Exchange of information between devices. Communication can be wired or wireless.
19
votes
9answers
5k views
Software to create timing diagrams
In my professional life, I sometimes need to create timing diagrams for UART/SPI/etc protocols. However, I cant find any good programs available. Do any of you recommend any programs for this that ...
17
votes
4answers
7k views
USART, UART, RS232, USB, SPI, I2C, TTL, etc. what are all of these and how do they relate to each other?
As a novice electronics hobbyist, I have heard these terms and more being thrown around everywhere. At its root, I understand that they are all based on communication between devices, computers, ...
13
votes
2answers
598 views
transmitting 5v signal over a long cable
I'm seeking for help here as I need a reliable answer to this. I need to get an input signal (low frequency 5v digital pulse), to a micro-controller from a ...
13
votes
2answers
420 views
Why not use a ferrite bead around an RS-232 cable?
This is from the instruction manual of a printer:
As you can see, one is not supposed to wrap the supplied bead around the serial cable. What is the reason for this?
12
votes
1answer
951 views
Why are USB devices slower than 480 MBit/s
Motivation
With a signaling rate of 480 MBit/s USB 2.0 devices should be able to transmit data with up to 60 MB/s. However today's devices seem to be limited to 30-42 MB/s while reading [Wiki:USB]. ...
11
votes
3answers
1k views
Why do people use AT commands in serial communication?
I need to know why people in embedded systems use AT commands?
When I have asked people say that it is a standard.
So my question is: What does "AT" means? Why do people keep saying it's a standard?
...
10
votes
9answers
5k views
Injecting a communication signal over DC power supply lines
I'd like to be able to daisy chain multiple devices using just the power supply wires and then inject a communications signal over the power lines to turn it into a half duplex network.
Are there any ...
10
votes
7answers
2k views
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) ...
10
votes
3answers
1k views
Selecting a network layer over CAN bus
I am planning on using CAN bus in an industrial automation application, however I'm having a hard time deciding how to implement the network layer. Does anyone here have any recommendations for a ...
10
votes
4answers
293 views
Sharing and Notating Schematics?
So a friend and I were talking about schematics at work and how we can better communicate among us and our co-workers. I know Kortuk had asked a question previously that was similar, but that question ...
9
votes
6answers
3k views
Wireless communication between more than two Microchip PIC microcontrollers
I would like to create wireless communication between Microchip PICs for my simple project.
It's actually an one way communication but there is one server and more than one client (about 2-4, all ...
9
votes
3answers
141 views
Communication among briefcase halves
I'm building a small laptop-ish device in a briefcase. Imagine the green wires aren't there. The LCD half lies somewhat deeper in its case than the keyboard part.
For now, testing and programming, ...
8
votes
5answers
555 views
What is the most popular embedded serial bus? [closed]
I'm designing an embedded device that I would like to make interoperable with third party peripherals through a serial bus. Should I choose SPI, I²C, or some other bus?
The peripherals will be ...
8
votes
4answers
1k views
How long between Arduino digital pin and IC?
My current project involves using 74HC595 shift registers to control an LED display, however the display could be up to 5 or so metres away from the Arduino board. The plan is to use some DB9/RS232 ...
8
votes
4answers
949 views
What is a good communicaton device among teensy and arduino besides “XBees”
I have been using XBees to communicate my teensies so far.
However, as you know, XBees are really expensive and when I want multiple devices to communicate with each other, I have to pay for several ...
7
votes
4answers
830 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?
7
votes
6answers
4k views
Wireless communication over long distances
Would like to communicate between an Arduino and a PC but over a
distance of 2500+ feet outside in the open, wirelessly. What would be
the best way of doing this? The communcation devices I have ...
7
votes
4answers
405 views
Communication between microcontroller and separately powered PCB
On one board I have a microcontroller with one power supply and on another I have a Flip Flop with a separate power supply. I want to connect a pin of the microcontroller to the reset pin of the flip ...
7
votes
2answers
781 views
Dual-SIM phone, do they use 2 GSM modules ? Anyone has high level schematic?
As an slight extension of my project, I am trying to see if I can improve connectivity resilence by using a dual-SIM approach. Dual-SIM phones (or Tri-SIM, quad-SIM phones) are quite popular in many ...
7
votes
3answers
730 views
Using a LED to transmit data
I am curious about the possibilities offered by LEDs to transmit data over a short range (2 or 3 meters), and what maximum data transmission rate can be expected from carefully chosen, but ...
6
votes
9answers
1k views
What are the ways I can make my circuit communicate with a computer?
I am a novice at electronics hacking. I would like to know how I can make a circuit communicate with a PC. Take for example, a simple circuit, with one LED and a switch. The switch on the circuit ...
6
votes
3answers
1k 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 ...
6
votes
3answers
358 views
Information regarding DC wander
I was just going through a text book on digital communication where something related to ac coupling was mentioned.It was mentioned that if a long stream of one(1) is encountered at the receiving end ...
6
votes
2answers
3k views
Is CAT5 cable good enough for RS-485 vs “true” RS-485 cable
I have a serial comms project coming up. A number of boards with RS-485 interfaces need to communicate. Date rate is 57600bps and cable length will be less than a few hundred feet.
Will shielded ...
5
votes
8answers
979 views
It's been more than 10 years (since I designed hardware with RS-232), and we're still using RS-232?
Are there any alternatives to this ancient yet still popular way of communication?
5
votes
6answers
2k views
Hyper terminal equivalent in windows 8
I need to do some communication between 8051 micro-controller and PC . There used to be a hyper terminal for this purpose in windows XP. I m using windows 8 now. So can anyone suggest me some ...
