Exchange of information between devices. Communication can be wired or wireless.
0
votes
0answers
28 views
Help required performing Single Master - Multiple(upto 16) Slave SPI Communication using MSP430
I am planning to use MSP430F6638 for SPI Communication between a single MSP430 Master and multiple MSP430 Slaves. I am using a 4x16 Multiplexer before each Slave for providing the Chip Select Signal. ...
0
votes
0answers
40 views
Erlang B telecom system (grade of service)
I am bit stuck with an answered question that I found online:
We have an Erlang B system where the total number of served call is 15.48 erlangs. The system contains 23 circuits. The incoming calls ...
0
votes
5answers
144 views
Good RS232-based Protocols for Embedded to Computer Communication
I'm working on a project that involves a good bit of data communication between a remote Arduino and a computer. The wireless connection is through a pair of XBees, so we have a RS232 link between the ...
3
votes
2answers
101 views
How good is coaxial cable?
My question relates to the accumulated AC voltage that will appear on the screen of a length of coax:
If the cable is properly terminated at one end and fed with data (or any signal) at the other ...
3
votes
0answers
59 views
Faulty RS-485 device has irregular effect on neighboring devices in bus setup
I am trying to understand the mystery of how one faulty RS-485 transceiver, in a network bus with several devices, seems to have very irregular influence on its own and its neighbors transmission ...
0
votes
0answers
49 views
Multiplex data and LED pin
I'm looking at performing a chip conversion for the Sparkfun LED RingCoder. The sample code provided with the product works well on an Arduino UNO, but it uses a pin for each I/O - 5 pins for the ...
-1
votes
0answers
44 views
Wake up a node wirelessly [closed]
I have an RF UART module device which is sleeping (master device). I can wake it via a timer and force it connect to any available slave-nodes and talk via RS232. However, I am wasting battery this ...
2
votes
1answer
88 views
Selecting communication between microcontrollers at high temperature
I have been assigned to a project to find the best possible communication between several PCB boards which have microcontrollers for a specific function. I need to have all microcontrollers ...
0
votes
1answer
52 views
why does signal attenuation caused by shadowing vary?
Given a RF sender and a receiver, suppose the obstacles between them are fixed, both their material and dielectric properties, does the signal attenuation caused by their shadowing vary over time? If ...
2
votes
0answers
47 views
why is shadow fading also called slow fading and large-scale fading?
I've encountered several similar claims regarding shadow fading on several books, and have some difficulty understanding them.
(1) Shadow fading is called slow fading because the duration of the fade ...
4
votes
3answers
105 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 ...
3
votes
3answers
154 views
Why is probability theory that important to communication theory?
Since Shannon's paper Mathematical theory of communications, probability theory has played an important role on communications (digital and analog).
I've been checking some course descriptions on my ...
-1
votes
0answers
38 views
Bus and short circut [closed]
I have a problem with some Ultra sonic heat meters and Mbus. As soon as I connect the bus to the level converter the level converter indicates short circuit. If I change the voltage supply to the ...
0
votes
2answers
87 views
Strange I2C behavior: sometime it works, some time it doesn't
I am using Arduino Ethernet with PoE and Arduino Uno boards. In recent days I implemented a working I2C bus by using the Wire library and all it seemed almost to ...
-3
votes
1answer
56 views
Best way to Interface with PC/MAC/iDevices/Smartphones [closed]
What do you think is the best way to communicate a hardware with PC, MACs, iDevices and Smartphones (with Android, Windows Mobile, etc.) ?
We need to make a voice chat (like VOIP) and also exchange ...
-3
votes
1answer
43 views
A uniform scalar quantizer
I have a uniform scalar quantizer with M=4 levels of quantization, and a natural mapping from levels to bits of the 01000110111110 Frame. Is it possible that this ...
-2
votes
1answer
43 views
what are the things to keep in mind when interfacing two digital devices?
what are the things to keep in mind when interfacing two digital devices, e.g FPGA with a dual shock controller or CPLD with a PS/2 Mouse, Microcontroller with an FPGA, FPGA with an external RAM.
One ...
2
votes
2answers
60 views
Connecting two STM32f4discovery boards
We have two STM32F4Discovery boards with Micro USB's for serial communication.
Is it possible to connect two boards to allow communication between them?
Is there is any different hardware other than ...
5
votes
3answers
267 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 ...
-2
votes
1answer
49 views
Choosing a good 4+ pin connector/cable for connecting AVRs [closed]
I'm working on a project where I2C and power is passed between multiple devices and am trying to select a good choice of connector/cable to use between devices which will be daisy chained.
The key ...
1
vote
1answer
26 views
Power delay profile and broadband bus
I came across the following solved question, but I have trouble understanding part of the solution. If anyone could shed some light into this I would be really grateful since this problem has been ...
2
votes
2answers
109 views
I2C pull-up resistors calculation & where to place them
I'm connecting a PIC18F46K22 (master) to a PIC18F4620 (slave) using I2C. The wire between the devices is ~30cm. I'm using 400kHz without slew rate control. Later on, I'll add another 18F4620 on ~5cm ...
1
vote
4answers
165 views
What is the Need for modulation
What is the need for any kind of modulation in order to transmit signals?
-3
votes
2answers
93 views
Free space model (wireless communications)
The received power at a given distance = 1km is 1nW .
Find the received power at a distance of 5km from the same transmitter , using the Free Space Model.
Suppose that frequency is 1800Mhz, ...
1
vote
1answer
99 views
FM Transmitter and transmission
This is an FM transmitter circuit found in Internet Link.
Before doing ,I'm simulating in multisim. Since there is no mic input,I have given sine wave generator
1).What is frequency of wave must ...
2
votes
2answers
67 views
Realizing an flexible, but fault tolerant, infrared communication chain
The task fell on me to realize a wireless, daisy chained communication system. The communication must be wireless, esp. via infrared diodes. The end of the chain is connected to a PC (wired).
The ...
0
votes
2answers
111 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?
...
4
votes
0answers
101 views
Help to identify unknown Sync Serial Bus
Does somebody already seen a sync serial bus communication like that ?
Repeated Pattern :
Detail of beginning :
I fail to identify it...
it look like I2C but :
it have a clock at 2MHz (so ...
1
vote
1answer
77 views
i2c maximum bus speed calculation
This question is based on the Philips I2C specification UM10204.They gave (section 7.2.1, page 56) for calculating the maximum frequency of the bus:
...
-3
votes
2answers
70 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
1answer
141 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 ...
1
vote
2answers
142 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 ...
0
votes
1answer
217 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 ?
3
votes
2answers
91 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
1answer
147 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
128 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?
3
votes
2answers
56 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:
...
2
votes
3answers
76 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 ...
5
votes
2answers
98 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
146 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
74 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 ...
1
vote
1answer
171 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 ...
2
votes
2answers
72 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
34 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 ...
-5
votes
1answer
66 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
302 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
133 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 ...
-3
votes
1answer
123 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
110 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 ...
2
votes
2answers
121 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 ...
