An LED, a light emitting diode, is a light source often used as an indicator.

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16 views

wiring diagram for led cube1 [closed]

I want to make an led cube ideally 4 X 4 X 4 I was just looking for some wiring diagrams for a pi b+ I have an idea of how I want to do it. Just wanted to know I am on the right track all I can find ...
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0answers
23 views

Where can I start with Rb Pi 2 [closed]

Just to being, sorry if this is a very nooby question... I have just recently got a Raspberry Pi. I want to switch on and off an LED light with java and the Raspberry Pi combined. Does anyone know ...
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1answer
25 views

How to measure the frequency of the audio output

I was wondering how I can measure the frequency of the audio output of my raspberry pi. Currently I am trying to create a script to control an RGB led to the music that is being played through the ...
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0answers
18 views

can I program gpio led light to flash on particular website?

I have used python to create a program that lights up the led through GPIO on the rasberry pi. I was wondering if and how I could write a python code so that the led light would light up only when I ...
0
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1answer
25 views

Pi is not working properly red led not glowing and green led blinking

I bought raspberry pi b+ some days ago. It worked properly for some days, but now I face a problem the red LED is not glowing and green LED is blinking along with processor is overheated. Can any one ...
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0answers
31 views

Using LED strips (many!) and mutiple power sources wiring up the ground?

So I'm using LPD8806 leds with RasPi, and we are using many many lights and need multiple power sources. With one power source, we wired the negative of the power source to a ground pin on the Pi. ...
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4answers
90 views

How to blink LEDs on/off continually, while continuing execution of a script?

I've connected red and green leds via GPIO and I can successfully switch them on/off using RPi.GPIO - now I'd like to: start an led blinking on/off every 1 second have the script continue its ...
2
votes
3answers
156 views

How to connect 7-segment 4-digits display with Pi?

I would like to connect such a 7-segment 4-digits display (with common anode) to the Raspberry Pi: What's the simplest way to do it with Python for example? Do I need the RPi.GPIO package? Is there ...
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0answers
43 views

controlling 12 V RGB LED strip with raspberry pi

We are trying to control a RGB led strip with a 12 V power supply. The servoblaster does not work. Can you please suggest some other software we can use?
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0answers
73 views

Led connected to pin is always on

I've been following basic tutorials on how to programmatically turn on leds from my Raspberry Pi 2. I'm using a breadboard, and I connect 3 leds, using a male-female jumper from the pins of the ...
0
votes
1answer
50 views

having problem with GPIO switch

I have been working on a project that will allow me to take picture using a switch. So for that purpose i setup the GPIO and all necesseary tools for that code, Python-dev and etc. When i run the ...
1
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1answer
55 views

Raspberry Pi to sync lights to audio input from PC

So I'm wondering if it's possible to make the Raspberry Pi sync lights to sound coming from my PC. I would use an usb soundcard for a sound input and a usual audio cable. Right now I'm running ...
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2answers
141 views

Raspberry Pi 2 - Model B - no boot with Raspbmc

I was trying my brand new Raspberry Pi 2 Model B. I've used the Raspbmc installer to "burn" the image on my micro sd. After I've connected the raspberry to the ac adapter and then to the TV, nothing ...
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1answer
61 views

TLC5947 with a Raspberry Pi

I have been trying to get 8 RGB leds to work with a TLC5947 driver using a Raspberry Pi. But I am not able to get the leds to work. I have tried with the help of fpulse from Wrobbel. But this did not ...
1
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1answer
59 views

problem with LED matrix setup with raspberry pi model B+

I have a raspberry pi model B+ , and an 8x8 LED matrix(single colored) , so I connected 8 GPIO pins to the 8 row pins of the matrix and another 8 GPIO pins to the 8 colomn pins. Note that I am pretty ...
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1answer
42 views

extend the current for PWM LED Control

i am using the raspberrypi to have 2 led's fade up and off. My script works and its ready to go. But i need to get my LED's brighter. Is there a way to extend the GPIO Current of the rasperry pi ? ...
2
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2answers
91 views

Powering several LEDs from GPIO output

I'm currently working on a "rotating cube" project where a raspberry pi will be used to determine which cube face is at the top and any given time using an accelerometer and light it up with LEDs. ...
1
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1answer
68 views

