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

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22 views

Setup a led that blinks via php server

I wanted to blink or just lit up an LED on my Pi GPIO pin via a server/website. I've the resources like Pi, LED, php server etc. I just don't know how to code to connect my Pi to server and control ...
-6
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0answers
27 views

Thoughts on cool illuminated power switch? [on hold]

what do you think of this switch on Kickstarter? I think I'm gonna get one! https://www.kickstarter.com/projects/1312527055/illuminated-raspberry-pi-safe-shutdown-switch
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1answer
37 views

Pi stopped working by itself

I had some fun with the device, configured it as Wi-Fi router and it worked fine for a couple of months. Then hot-spot disappeared and only red LED is now on. I don't have a spare HDMI monitor or ...
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2answers
57 views

What GPIO pins are required to Power RPi? [duplicate]

We are using Raspberry Pi Model B: We used USB connector from PC - confirmed output - 5V, with 2 leads: Connected +5V to Pin 2 Connected GND to Pin 6 on connector - Inserted Ethernet cable ...
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2answers
32 views

How to bring out Status LEDs to be available on enclosure [on hold]

We have developed a product based on Raspberry Pi and currently designing the enclosure. To enable users to understand the status of our device we would like to provide two LEDs. These LEDs would ...
0
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1answer
45 views

Pi4J - Changing GPIOs from and to Input, Low and High

I am trying to create something which uses Charlieplexing, and to use it, I need to be able to turn GPIO Pins to and from different states (Low, High and Input) from what I understand from this video: ...
2
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2answers
60 views

My first breadboard / led

I loosely followed this. I've been studying breadboards for about an hour now, so this is super fresh in my head. My understanding is as follows: 5v power on the +(red) track (white wire) Ground ...
2
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2answers
47 views

L.E.D controlled by IF STATEMENT from variable

I want to control some L.E.D's through the GPIO ports depending on the value of "variable1" which will become a raw input. The problem is, if variable1==70 then both led 12 and 16 with light, but only ...
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1answer
45 views

How can I control the PWM via the sysfs

I want to set the PWM for some tests with a tricolored LED. I want to be able to set it up via the sysfs interfaces but I'm having a very hard time finding any information on how to do this. What is ...
3
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3answers
117 views

How to use 2 x MCP23017?

I need to control 32 L.E.D's individually, now looking through the forum, the common solution is to use MCP23017 chips, as they can control 16 l.e.d's. With that in mind, I would require two chips. ...
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0answers
39 views

multiple PWM for led control

I'm creating a musical instrument based on capacitive sensors and I want to add some color to it. I would like to use PWM controlled LEDs because I want to make them dim and fade away nicelly. My ...
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3answers
93 views

Control 18 LEDs individually? (17 GPIO pins)

Note: I have read Controlling many LEDs with few GPIO pins, but I can't buy additional parts (Degree project) The end result is to make a noughts and crosses grid with 2 LEDs per grid cell. This ...
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0answers
107 views

Unable to control 5V LED strips

Using this addressable LED strip: WS2801 Led Full Color character string matrix screen point source 12mm 5V WS2801 IC Chip, Addressable Color, need for controller. Identify IC every led light, Red- ...
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5answers
239 views

Using one Raspi to control long (>100ft) of 5V LED strip

I am using the below LED strip for accent lighting 5M WS2801 Blcak PCB 32LED 5050 RGB Digital LED Strip Individually Addressable 5V item: nonwaterproof black pcb ws2801 led strips Model: 5050RGB ...
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2answers
63 views

LED strip has R-G-B instead of DI and CI

I went and bought an LED strip which has the following labels +V R G B How does this correspond to another naming scheme I have seen which looks like so: GND DI CI +5V I could use this ...
2
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2answers
85 views

How do I get simple lighting inside a case for my Raspberry Pi?

