Exchange of information between devices. Communication can be wired or wireless.
0
votes
2answers
114 views
Checksum done without microcontroller
How could I transmit data from a device such as a distance sensor or quadrature encoder with an RF transmitter and also transmit a checksum or will I have to use a microcontroller such as the Arduino?
...
3
votes
2answers
96 views
UHF Phase Modulation
I would like to design a system that produces -10 degrees and +10 degrees phase shifts at 409.6MHz (Basically BPSK).
The way I'm thinking about approaching this is by using a DDS to generate the BPSK ...
2
votes
2answers
138 views
I2C: Is a repeated start between different slave addresses legal?
I'm writing I²C code for an application where I have only one master, but several slaves. In all the datasheets I've read (not only for this project), the repeated start condition is only used to ...
-3
votes
2answers
72 views
Would we have communication theory and systems without trignometric ratio? [closed]
Trigonometric identities happen to be invented for triangles: sin, cosine and through them tangent.
Later at school I learnt that they are periodic and have wave appearance. Than in University I came ...
1
vote
2answers
154 views
Calculating maximum data rates
A channel has bandwidth 3 KHz, signal to noise ratio is 40 dB find maximum data rate for 16 level encoding schemes.
There are two ways to find channel capacity. First one is with Nyquist theorem and ...
1
vote
1answer
161 views
Embedded system engineer's guide to GUI [closed]
For an engineer who solely knows C/C++ for programming microcontrollers, and has no idea about developing fancy GUI application for communication with his embedded systems, Which book and IDE might be ...
0
votes
1answer
234 views
STM32 - PC serial sommunication
What are the available options or ways to connect the STM32 discovery board using UART to a PC via USB or the serial port ? What is the required hardware/cables ?
2
votes
1answer
170 views
FM Quadrature detector - is it the best choice
My input is an FM carrier of 80.00MHz. It is FM modulated with 625kbpsec data. The deviation from carrier is about +/-700kHz. The data never spends more than about 38us in a low state or high state ...
3
votes
2answers
131 views
Is it OK to have data lines and AC in the same multicore cable?
I need to provide the following over sections of 1m multicore cable, totaling around 15m.
240v AC
5v DC
GND
RX
TX
Will the AC cause problems for the Serial data?
2
votes
3answers
78 views
Connecting a simple device with my secured home wifi
I am planning on building a simple device, which retrieves information over wifi. The device shall be as cheap and simple as possible, so it won't have a keyboard or a display.
My question is: What ...
4
votes
1answer
341 views
Digital IQ Modulation [closed]
I have been looking into IQ-modulation and found myself a little confused.
"Traditionally" IQ-Modulation schemes goes something like this:
IQ_Data -> 2 x DAC -> IQ_Modulator -> RF
But I have seen ...
3
votes
2answers
57 views
Rationale for interleaving in G.709
According to the ITU-T G.709 (OTN) specification, a single frame has 4 'rows' and 4080 'columns' of octets, arranged like this:
...
1
vote
1answer
197 views
Use power line to communicate between devices - simple communication
So I am a google programmer getting interested in hardware hacking.
What I want to do:
Use Arduino or a similar microcontroller to control the lighting in my house, of course for as cheap as humanly ...
5
votes
2answers
105 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 ...
3
votes
2answers
167 views
Communicating via USART with an AVR - Input Buffer?
I am currently building a robot (as some of you may know from my previous questions). The current task I a dealing with is that of communication. To keep things simple, assume I have 5 commands to ...
3
votes
2answers
76 views
i2c bus electrical specification
Rise time and Fall time of both SDA and SCL signals are given as 20 + 0.1Cb ns in I2C bus fast mode electrical specifications version 2.1. Cb is bus capacitance and units in picofarad. How do the ...
2
votes
2answers
73 views
Wireless communication with robot
I am making a simple robot, and am using a relatively cheap RF transmitter and receiver to send commands to my robot. Essentially, the transmitter end would send data from an AVR MCU via its UART to ...
0
votes
1answer
38 views
Do I need any specific hardware and/or software to use Mechatrolink for communication?
I googled it and know that it is a communication protocol.
My question is that whether I need any specific hardware and/or software to use Mechatrolink for communication?
Also if possible, please ...
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 ...
0
votes
2answers
534 views
Bluetooth module to have microcontroller communicate with Android phone?
Found couple of fairly inexpensive Bluetooth modules based on CSR chipset that do Bluetooth 2.1 + EDR, and connect to uC over TTL, however the cheaper variety supports only "slave mode", which the ...
0
votes
1answer
930 views
The appropriate code (arduino) of Xbee
Can you tell me what is the appropriate code to send two variables (x,y) from an xbee to another xbee (series 1). I configured them and i can't write a code (because i don't know how to recieve ...
-5
votes
1answer
67 views
Receiving videos via wifi [closed]
I'm working on a electrical board that should receive videos from a server via WIFI. The size of the video is around 100 MB..it will be stored afterwards into an SD card ...so my question is what WIFI ...
