The tag has no usage guidance.

learn more… | top users | synonyms

-1
votes
1answer
34 views

Converted from ms per int to Hertz [closed]

I am trying to convert from ms per int to Hertz. I have found that my system takes 0.2313ms to transfer one 32 bit interger. Based on this answer Difference between Hz and bps I have divided my ...
2
votes
3answers
116 views

Connecting a RJ45 MagJack

I've made a few things now using a RJ45 jack and a separate pulse transformer. To make the design smaller i'm looking to use a magjak or a RJ45 connector with the pulse transformer built in. The jack ...
0
votes
1answer
36 views

Locating the Origin of 2.4GHz RF Transmissions

Is it possible? How would it work? Consider IEEE 802.11 (aka.Wi-Fi); for instance. There's such an incredible amount of devices out there, measuring and reporting WLAN AP signal strength (RSSI, RCPI, ...
2
votes
0answers
68 views

can i interface profinet protocol to ethernet interface?

i have a profinet device and an Ethernet port which is dedicated for KNX protocol. can i connect my profinet device to this Ethernet port?
1
vote
1answer
62 views

CAN bus physical layer configuration for more than two devices

I am designing a CAN bus for a light electric vehicle, likely using an Arduino CAN bus shield or similar. Using a single D-sub cable it's obvious that two devices could be connected together. The ...
0
votes
1answer
469 views

How do I fetch data from the internet with a GSM module using GPRS? [closed]

Recently I have built a device using Quectel (GSM/GPRS module) interfaced with Atmel MCU. It will control another device using SMS received by that GSM module. Now I am trying to connect it to the ...
-1
votes
3answers
130 views

How large of an embedded system would be needed for a small internet host? [closed]

In the "Internet of Things" there is a push to incorporate net capability on appliances and household object to make then more user friendly. If trying to make a device which can be controlled through ...
-3
votes
1answer
213 views

How a modem really works? [closed]

I really searched a lot and couldn't find a detailed answer(s), what happens when the Network Interface Card sends a Ethernet frame to the modem? Does the frame directly go inside modem's cpu or ...
0
votes
1answer
273 views

How to design PoE splitter for Mode A and B

I would like to power my device via PoE, but I do not know which mode (A or B) is provided by the 802.3af power sourcing equipment (PSE). How should I design a splitter to accept both implementations: ...
0
votes
2answers
31 views

How is the capacity of link more for single network link

In networks capacity_of_link = bandwidth*propagation_delay My doubt is how can a same wire carry multiple signals? Is is because the wire is very long (still the wire can be either high or low). I ...
0
votes
4answers
371 views

Will having two antennae at the receiver give better reception?

I have a 300mbps router with two antennae (tp-link td-wd8968). I'm building a PC and looking for a wireless network card. I have seen seen cards with a single antenna (150mbps) and cards with two ...
1
vote
1answer
111 views

Can we consider that ethernet or RS-232 (RS-485) networks have no ground connection between the two ends of each cable?

This is for a huge home theater. I have a power transformer that converts 380VAC between two legs of a 3-phase power system down to 230VAC, with a center-tap of the secondary being our "neutral" for ...
1
vote
1answer
299 views

Carrier Wave in Wired Data Networks

I know this must be trivial for many... Which are the main reasons why line data is not modulated/demodulated in normal enterprise wired networks (in the sense that discrete voltage levels are used)? ...
2
votes
1answer
418 views

Link integrity test pulse vs carrier signal

Ethernet uses a refinement of ALOHA, known as Carrier Sense Multiple Access (CSMA), which improves performance when there is a higher medium utilisation. When a NIC has data to transmit, the NIC ...
4
votes
2answers
160 views

Two analog power planes for same voltage

I'm designing a board with LAN8720 and LPC1768. LPC's ADC and LAN's magnetics connections require analog 3.3V power. Should I separate these two analog power planes with a ferrite as I separate it ...
1
vote
2answers
399 views

How ADSL Demodulates (restores the order) the signal for dummies

I am not an electric engineer so sorry for questions that might miss some fundamentals. I am trying to understand the ADSL modem. The ADSL modem sends the data over different frequencies in ...
0
votes
2answers
235 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 ...
2
votes
1answer
847 views

SFP pin requirement

I have a question regarding SFP pin requirements. The SFP pin descriptions can be found in the standard document found here. I'm currently designing a high speed LED transmitter and PIN-TIA receiver ...
1
vote
1answer
153 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 ...
1
vote
1answer
111 views

Is USB a switched network?

I recently explained to someone why USB before 3.0 must use polling as opposed to interrupts here. Basically, from my understanding of I2C, USB is also a master slave architecture sharing a cheap 1 ...
4
votes
1answer
212 views

What ultimately determines the speed of electrical media

I have heard several myths about this. Some have said "thicker wires mean faster speed" which I don't believe. Others have said different voltages and others have said higher frequencies. Take Coax ...
2
votes
4answers
971 views

Lightweight Arduino network comms

Is there a lightweight networking framework to facilitate network communications between Ethernet/Wireless enabled Arduinos and Linux/Mac/Windows PCs? Implementing something like being able to read ...
0
votes
1answer
82 views

Are Data Cards simply L1 (Physical Layer) Devices?

I was just wondering, how many levels of the TCP/IP (OSI) Stack reside within a modem or a 3G data card and other similar networking devices? These devices do have a physical (MAC) address, which ...
1
vote
2answers
1k views

How to setup a development network for the ENC28J60 on XP?

