The Raspberry Pi is a credit-card sized computer that plugs into your TV and a keyboard. It’s a capable little PC which can be used for many of the things that your desktop PC does, like spreadsheets, word-processing and games. It also plays high-definition video. The design is based around a ...
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4answers
68 views
Best way to control around 250 LEDs [on hold]
I have got the task of coming up with a solution of individually controlling around 250 LEDs. As I would be a complete newcomer in programming an Arduino or whatever else there is, the computing ...
0
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0answers
34 views
How to power an arduino controlled thermostat
I'm slowly working on my home automation system which is controlled from a central Raspberry Pi.
My current project is to control the thermostat / heating from the Pi based on time, temp, occupancy ...
1
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1answer
61 views
General wiring questions: high power LEDs, relay and microcontroller
I think I understand the Raspbery Pi GPIO pins and most of how this diagram below works, at a high level at least.
First question, it's not clear to me exactly how the middle part with the ...
-7
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0answers
42 views
What is difference between beaglebone black and raspberry pi b+ model [on hold]
Please compare the spec and prices of both the models and list out
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2answers
76 views
How to separate two DC voltages in s dual power supply?
I have a dual power supply (Lacie ACLG-51) that supplies both 12V DC and 5V DC with a common neutral (3 wires)
I have used it to drive a little system composed of a Raspberry Pi (5V), USB HUB (5V), ...
-1
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1answer
90 views
Design and build a single board computer [on hold]
I want to learn how to design and build a single board computer like the
Raspberry Pi. I saw a DIY project on Hack-A-Day and design something
like the board in the DIY project but a bit more ...
1
vote
1answer
37 views
How to determine FET switch specifications
I am working on a DIY drone, and I (preferably) need to be able to disconnect my ESCs from the battery via the transmitter (a Raspberry Pi). After looking for solutions for a while, I concluded FET ...
1
vote
4answers
233 views
Noise from switching fans nearby disrupting the I2C bus
I have a RPi controlling a solar system which uses temperature sensors on the I2C bus, the sensors are away from the RPi (20m). The problem is that I have cooling towers and cooling compressors which ...
1
vote
0answers
50 views
Capacitive where is the touch?
I am a newbie in the world of circuits and electronics. But we all started somewhere.
I have this idea about a street sign that should be used as an instrument. All most like a Theremin. Touching it ...
0
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1answer
53 views
Power supply for Raspberry Pi
Before you tell me that the question has already been asked, only similar things have been asked.
I need to power a Raspberry Pi with some electrical equipment attached to it. The Pi needs to run ...
0
votes
1answer
61 views
Power supply for usb devices
I had a question that I was hoping someone could help with. I am building a cluster of raspberry pis to do research on and I decided the best way to power all the nodes was through micro usbs. (I ...
2
votes
0answers
56 views
How to fix RaspberryPi HDMI-DDC/CEC issue while keeping ESD protection?
The RaspberryPi (Type B, all revisions before B+) shows a more or less well known issue with the CEC/DDC of connected HDMI devices. When powered down CEC between the connected TV set and other devices ...
0
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0answers
37 views
Computation capacity for a sound localization and tracking system
I'm working with Raspberry Pi and the Generalized Cross Correlation - Phase Transform (GCC-PHAT), i want to do synchronized sampling on 6 signals of 6 microphone amplifiers.
The Raspberry Pi has no ...
0
votes
1answer
124 views
DIY 5v Solar Panels
In a nutshell : What is a good way to power a 5V project with one-two 0.5 V solar cells?
The motivation is as follows:
My project needs about 2.5-5 Watts from the solar panel. Also,
this project ...
2
votes
5answers
419 views
Simplest uni-directional level shifter (3.3V -> 5V)
I want to drive a WS2801 LED strip from a Raspberry Pi GPIO.
I have connected the MOSI and CLK pins directly to drive the LED but it is not working as the WS2801 datasheet says that a high level is ...
1
vote
0answers
75 views
Is there a Raspberry Pi B+ GPIO header footprint for kicad?
I attempted to make my own using the ModEdit utility in kicad but I'm still having issues adjusting it to the grid even though I followed the standard 0.1'' pitch. It still seems to be off. Is there ...
1
vote
1answer
61 views
driving LEDs via a PI a attiny and TLC5940 (validation) and possible powering issues
at the moment I am planning my first real (big) electronics project. I want to build a LED lamp, that can be controlled by a RaspberryPi (for e.g. programming a binary clock or changing the brightness ...