2
votes
1answer
340 views
How can I communicate between micro-controller and PC without the use of RS232/USB Adapter?
I use an NXP micro-controller, P89V51RD2, and use a RS232 to USB converter to program it. I'd like to communicate with the computer to send data but without using the RS232 adapter and convert serial ...
3
votes
2answers
138 views
PIC Microchip interface with PC
I have been using USART for interfacing PICs to my PC for datalogging. The problem is that now serial ports are not very common and often you need a USB-Serial adapters which do not always work or ...
1
vote
4answers
1k views
Basic microcontroller + RF transmitter/receiver plausibility
I am a complete beginner (I have only gone through the beginners book to Arduino + done a few small projects). I want to know if it's possible to connect a very basic/cheap microcontroller like the ...
-3
votes
1answer
127 views
How to interface my embedded system to a piece of .net software? [closed]
I have an embedded system powered by a microcontroller. I wanted to design a PC based interface in .net for that system. I am interfacing the Microcontroller with the PC through the RS232 serial COM ...
0
votes
1answer
115 views
virtual light communication
I have to design a project that uses an LED to transmit data and a LDR to receive the data or signal from the LED. But the problem is I have to use two Arduino UNO boards, one for LED transmit and ...
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 ...
17
votes
4answers
8k 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, ...
2
votes
0answers
218 views
Wiring a 1920s intercom to a contemporary door-entry phone
I have recently purchased a 1920s wall-mounted intercom:
I would like to connect this unit to our existing "4+n" door entry phone system, replacing the cheap plastic handset that we currently use ...
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 ...
-3
votes
2answers
77 views
How to send information over large number of client?
I have one master which needs to send information to lots of slave device ~1000 which needs to receive same information.
As I need to power all of the slave device, I was thinking of using same wire ...
1
vote
2answers
259 views
I/Q (quadrature) carrier recovery
I was looking into I/Q demodulation, and when looking into the equations, I realized that the phase/frequency difference between the carrier and the LO in the receiver had an unwanted effect. The ...
7
votes
2answers
807 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 ...
3
votes
1answer
2k views
Error in using Arduino virtual wire
I have this 433MHz RF Tx and Rx pair. I tried to transmit using following simple Arduino sketch, given in the VirtualWire manual.
...
0
votes
0answers
143 views
SSTV on an ARM-based board? (Ex: Raspberry Pi)
I'm wondering if there's an open-source SSTV tool (Or even better, a library) that would work on an ARM-based board like the Raspberry Pi.
I've googled a lot with no luck. The available tools (Like ...
-1
votes
1answer
83 views
How is (non-interfering) data communication possible over the tv spectrum? What is the technology used?
I've heard that FCC-US (Federal Communication Commission - United States) has approved the free usage of TV spectrum for wireless communication. How is it possible to enable such data communication ...
13
votes
2answers
643 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 ...
2
votes
1answer
3k views
Tutorial for USB communication with a PIC18F4550 using CDC framework
I am trying to perform USB communication from the PC to a PIC18F4550 microcontroller using the Microchip PIC18 USB CDC(Communication Device Class) Framework which essentially makes the PIC18, ...
1
vote
0answers
161 views
PIC32 read feedback from UART
I'm using a PIC32MX795F512H to set up a Roving RN-131 wifi module using UART.
I can communicate with the device but I want some feedback whether my commands are processed or not.
I basically need to ...
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) ...
7
votes
4answers
936 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?
4
votes
2answers
139 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 ...
-1
votes
1answer
97 views
Mapping of TDMA frame on to E1 frame
In a GSM network TDMA frame is used to transmit information between Base station and Mobile staton and E1 frame is used as the media to carry information to and in the Backhaul. How is th TDMA frame ...
3
votes
1answer
185 views
Why is RZ-DPSK more nonlinear tolerant than NRZ-DPSK?
In fiber optics, why would RZ-DPSK be more suited for long-haul transmissions over NRZ-DPSK? Is the tolerance to non-linearity due to the power intensity or something else?
-1
votes
3answers
131 views
RF transceiver WITHOUT built-in modulation [closed]
I'm trying to find an RF front-end module for a simple data transmission system of 500 bps.
Since I'm testing different encryptions, I want to modulate the signal, encrypt it, and then transmit it. ...
1
vote
1answer
50 views
Insertion loss and Envelope Delay
Following diagram shows characteristics of typical telephone connection. (Insertion loss and Envelope Delay respectively)
I have been able to understand, that plots are due to dispersive nature of ...
1
vote
1answer
241 views
how much bandwidth does a phone call require and how much is the capacity of a single E1?
How much is the bandwisth requirement for a phone call connection? Considering a non-channelized 1 with 32 time slots how many calls can an E1 support?
Say its 'n'. Does that mean n+1 call will not ...
9
votes
3answers
142 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, ...
1
vote
1answer
95 views
I2C on FFC or IDE cable - interference?
This is a follow-up question on this answer. I need to communicate with I2C over approximately 10cm and I'd like to use an FFC or IDE cable for that.
Earlier, I used an FFC cable to link a segment ...