I'm new to the RPi. I'm looking to put a light inside my RPi case for a glow effect. But since I'm not an electronics guy, I have no idea what kind of an LED I can use and where to put it inside the ...
1
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1answer
56 views

Network does not work anymore

My Raspberry ran for about a year and was a webserver and samba server. Suddenly I couldn't connect to the raspberry pi and ping also didnt work anymore. I flashed a new OS to the sd card but I still ...
1
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1answer
370 views

Controlling Multiple analog RGB 12V led strips

I need to control several (5 to 10) analog RGB strips which have a separate power supply at 12V or 24V. Just like this one for example. I need to control the intensity of each colour channel for each ...
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3answers
88 views

Raspberry Pi - Controller for a light system

I am after some technical help. I need to independently operate 29 lights. (each light must have the ability to turn on/off without depending on other light states) Now I want to do this with a ...
0
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1answer
55 views

controlling 50 piranha rgb leds

I'm a total newb looking for some help. I've got a bunch of piranha rgb leds. I wrote a program using wiringpi, hooked up 10x leds, and it all works fine. However, won't adding more leds be a problem? ...
0
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1answer
772 views

Controlling multiple 7-segment LEDs with few GPIOs

I've got a simple single-digit 7-segment LED working properly (simply using 7 GPIO pins), but I'd like to scale it up to multiple digits and higher power. But I'd like to keep the number of GPIO pins ...
1
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2answers
145 views

Driving Bi-Color LEDs

I have some LEDs that are Bi-Color so if you make a circuit like this: [+]-----[LED]-----[-] you get one color, and if you do it the opposite: [-]-----[LED]-----[+] You get the other color. I ...
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3answers
546 views

Raspberry Pi LED current limit

I've got an Raspberry Pi and I want to control some LEDs. I've read that the maximum current at the GPIO pins should be less than 50mA. But each LED uses 20mA. Does that mean that even three LEDs are ...
0
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1answer
334 views

battery power for RPI and IR LED bank?

I built a simple night vision set up using a model A RPI, pi NOIR camera, and car backup camera monitor. I made a simple infrared light by wiring 4 sets of 6 LEDs in series, so 24 total, let's see if ...
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1answer
331 views

Voltage issues with my Raspberry Pi

I'm having some trouble driving LEDs from my Raspberry Pi, so I started poking around with my multimeter, and the voltages seem very wrong. Compared the the ground port, the 5V0 ports show 4.6 V, ...
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2answers
3k views

Control WS2801 with Raspberry Pi

Anyone has managed to get raspberry pi connected to WS2801 RGB Led Strip? I have followed the connections here at adafruit: and tried to test the LED with pixelpi.py. The pixelpi.py runs ...
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1answer
963 views

Python script failing with AttributeError: LED instance has no attribute '__trunc__'

I am currently bread-boarding two LEDs with 560 mOh resistors connected to the RPi over a ribbon cable that connects to the breadboard with a Pi Cobbler. The problem I am getting isn't with the ...
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1answer
102 views

Controlling the on-board FDX and 100Mbit LEDs with a kernel module

I know that the OK LED can be accessed from /sys/class/leds/led0, but the FDX and 100 are not. I can see from /sys/class/net/eth0/duplex and /sys/class/net/eth0/speed that the files seem to correspond ...
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4answers
1k views

RGB LED resistance calculations

This is my first time doing this, so forgive me for what seems like a very basic thing, I have read through both these articles, and I'm still not clear on the exact math to do. ...
2
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1answer
2k views

Why can't I turn on an LED through Python?

I have an LED connected to pin 11 on the Raspberry Pi header, (also known as BCM/GPIO pin 17, and GPIO0). I have installed the Raspberry Pi Python library according to these instructions. Attempt 1 ...
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1answer
239 views

Why aren't GPIO_22 and GPIO_23 lighting up LEDs? (Beginner)

I'm losely following a traffic light tutorial where the following diagram has been provided: I've followed the diagram, only deviating from the tutorial to use RPi.GPIO in GPIO.BOARD mode.. I had no ...
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1answer
103 views

LED laden show helmet [closed]

Let me start off by saying: I know very little about the interfaces that are going to be used here but I'm a steadfast study and have a programming engineering buddy that not only convinced me to post ...
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1answer
374 views

Raspberrypi won't start. LED's are on

I haven't used my RaspberryPi in month and today I wanted to start it, but my HDMI monitor doesn't get a signal. The LED 'OK' is shortly blinking at the beginning but then turns of. All the other ...
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3answers
421 views

