1
vote
1answer
49 views

Frame Size and Function

With regards to Ethernet frames, the typical maximum size is 1500 bytes. Jumbo frames brought this up to 9000 bytes, and there was even some Super Jumbo Frames of sizes larger than that. What factors ...
1
vote
1answer
124 views

Interrupts and Arduino EthernetShield

I'm in need of a little guidance in a project I'm working on. Basically, I'll be using two arduinos: The first one will have: 1 RF Link Receiver (linke here: ...
0
votes
1answer
95 views

Multi-drop 100Mbps network? [closed]

We are looking into the possibility to replace our multi-drop SPI (@10MHz) with an alternative solution that allows for more data through put. I've started to look into possibilities of potentially ...
1
vote
1answer
117 views

PCIE reference clock

I recently completed a PCI-E Gen 1.0 line card design. The line card consisted of 4 Spartan 6 FPGAs sharing one PCIE reference clock. Early on in the design there was a decision to solely use the PCIE ...
0
votes
1answer
109 views

How can I prevent monitor black-out when using boosted HDMI over Cat 6? [closed]

Thanks for looking! I wasn't sure if this question belonged in the EE Stack, but after thorough searching, I feel it isn't a question that comes up in normal product use. Background: I recently ...