1
vote
3answers
136 views
Rate my Rasberry Pi UPS
I've made simple schematic for a UPS for Raspberry Pi. It contains a 12V Lead Acid Battery (40Ah), 5V LM7805 regulator and some capacitors. I'm supposing max 1.2A load from Raspi.
Should I add ...
0
votes
2answers
53 views
Connect an ATmega328 to a Raspberry Pi
I've been stuck on this problem for a couple of months now and haven't had much luck finding the exact information that I need. So, I'm currently working on a project to make a handheld raspberry pi, ...
0
votes
1answer
43 views
Raspberry Pi high voltage supply soft-off circuit
After looking at various designs for a "software" controllable power off circuit for a Raspberry Pi computer I decided none of them fit my need so I designed my own. Before I commit it to a PCB for ...
1
vote
1answer
101 views
24V to 5V DC conversion for Raspberry Pi
I'm trying to power several devices off of a breadboard. For simplicity I want to power these all from the same PSU. The highest voltage amongst the devices is 24V. I was looking to use a 24V 2A ...
0
votes
2answers
106 views
Is it possible to power an Arduino Uno with a Raspberry Pi?
I have an Arduino Uno and a Raspberry Pi that I'm using to control some LEDs in a computer case. Power is coming from a Molex connector from the computer's PSU. I want to place the Arduino and the Pi ...
1
vote
2answers
250 views
Can I run matlab on a microcontroller?? and if yes which one?
I am working on a complicated robotics project which involves MATLAB image processing algorithm and LEGO MINDSTORMS interface as well as an Arduino. The system works dependently in a sequence ...
0
votes
2answers
72 views
Faster quadrature decoder loops with Python code
I'm working with a BeagleBone Black and using Adafruit's IO Python library. Wrote a simple quadrature decoding function and it works perfectly fine when the motor runs at about 1800 RPM.
But when the ...
0
votes
1answer
80 views
Solar power monitoring with Raspberry Pi
I want to measure the current and voltage from a set of small solar panels (about 10V and 100mA but not settled yet) using a Raspberry Pi. There will be between 4 and 6 panels.
This project will ...
1
vote
2answers
114 views
Raspberry Pi + Microcontroller for commuting audio input and output (audio matrix switch) [closed]
I am new in electronics and I'm working on a personal project with Raspberry Pi that I need help.
I want to make a board that allows to commute 4 audio inputs (TV, MP3, DVD, FM web) in 4 audio ...
2
votes
2answers
83 views
Interfacing incompletely documented logic signal where resistor affects output voltage level
So I've got this marginally documented 12V logic signal from something I have to regard as a black box that I'd like to interface to a pi or arduino (i.e. c 3V).
I have 3 lines - 0V, +12V and signal ...
0
votes
0answers
64 views
Can I use Cat5e cable to carry 12V and signal for Raspberry Pi project?
I'm doing a "home automation" project with a RPi at the center. It's to do various things including a) controlling lights using PIRs, and b) automating a motorised blind. The blind is opened / closed ...
1
vote
1answer
218 views
Raspberry Pi stereo camera frame synchronization/genlock (video or still image)
I need to frame synchronize a stereo camera for a computer vision application. The synchronization should the best possible, hopefully on a millisecond level. I would like to get about 10 FPS either ...
1
vote
1answer
61 views
Beam sensor or other switch needed for electric blind project
I am designing a motorised blind (powered by a Raspberry Pi) and need a reliable way of detecting when the blind is fully "up" or "down".
I don't want to use a stepper motor, and rely on counts, as I ...
0
votes
1answer
56 views
Powering Raspberry-pi using ESC
Currently I am building a quadcopter with Raspberry Pi and I have four 20A Tunigy Electronic Speed Controller (ESC). I was wondering about could I use ESC's red wire to power my Raspberry-Pi? (tying 4 ...
0
votes
2answers
79 views
How do I active the relays on this relay bank?
I purchased 2 "Mechanical Relay Board, 8 gang, 10A 220VAC, 24VAC 30ma coil" relay banks that I am trying to control from a raspberry Pi. To do this I've built out 2 595 shift registers and I'm using ...
0
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1answer
75 views
Seperate device vs software solution
My apologies, I'm not really sure how to phrase this question. I'm a little confused about what is the advantage of having a separate circuit controlling a module vs connecting the module directly to ...
