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.
0
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1answer
245 views
How to connect Ethernet Switch IC with ARM9 CPU
I'm planning to develop an ARM9 based Linux board as an Ethernet wired router device.
I selected EP9302 from Cirrus Logic as the ARM9 CPU and RTL8305 from RealTek as the Ethernet Switch/Hub IC.
But ...
2
votes
2answers
748 views
Ethernet shield vs Wifly shield
I am trying to make a connection between smartphone and Arduino. I found a method which uses an Ethernet shield. Ethernet shield is connected to the router.
I wonder is Wifly shield is also a kind of ...
0
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2answers
282 views
Discrete Ethernet magnetics
Rather than using an Ethernet magnetics component, is it possible / reasonable to simply use individual isolating transformers?
Inside the magnetics component, it's clearly made up of individual ...
11
votes
1answer
255 views
Reasoning behind Ethernet pair order
An Ethernet connector seems to use a surprising choice of signal placement in its RJ45 connector. Does anyone know the reasoning behind:
The decision to make pair 2 straddle pair 1?
Why Ethernet ...
5
votes
3answers
2k views
How important is the shield on an RJ45 connector?
If I am going to use a PCB mount RJ45 connector for 100mbps Ethernet, does it need to be a shielded connector, or can I get away with using an unshielded one?
Is there some standard which deals ...
4
votes
3answers
282 views
Did I Kill My Chip?
I've got an ENC28J60 Ethernet Controller in a circuit I'm building. I was testing it out but when I got to the point of talking to it over SPI with my micro-controller I got utter silence back from ...
2
votes
2answers
394 views
2 Ethernet Ports and a FPGA
I need to develop an Ethernet encryption scheme. All that needs to be done is take the input on Ethernet and encrypt the packets and send them out the output Ethernet. Is there ANY way I could do this ...
3
votes
1answer
423 views
ENC28J60 not getting link
I use the ENC28J60 MAC+PHY ethernet controller (datasheet) in a fairly standard setup as shown in the schematics below.
I can talk to the ENC via SPI, but I cannot get a link-up when I plug in an ...
2
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0answers
905 views
Arduino Uno + Ethernet Shield : 16x2 LCD Not Initializing
I have a 16x2 LCD shield that I have tested to be working fine when connected to arduino uno using the following pin connections:
3: RW
5: EN
6,7,8,9: DATA(4 bit mode)
The contrast is nice and dark ...
1
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2answers
2k views
When connecting to Ethernet through ENC28J60, why use ATmega88 instead of ATmega8?
I know the general differences between ATmegaX8 family (ATmega88, ATmega168, and ATmega328) and the ATmegaX family (ATmega8, ATmega16, and ATmega32).
But I'm confused, as when I intended to work on a ...
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1answer
242 views
Testing an Ethernet peripheral
I have an Ethernet peripheral (manual here) controlled by an STM32. I have to test that the Ethernet peripheral works correctly right after the board is manufactured. Conveniently, there are three ...
2
votes
2answers
111 views
Monitoring software for embedded application
I'm looking for a Windows application to collect data to a host PC from an embedded application (PIC microcontroller).
The communication between host and embedded application is via Ethernet.
It ...
4
votes
1answer
246 views
Ethernet: What is a jabber timeout
I am writing Ethernet drivers for an STM32 chip. (The reference manual is available here.) At various points, the concept of "jabber timeout" appears, and is not explained. A quick Google search ...
2
votes
2answers
653 views
connecting avr microcontroller to the internet
I'd like to connect my AVR microcontroller to the Internet.
I tried the enc28j60 ethernet controller, but I faced some problems with it. Besides I've read a lot about it and found it easy to be used ...
0
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0answers
263 views
HDMI ports and IP ports (spartan-6-atlys / or what???)
I'm trying to develop an HDMI to IP converter, what should I use? I'm considering using the Digilent Atlys with an Xilinx Spartan-6 FPGA, 2 HDMI inputs, and a 10/100/1000 Ethernet PHY, but is there ...
1
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1answer
2k views
using avr atmega32 as web server using ENC28J60 chip
looking for help on making a website on ATMega32 using the ENC28J60 chip
iam searching for more than a week .. i found many already-made projects on this, but nothing worked with me .. iam very ...