5
votes
2answers
936 views
Measuring the phase difference between two signals
I'm looking for an analog method of measuring the phase difference between two signals operating at frequencies in the range from (0 - 20 MHz). I'm wondering if there's an IC that does that or a ...
5
votes
3answers
272 views
Ethernet connector and transformers
I'm working on an Ethernet connection for a PIC18F4620 with the ENC28J60. I found a useful article here, with a schematic:
I see I need transformers between the RJ45 connector and the Ethernet ...
5
votes
3answers
206 views
Cross-CPU Communications
So - I have a little situation. I have a MC68000 as my system's main CPU, and a 68008 as my sound CPU to interface with a YM2612 and my RGB video generator. Right now, I'm just going to stop the sub ...
5
votes
3answers
745 views
Connecting two phone handsets to talk
I am hacking some old phones into my arduino project. I am currently controlling all of the ringers, dials, and hooks through my board.
At a certain point, I would like to connect the two handsets ...
5
votes
2answers
99 views
i2c external pullup kills communication
I am using an MCP23017 (which shouldn't matter tho) to extend the number of GPIO pins of an arm based linux computer using i2c-dev bitbanging. It all works fine with wires of a few centimetres.
The ...
5
votes
3answers
295 views
Information content of amplitude modulation versus single-sideband transmission
An amplitude-modulated radio signal with carrier frequency C, which includes frequencies from 0 to F, will use output frequencies in the range C-F to C+F, or a total bandwidth of 2F. A modulation ...
5
votes
3answers
509 views
Rather complicated sensor network
I was working on a project recently and it was the first one which was involved enough to make the sensor networking complicated. In the end, I think the communication was the bottleneck in terms of ...
5
votes
1answer
107 views
State of the art for turbo decoding
I am currently taking an online course on probabilistic graphical models. In the section on belief propagation (BP), specifically loopy BP, reference was made to Robert Mc Eliece's 1988 paper Turbo ...
4
votes
2answers
376 views
How does GPS calculate time
How can a GPS device give exact timing even when the number of available satellites are zero?
I'm monitoring GPS data using VisualGPS.
4
votes
2answers
232 views
How are high-speed serial signals processed?
High-speed serial links such as Gb ethernet, PCIe, Firewire, etc support bit rates that suggest signalling frequencies far in excess of typical clocking speed of typical chips. I am wondering how ...
4
votes
3answers
456 views
UART receiver clock speed
I was trying to understand UART fundamentals.It is understood that
It is an asynchronous communication protocol and hence the TX and RX clocks are independent of each other
The data reception is ...
4
votes
3answers
553 views
How can I make a device that will remotely disconnect an Ethernet port?
In some environments it can be helpful to have the ability to turn off an Ethernet port remotely. One case of this is in a public building where you might have a computer kiosk using the port once a ...
4
votes
3answers
1k views
Implementing a CAN protocol layer in software
Background
I'm developing a project which will require the modest microcontroller specs of:
8 12-bit, 10kHz ADCs
1kB of RAM
48-QFN or smaller footprint
20kbps daisy-chainable noise-resistant and ...
4
votes
1answer
448 views
connect my rc car controller with my computer
I am new to hardware. For my first project, I want to connect my RC car controller with my computer so I can control my RC car in my PC.
What kind of things (hardware, cables, tools, as well as ...
4
votes
2answers
4k views
Power line communication principles
What are the principles of implementing Ethernet over power lines ?
Is it reasonable/possible to create an Arduino shield which will provide both power & network ? (properly isolate the "dangerous ...
4
votes
1answer
175 views
What is Telemetry?
What Is telemetry? I understand that telemetry is used for measuring, transmitting and receiving. I have two questions:
Is my assumption correct or not.
Where is telemetry used and what is its main ...
4
votes
3answers
106 views
Phase locked Loop in Demodulation
Can someone please clarify how a PLL works and how it can the result is used to deduce phase?
My understanding is that a PLL is used to demodulate in situations when the demodulator knows the ...
4
votes
2answers
2k views
Digital input to mobile phone headset port?
This seems to be a common smartphone project, but I haven't seen circuit diagrams with explanations.
What filter network (or resistor network, or other buffering circuitry) should be used to connect ...
4
votes
2answers
327 views
What electric part is on this manhole cover?
Here's a photo of a manhole cover
The letters form the word "ТЕЛЕФОН" ("telephone" in Russian in ALL CAPS).
What is on the picture in the center? Perhaps it is some part that should be associated ...
4
votes
1answer
96 views
Modulation And Other Communication Terms
Could somebody explain the concept of modulating a signal? It's such a broad term I never really understood what it meant.
Are phase shift, frequency modulation, and amplitude modulation all ...
4
votes
2answers
136 views
How to produce clock signals with data on serial port
I am designing a Serial to Parallel converter with PIC16f84A micro-controller. Where I am going to use pin RA0 for data input, RA1 for clock input and RB0 to RB7 for parallel data output from MCU. Now ...
4
votes
1answer
129 views
What frequency/band lends itself to interstellar communication? [closed]
Silly question perhaps... but I got to thinking after reading that the Voyager is now almost out of the heliosheath.
What frequency/band would be suitable to communicate across stellar systems; say, ...
4
votes
3answers
278 views
How to read/generate phase-shift-keying (PSK)
I'm trying to reverse engineer a piece of electronics that seems to be using ~1Mhz differential phase shift keying to send a signal over a 2-wire line that's also used for low-voltage power.
So ...
4
votes
2answers
168 views
How can I add ECC to my packets?
I have been looking into using LDPC's in some of my projects and have had some questions come up. Currently my structure looks something like this:
I am then able to have hardware wake when it sees ...