0
votes
1answer
101 views
Failsafe for home automation with Raspberry Pi
I have a Raspberry Pi driving a home automation system. I have connected a bunch of lights to the network. The GPIOs of the Pi connect to a relay board that switch the lights on and off. What I need ...
0
votes
0answers
116 views
Controlling solenoid valve using Raspberry Pi
I'll start by saying I'm a CS student with almost zero knowledge in electronics.
I want to build an irrigation system which is controlled by a Raspberry Pi (with fancy wi-fi features), and uses a ...
0
votes
1answer
278 views
Arduino: What is the best way to send and receive data with I2C?
I am using I2C to send and receive int values from a RaspberryPi to an Arduino then echoed back to the Pi.
The primary problem I am having is with int values larger than 255.
A secondary problem is ...
1
vote
2answers
115 views
How can I seamlessly switch power supplies?
Quick question, I am not very good with my electrical circuit terminology so I'm not sure what to call what I'm trying to do. When I try to Google "How to switch power supplies" I got inundated with ...
0
votes
1answer
77 views
Controlling a bank of relays
I have a project that requires me to control a set of relays (up-to 24 of them). The current setup is using Wago Speedway 767 field-bus modules. I'm just ramping up so I have to either figure out how ...
0
votes
1answer
273 views
Potential project: Wireless Security Camera with the Arduino Yun
I have been following Arduino and Raspberry Pi projects closely for a while and I am pretty keen on giving one a go. I have no real electronics assembly experience but can program.
I have chosen the ...
0
votes
0answers
52 views
Spurious interrupts using switches on a Raspberry Pi
I have two switches connected to GPIO pins on a raspberry pi. One side of each switch is wired to +3.3v. The other side is connected to an input pin via a 330 Ohm resistor, and each input pin has a ...
1
vote
2answers
50 views
Connecting RaspberryPi & Leonardo-voltage divider needed?
According to this article when connecting a RPi to a Uno a voltage divider is needed because of the voltage difference.
Does the same apply to a RPi and Leonardo?
0
votes
1answer
36 views
Connecting RaspberryPi to leonardo
Can any RaspberryPi-Arduino experts tell me what are the best options of sending data from the RPi to a Leonardo given the following
1- running raspbian on the RPi
2- running a Python script on ...
0
votes
1answer
69 views
Avoding repeated queries while working in a WSN set-up of Coordinator-->Repeater-->End Device , when Coordinator and End device are in Range
I am working on a WSN set-up. I posted a question earlier on the same. I had a another question with respect to the same. My question is while working in broadcast mode, if Coordinator and end ...
1
vote
2answers
191 views
Transistor Ohms
I've built the circuit in the schematic below to control my TV, the D1 and D2 LEDs are the two mini LEDs from this IR Extender:
I've cut it below the female headphone jack and I'm using my ...
0
votes
1answer
111 views
Coordinator + Repeater Xbee + End device configuration
I am trying to work on a Xbee based solution for transferring data from with in a specified area.I am using Xbee865LP for the same project.
Now what i want to implement is Make one device act as
...
2
votes
2answers
215 views
ATmega328P running on CR2032 has issues with timing/sleep code as voltage depreciates over time
I have an ATmega328P running at 16 Mhz on CR2032 with a few sensors and radio for about a week now. It started out at 3+ Volts and is currently measuring at 2.96 Volts. At present, I am not using ...
2
votes
2answers
119 views
Using the raspberry pi to measure multiple electrical circuits
I am looking to use the raspberry pi to measure the power consumption of multiple household electronics and record the information to analyze later on. However, I'm not sure if it's possible to ...
3
votes
2answers
265 views
Can I use 74HC14 or NPN transistor instead of MOSFET as level shifter
I have SN74HC14 or BC548 / 2N2222 transistors. I need level shifter for I2C between arduino and RPi.
Here's simple circuit from the internet
Problem is I don't have any MOSFETs. Can I use NPN ...
1
vote
1answer
138 views
Two or more different regulators connected to one battery
I want to make batteries provide power to both a micro controller (Raspberry Pi) and a 4x4 LED matrix. A simple circuit diagram is shown below. (only one LED is drawn in the fig. But regard it as LEDs ...
0
votes
1answer
79 views
Best way to emulate network switching on PCB
I'm interested in wiring up some Raspberry Pi Compute Modules together on a custom PCB board with DDR2 SODIMM connector interfaces.
...