25
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2answers
4k views
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.
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votes
1answer
350 views
How network card uses electricity? [closed]
I've read that NICs (Network Interface Controller) send and receive binary data as pulses of
electricity, light, or radio waves.
The NICs that use electricity to send and receive data are the most
...
0
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1answer
99 views
Smart switch for accessing Ethernet cameras [closed]
I'm wondering whether something exists - preferably something already available commercially, or which could be manufactured in quantities of 2-50 without excessive up-front investment - that could do ...
8
votes
6answers
3k views
Arduino or PIC microcontroller?
I was thinking of creating a surveillance mobile robot. And I am having a problem of choosing a PIC or a Arduino microcontroller. The surveillance mobile robot is controlled via wireless fidelity ...
0
votes
2answers
1k views
How cheap could a .NETMF board be w/Ethernet
I'm getting started with .NETMF and was wondering, what is the cheapest .NETMF board could be developed for, assuming it only has an ethernet jack and lwIP stack for TCP & UDP support? The code ...
-1
votes
1answer
296 views
Create router using .NET MicroFramework
I'm really interested in getting started with embedded software development. Since I already understand OS internals and computer architecture, I'm thinking of starting with .NET MicroFramework (mf) ...
7
votes
2answers
1k views
Connecting ethernet to AVR
I am getting pretty familiar with microcontrollers and now want to connect it to the internet. What are the minimum requirements for a microcontroller to be able to do this, specifically, an AVR one ...
-1
votes
1answer
239 views
Need an advice with choosing FPGA kit to be used for wireless application [closed]
I need to implement a Wireless (802.11n) firewall as a FPGA application, so basically what i need is an FPGA kit that can handle the trans-receiver part for me, while giving me the ability to process ...
2
votes
4answers
180 views
Commonly used standard for telephone wires
What type of wires are commonly used as indoor phone lines? I'm curious to know what is their bandwidth compared to my CAT5 cable that I use with DSL modem.
4
votes
3answers
376 views
For remoting 1000Base-T ethernet connector, is it better to remote PHY from magnetics or magnetics from connector?
I'm in need of remoting the gigabit ethernet connector from the main board to a back end board that has all the other connectors. I plan on doing this with a high speed board to board connector ...
4
votes
1answer
301 views
Why is 1000Base-T RJ-45 pinout scrambled instead of having each diff. pair in sequence ?
I need to make an ethernet connection using a cable about 6 feet long to a small and low power gigE camera. Other signals are required (power to camera and hard trigger) and one cable is better than ...
1
vote
3answers
277 views
What is the cheapest way to email someone whenever a button is pressed or a switch is closed?
I would like to be notified somewhere else on the internet every time my door opens at home. If I do this with a magnetic switch, I realize that this is an event that would probably stay under 0.3 Hz. ...
4
votes
3answers
1k views
How do network devices detect whether an ethernet cable is connected?
I have a bit of kit with an FPGA on it which includes an ethernet adapter. I'm trying to diagnose why it's not working and while I do that I've noticed that with an ethernet cable connected to my ...
2
votes
1answer
872 views
Probing ethernet cables with a scope
I'm in the middle of a project that requires writing software that would send some packets over Ethernet every N milliseconds. The ethernet wire would go from a computer to a switch, and then to the ...
1
vote
2answers
555 views
Cheapest way to communicate with a Fez Panda II (or Arduino board)?
I have an application where I will have 30 Fez Panda II boards connected together. They will be spread out over an area of about 100' x 150'.
I prefer TCP/IP communciation, but adding a FEZ Connect ...
4
votes
2answers
364 views
Help with Ethernet circuit
To reduce EMI the datasheet recommends using a LP filter as shown in:
http://ww1.microchip.com/downloads/en/DeviceDoc/39762f.pdf page 219, Figure 19-2.
The filter is made of 56pF capacitor and 120ohm ...
1
vote
6answers
2k views
Is there any way to send serial data over physical ethernet layer with no encapsulation?
I wonder if I can use the physical ethernet layer like a serial port. Is it possible? The case would be reading signals with an electronic device without dealing with networking headers.