Question about Breadboard positioning

That's my current structure: The short metal of the LED (-) is connected to GND, and the longer (+) is in the port 26. This black "thing" (I don't know the name) is connected to my Pi B+ by a gray ...
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2answers
105 views

Raspberry not booting w/ older Raspbian Release (only Red LED)

I've been trying to install one of the Raspbian Images on this Site: http://downloads.raspberrypi.org/raspbian/images/ So far none of them have worked. I've tried multiple SD Cards and used different ...
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0answers
142 views

controlling rgb led strip via spi and node js

I recently purchased a pi and a string of individually addressable rgb led lights from shenhzen kapata (actually amazon, but they're the ones who sell it) and I'm trying to control it with my ...
0
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1answer
41 views

Switching led over gpio

I would like to switch led over GPIO command. I follow this tutorial: https://projects.drogon.net/raspberry-pi/gpio-examples/tux-crossing/gpio-examples-1-a-single-led/ and I have few problems. Here is ...
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0answers
34 views

controlling a ws2801 led strand

So for a project that I am working on in my free time, I want to create a spectrum analyzer with a raspberry pi which then lights up an led strand according to the music. I have the code working just ...
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0answers
23 views

External FDX and LNK LEDs

I'm making a project where the Raspberry Pi will be mounted inside a closed box, with buttons and LEDs on the front panel. Is it possible to have panel-mounted LEDs that replicate the status of the ...
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0answers
54 views

Hardware for Hyperion

I'm planning to build an ambient lamp, and I like the features that the hyperion has. First, I was going to get these LED's: (WS2801) Addressable Color 12mm Diffused Digital RGB LED Pixels Lights ...
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2answers
115 views

Why are blue LED's glowing brighter than green and yellow LEDs? [closed]

When I connect a blue LED complete with a 1K ohm resistor to pin 17 and turn it on, it gives out a somewhat bright, satisfying light. When I do the same with a green LED, the led light is very dull. ...
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2answers
67 views

I'm looking for a serial input type “polychromatic” LED as an output for my raspberry pi. Does such a device exist?

Forgive any potential neologisms, but I would like to acquire a light that can, say, display 64-256 different shades of color based off of a digital numerical input signal? It can be a usb light, but ...
4
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3answers
584 views

Which addressable RGB LED strips are beginner friendly and Raspberry Pi friendly?

I'm programmer and my electronics knowledge and soldering skills are pretty basic. I want to find a bright, addressable (a.k.a. digital) RGB LED strip which can be attached to RPi and programmed ...
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1answer
65 views

How to decide the amount of resistors for gpio

I will be using raspberry pi for connecting following sensors DHT-11 Digital Temperature & Humidity Sensor for temperature and humidity measurement HC-SR501 PYROELECTRIC INFRARED PIR MOTION ...
0
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3answers
82 views

Power LED is very dim on RPi B+

if I am plugging in the power supply the red power led lights very dim. I found several guides to test the the board with a multimeter but these were for the other revisions, and it seems like B+ is ...
2
votes
2answers
91 views

Driving LED stripes as non-root user

I am using python and the Bibliopixel library (https://github.com/ManiacalLabs/BiblioPixel) to drive a strip of LEDs (type LDP8806). For some reasons, I wanne be able to use this w/o using superuser ...
1
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1answer
237 views

Want to run a simple C program on startup of pi

Im new to linux and the pi . Im stuck with this situation where Iv been trying to run a simple LED blinking C code as a test , so that it will be executed during startup Code works fine when its ...
4
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1answer
94 views

Troubleshoot MCP23017 and LEDs

Anyone have any tips to help troubleshoot turning a simple LED on connected through the MCP23017? I've installed i2c-tools, and smbus. Nothing in my blacklist.conf Added i2c-dev to /etc/modules. ...
2
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1answer
268 views

Is my Pi's GPIO damaged?