Lighting a LED slowly with GPIO

What is a good way to make an LED turn on and off slowly using a Raspberry Pi? Im trying to hook up an led to become a Tardis lamp, but since the Pi doesnt have ADC/DAC, Im kind of stuck. What are ...
0
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1answer
97 views

what limits the number of LEDs I can connect to the GPIO

if I just want to simply connect LEDs to the +3.3v pin and ground pin, what limits the number that I can connect? for example using green LEDs with a voltage drop of 2.2v, I can only connect one with ...
2
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1answer
283 views

Other hardware for camera slots?

I think the raspberry should get more cool hardware like the camera that works with the slot onboard. I'd love to get a fast RS485 onto this slot because i need all my GPIOs for LEDs. Currently I use ...
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1answer
131 views

How to check if device is turned off

Is there a way to check if the Pi is off, without looking at the chip itself but with a LED or something like that.
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3answers
2k views

Power light but very dim act. No display or network output?

When connecting my pi via HDMI, I am getting no image. I can't see any additional devices on my network when connected via Ethernet. LED panel has a strong red light on PWR, very dim green light on ...
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2answers
2k views

Controlling 400 LEDs from a raspberry pi

I have a client who has several large bronze signboards, each with 100-150 little light bulbs on it, totaling approximately 400 bulbs. The bulbs are turned on and off on a schedule, currently by hand ...
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2answers
160 views

Raspberry Pi LED confusion

I have had some issues with my raspberry pi. I went online to find some videos to try to figure out what is going on. I then noticed that their raspberry pies Have the LEDs OK, PWR,FDX,LNK and 100 (in ...
0
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1answer
687 views

Raspberry Pi Not turning on

I just got a raspberry pi in the mail from element 14. Its a model B. I also bought this SD Card to boot from. When I first put in my SD Card and plugged in my power the PWR led turned bright red, ...
2
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3answers
4k views

Controlling a 12V RGB LED strip with the GPIO

I have an RGB LED strip (specifically, this one - 1 meter's worth) and a 12V power supply to go along with it, since the raspberry pi alone can not power the strip. I am going to be using pi-blaster ...
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1answer
358 views

Raspberry Pi failed to boot, power led remains off

Connect my Pi model B to mac USB port. The power LED remains off. There is excessive amount of heat generated at the component highlighted in the pic. Any idea how to resolve? ...
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2answers
3k views

Controlling many LEDs with few GPIO pins

I successfully completed my hardware "hello world" using this guide: http://www.raspberrypi-spy.co.uk/2012/06/control-led-using-gpio-output-pin/ Now I'd like to move on to bigger and brighter ...
0
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2answers
10k views

Why Isn't My Ethernet Working?

I just got Pi Model B. I downloaded Wheezy on SD card and plugged in all of my cords. Everything works fine except the Ethernet port. The LINK LED flickers for a second while booting up, but then it ...
6
votes
2answers
1k views

How can I turn the lights off on my pi?

I'd like to build a small internet radio out of my pi, but I'd like to use it at night, when the flashing LEDs would be disturbing. Is there any way to disable them?
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2answers
977 views

Connecting blue LED (3.3V)

I've recently started doing basic diode connections (red and green diodes). I've also got blue diodes, but there's one thing that prevented me from connecting them already, namely - the specs say ...
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2answers
1k views

Is it possible to connect an LED directly to the GPIO of the Pi?

I was wondering if it is possible to connect an LED directly to one of the GPIO pins of the Pi? The reason I ask is that, I have read from many sources that if I am not using some sort of break out ...
2
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4answers
3k views

Pwr LED is solid red, OK LED flashes green once, no display

Power is good - I've tested with a voltmeter. According to this link, the SD card image is not written properly yet: The Raspberry Pi cannot find a valid image on the SD card. Check card is ...
0
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1answer
763 views

RPi.GPIO turns pin on at setup

I have an LED connected to a GPIO pin and am using RPi.GPIO to control it. When setting up the GPIO pin, the LED blinks on ever so slightly when being initialized, which I don't want. import ...