I'm working on an ethernet connection with the ENC28J60. During development, I'd like to connect the chip to my computer directly (i.e. not via a gateway). This ...
3
votes
4answers
2k views

Smaller alternative to RJ45 Ethernet connector

I am trying to minimize space usage for an enclosure that holds 48 boards with a RJ45 connector for Ethernet communication on each board. The boards work well with 10BASE-T (2 pairs) connection to a ...
0
votes
1answer
2k views

Problem connecting UART Wifi Module to PC

As refereed to my old question ( Connect UART WiFi module to PC ) which has been solved that days, I have a UART Wifi module ( this one ) and unfortunately I have problem again ! The point is, this ...
-4
votes
1answer
108 views

Connecting SATA to SATA [closed]

Is it possible to use the SATA interface to write data to it by PC and use the bus to transmit the data to another receiver SATA board ?
10
votes
4answers
18k views

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?
-1
votes
4answers
9k views

difference between voice and data services?

What is the difference between the voice and date services. I have read that for voice services T1/E1 frame is used and for data services a frame with a standard header and payload nd tail is used ...
5
votes
3answers
5k views

difference between throughput and bit rate?

Throughput and Bit rate seems to have the same meaning and also have same unit of bits per second. Then what is the exact difference between throughput and bit rate?
3
votes
1answer
5k views

+ and - meaning in Tx+ and Tx- in cable pairs?

Tx and Rx are required in Computer networking, used in Cat5 or Cat5e or Cat6 cable? What does +(plus) and -(minus) sign mean in cable pairs for RJ45
2
votes
1answer
13k views

How to stream Arduino-based camera to HTTP server?

I'm designing a simple Arduino-based robot that would be capable of streaming an A/V feed (small color camera and microphone) over the Internet to a URL (my web server). I would be using an Arduino ...
0
votes
1answer
184 views

What's the best comunication protocol for a sensor network?

What's the best comunication protocol for a fast and cheap wirelless sensor network? Is it one of these? WirelessHART IEEE 1451 ZigBee / 802.15.4 ZigBee IP 6LoWPAN Other
1
vote
2answers
7k views

How to build a ethernet HUB?

I want to build a simple as possible ethernet HUB. I'm new to electronics (just made few arduino robots/projects but no big stuff). I don't know where to start, can someone please explain me how it ...
0
votes
1answer
624 views

Mesh network with high data rate on 868MHz

I need to create a wireless network with high expactations to redundancy and security, making my choise fall on a mesh type network. Between the nodes I should be able to transfer video or at least ...
1
vote
2answers
2k views

Arduino Networking

I want to connect Arduino UNO boards using an Ethernet LAN network. There will be one Master and others will be slaves which are connected using an Ethernet switch and a router. I want to know how I ...
0
votes
1answer
147 views

Switch port maximum output power [closed]

I have a switch who have not the power over ethernet capability. I want to power very small devices with the power available on the utp cable. Do you know the max value (HP 24 ports switch) ? ...
7
votes
1answer
12k views

How do I connect an Arduino to a landline?

How do I connect an Arduino to a landline telephone wall outlet? I'm thinking of home automation, something like: I call my house, and after a few rings the Arduino picks up the phone The Arduino ...
2
votes
1answer
2k views

What does the M/M in RJ45M/M mean?

I have what I've been told is one of these cables, but not sure what it means.
7
votes
1answer
3k views

Half-Duplex Twisted Pair ethernet - which pair?

Which ethernet pair is used for half-duplex signaling? In full-duplex ethernet, 1,2 does TX; while 3,6 does RX. In half-duplex, in theory, only one of them is needed - which one?
4
votes
5answers
11k views

Internet vs Serial communication

Ok all the mouse movements, USB connections and other PC peripherals such as printers ect. are via what is called serial communication. One bit per time... So far so good. But when it comes to TCP ...
0
votes
1answer
326 views

Tiny wi-fi module on one board with ALU and memory?

I am looking for small and cheap wi-fi modules and I want to know, what are the current best results in this area. Also, I would like to know, if it is possible to seamlessly integrate such modules on ...
3
votes
2answers
4k views

Connect UART WiFi module to PC

I recently bought a UART WiFi module (this one) and configured it (wireless configuration method) with right SSID but wrong password (and I don't know what it is). The problem is that I can't reset ...
3
votes
3answers
1k views

56k Single Chip Modems

I'm currently working on a project that's intended for getting old electronics that access networks through the use of a phone line to access the internet. To do this, I'm emulating a simple phone ...
-2
votes
1answer
844 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 ...
2
votes
1answer
248 views

EtherCAT topology and timing constraint question

I'm trying to understand how EtherCAT works. The Wikipedia page says that data is processed as the packet passes through the device. Does this mean devices must be linked in a string formation? ...
1
vote
2answers
2k views

How to setup Arduino on secure wifi network?

I'm thinking about an Arduino project that involves having an Arduino host a basic web server and then connect to a wifi network using a wifi shield or something along those lines. You could then ...
-1
votes
1answer
378 views

voice transmission over ad hoc [duplicate]

Possible Duplicate: why there is a need to have voice - ad hoc network in inter vehicle communication system rather than using a “typical radio transmitter & receiver” we ...
-3
votes
1answer
156 views

why there is a need to have voice - ad hoc network in inter vehicle communication system rather than using a “typical radio transmitter & receiver” [duplicate]

Possible Duplicate: how to ad hoc networking mode using WiFi in vehicles We are making inter-vehicle communication system. So, we are looking at using WiFi Ad-Hoc networking mode (with no ...
7
votes
3answers
5k views

What does the “posted” mean in posted PCIE transaction?

What is the etymology of the word "posted" in "posted PCIE transaction"? I've worked with PCIE and I understand the difference between "posted" and "non-posted" PCIE transactions, but I don't ...