7
votes
2answers
1k views
Poor eye diagram, where to start looking?
I'm trying to debug a 100Mbit ethernet board and I'm running up against a problem I'm having trouble trying to resolve.
This is the eye diagram for the transmit pair. The receive pair is very ...
2
votes
5answers
320 views
Looking for a chip to connect to internet and display text
I am looking for a small chip that will be able to connect to the internet and display black & white text. I'd like to program the chip to connect to a remote service and display text accordingly. ...
1
vote
2answers
610 views
Combining netduino with Ethernet Shield
While buying hardware, the Netduino Plus was not available so I bought Netduino and Ethernet shield. These days I have been trying to create and example of web server using Netduino and Ethernet ...
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votes
1answer
2k views
How do i pull variable from Arduino Ethernet-Shield using PHP (Wamp server)?
How can I pull a variable located in Arduino RAM through an Ethernet Shield from my PHP (WAMP) server?
e.g I have variable red_led = 1 in the Arduino, now how ...
2
votes
1answer
2k views
Ethernet: how important is the magnetics topology?
I have some Ethernet issues with a set of boards (6/10 are bad). They're possibly just assembly house mistakes... but I'm very concerned about my magnetics jack.
I could have sworn I saw a example ...
48
votes
6answers
7k views
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 ...
6
votes
4answers
410 views
Is FCC-accredited testing required again if circuit board is placed in a different package?
I am considering enhancing a commercially-available device so that it can be installed outdoors. The enhancement would be to seal the product inside a resin case to make it weather-resistant. The ...
2
votes
3answers
290 views
safe to use an unshielded jack for 10Mbps Ethernet?
I have a hardware device which includes Ethernet connectivity. I have a surface-mount Ethernet jack, with top entry (as opposed to right-angle). Part number is RIA Connect AJS03B8813, if that helps. ...
2
votes
3answers
1k views
Arduino Uno with Ethernet shield is not working
I recently purchased an Arduino Ethernet shield, plugged it on top of my Arduino Uno and loaded up the WebClient/WebServer sketches that comes with the Arduino 0022 IDE, but I could not get it ...
3
votes
3answers
796 views
What does the Arduino ethernet shield connect to?
I am thinking about buying an Aurdino ethernet shield, but I am not sure what it connects to. On the back of my iMac there is a blue plug which goes into the computer, which I think is the ethernet ...
0
votes
2answers
409 views
RTL8188SU datasheet
I am trying to communicate with the realtek RTL8188SU chipset, but I can't find any reference or datasheet. Does anyone have RTL8188SU datasheet?
1
vote
4answers
303 views
USB/Ethernet to a (real) bell based on a signal
I'm a total beginner in hardware, but I'd like to build a piece of material that would make a real bell ring for a specific duration, or eventually instead of a bell, a light that would switch on ...
1
vote
1answer
526 views
How to hook up an Arduino Uno to serial and ethernet
I've got an Arduino Uno and I'm relatively new to electronics / I'd like to connect it to a serial receipt printer and an ethernet switch. For all the research that I've done, I've found a number of ...
3
votes
5answers
375 views
Want to build an ethernet-connected USB or battery powered piezo alarm gizmo — what's a good kit?
The device is supposed to beep loudly if the network is down, a particular port on an Internet host doesn't respond or a socket connection is made on a specific local port.
Is an Arduino Ethernet ...
3
votes
2answers
333 views
Alternating patterns in 8b/10b encoding
I'm trying to evaluate the quality of an 8b/10b encoded data stream (Gigabit Ethernet, 1.25 gigabits/sec). Without doing clock recovery from the data stream, I want to measure jitter (et al) with a ...
3
votes
1answer
1k views
Picotux alternatives available?
I wanted to use a tiny Linux computer to read data from I²C bus. I knew there was Picotux, and I was thingking about buying one.
But the website is down, so I guess there's no Picotux anymore. :(
...
1
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2answers
309 views
Looking for TCP/IP Ethernet <-> RS-485, Half Duplex Device
We are currently using the Wiz108SR device and need to provide this as a consumer ready component with a power supply. We would rather not build and package the powersupply but instead purchase ...