I am trying to test GPIO output on a Raspberry Pi, and I am wondering if it is broken. These setups work: 3v3 >> +LED terminal -LED terminal >> resistor >> GND (the LED is unusually dim here) 3v3 ...
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0answers
86 views

RGB LEDs control over Web

I want to control my RGB Leds via Browser and pi-blaster. But I am helpless as a programmer. So I installed node.js and pi-blaster and the pi-blaster.js extension in node.js I made an HTML page with a ...
2
votes
1answer
92 views

Beginner Question - Reading Temperature, Opening Water Valve, Status LED [closed]

I am completely new to Raspberry Pi and would like to hear your input on this project that I need to solve. My question is: What hardware do I need, how would I connect it and how would I solve the ...
7
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1answer
5k views

What do the LEDs on the B+ mean

Not a duplicate of this rPi.SE question, as I'll explain in a moment. GPIO.RPI_REVISION returns 3. As far as I can tell, looking at my B+, there are no LEDs labeled: OK, FDX, LNK or 10M. There are ...
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2answers
90 views

Resistor calulation for two LED

I want to connect two IR LED to the 3.3v output on the PI in series. I need to reduce the 3.3v to 3.0v. What kind and measure should my resistor be? I swear this is not a word problem from ...
0
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1answer
113 views

Rasp PI spectrum analyzer led strip length

I'm new to raspberry-pi and electronics. I was looking to this tutorial: https://learn.adafruit.com/raspberry-pi-spectrum-analyzer-display-on-rgb-led-strip/page-1 Is it possible to build that ...
2
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0answers
196 views

PWM-based controlling an LED-strip using transistors, circuitry problems [closed]

I know there are some similar questions out there, but I'm really new to electronics and unfortunately they didn't provide me help. I want to control a tricolor LED strip (being able to dim each of ...
1
vote
2answers
106 views

Turning LED light on with Pi

I am looking to build a home security camera with a LED light attachment. Many people mention they use a IR Illuminator for the light source which often seem to be DC 12V. I am not sure how one would ...
0
votes
0answers
54 views

PWM to control brightness on i2c LED backpack?

I have something similar to this, it works, but it's too bright! I am aware that LED brightness can be controlled by pulse width modulation, but I don't know if I can safely do that with an LED ...
2
votes
1answer
367 views

Model B+ i2c issues with 7 segment display

I purchased a 4 digit 7 segment display from adafruit and got it working on my old model A running adafruit occidentalis operating system. I recently bought a model B+ and installed the latest version ...
1
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1answer
1k views

Why ACT led is blinking and raspberry not booting?

I have a Raspberry Pi (Model B) with a 8GB SD card, and Rasbpmc installed. Suddenly, one day, it not boot and have these symptoms: Red Led is ON Green Led (ACT) is blinking A rainbow screen is ...
0
votes
1answer
51 views

PiGlow LED went out

(The gist is in bold) I recently got a PiGlow and started playing around with it. When I have the yellow LEDs set at > 200 for an extended amount of time, one of them starts to flicker and ...
0
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0answers
180 views

getting the rasberry pi to controll a tm1802 led strip

Hi i recently purchased a tricolor led strip from radio shack and while they are made for the arduino I am very sure they will work with the raspberry pi. They take in serial data (24 bytes) and use ...
0
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1answer
292 views

ws2801 Wiring Problem?

I recently purchased a 5m long strip of ws2801 leds. I've been trying in vain to get them to light up. During part of my troubleshooting I decided to confirm that I was getting power across the strip ...
0
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1answer
99 views

Need help in my LED Switch REST API [closed]

I would like to seek help on my LED Switch REST API. I have created my own REST API and able to light up my LED when I type in the URL for example: localhost:3030/7/1 to light on and ...
0
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0answers
43 views

LED Printed Circuit for RPI

I have searched high and low for this but I have not been able to find anything close. Basically what I am looking for is a PCB which has a red and a green LED on it and already has the appropriate ...
0
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2answers
111 views

Error on displaying mySQL records in my REST API

I would like to seek help on my REST API. I have finished constructed my basic REST API for my Raspberry PI and able to work now, thanks to you guys. Now I would like to display mySQL database records ...
0
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0answers
141 views

controlling non addressable Led-strips using the SPI

For a project,I need to control RGB lightstrips by DMX and I want to use only 3(RGB) DMX channels.It seems logical to use non addressable lightstrips,for that seems to be the cheapest method (I need ...