Questions tagged [led]
An LED, a light emitting diode, is a light source often used as an indicator.
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Can the sleep() function take floating point values?
If I try to have my code sleep for an arbitrary non-integer value it appears that the sleep() function rounds to the nearest integer. For example:
GPIO.output(LED, GPIO.HIGH)
sleep(0.3)
GPIO.output(...
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Malfunctioning Raspberry pi 4, red and green led on all the time
My Raspberry Pi 4 won't boot anymore, there is no picture on the monitor, and both LEDS (red, green) are on all the time, they do not blink. I formatted the SD card with SD Card Formatter and ...
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Powering LED strip off a raspberry pi zero - works but lights at end of strip fade
I am powering LEDs off my RPIZero to use as an Ambilight clone. My setup has the LEDs being entirely powered off the GPIO pin 2 (5v)but I have noticed that the far end of the strip seems darker and ...
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RAM Usage of Neopixels: How many can I power with a Raspberry Pi
I am building LED Matrix's with Adafruit Neopixels, and I read somewhere that the amount of pixels you can control is limited to how much RAM you have on your controlling device, in this case, a "...
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lighting up LEDs from suricata security alerts
so I am a Python newbie attempting to write a script that will light up a different LED based on the priority level of the latest security alert added to a log file generated by the Suricata Intrusion ...
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How to use this IR Sensor as LIRC receiver for Rasberry Pi [closed]
So, recently I went to an electronics store to buy an IR Sensor, so they gave me the next one: IR Phototransistor NPN
Then I went online to check how to build this, and to my surprise, I've found ...
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How do I power an IR LED signal that is 50 feet away?
I'm building an IR blaster with an LED that will be wired 50 feet away from the circuit. I'm going to use this 18 gauge wire to extend the LED connection.
I'm using a GPIO pin connected to a BC547b ...
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Adafruit Neopixel 60LED RGBW Strip showing up with wrong RGB color
We are currently using the Adafruit Neopixel RGBW 60 pixel LED strip with our project, and are currently trying to control it. The strip, however, is displaying incorrect colors when trying to ...
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Raspberry Pi with touchscreen - screen turns white and pi restarts when trying to use LEDs
We currently have a Raspberry Pi 3B+ with touchscreen hooked up to a PCB, and are trying to run adafruit neopixel 60led strip but, when we try and send data using their library, the screen turns white ...
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Driving a WS2815 (12V, addressable) LED strip
I am trying to plan what I need to drive a 12V addressable LED strip with the Raspberry Pi (4, likely, or zero, but I want Ethernet connectivity).
I am not sure I understand the WS2815 datasheet (PDF)...
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LED only works when plugged in backwards
My LED only works when it's plugged in "backwards" like the following example:
https://pi4j.com/1.2/images/gpio-control-example.png
My understanding is that the longer pin on the LED should go ...
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Dimming a 0-10v dimmable light
I've raspberry pi 4 and I'm building a project that simulate sunrise and sundown.
I've found that LED - WYZM HBL-100W that get 220AC AND DC 10V, I can dim it by lower or increase DC voltage level.
...
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How to wire a button
O have tried to do this so many times, so many websites, so many books, and it just won't work. I do not know how to wire it so that the LED lights up when I press the button. I'm pretty sure that I ...
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Is it possible to power IR light module from 3.3v GPIO
Welcome,
i've got a question that is bugging me for quite some time lately. I've got RaspberryPi zeroW with ZeroCam camera module (without IR filter). To get it to work in dark I bought IR LED ...
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Piezo Buzzer Driven By Rpi GPIO Problem
I'm trying to light up an LED and play a buzzer noise at the same time. Here is my code so far:
Import RPi.GPIO as GPIO
Import time
GPIO.setmode(GPIO.BCM)
GPIO.setup(7, GPIO.OUT)
while True:
...
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AC mains dimmer dimming 7W LED lamp problem (RpiZero + MPDM V4.1)
I'm trying to dim a 7W LED with a Raspberry Pi Zero for home automation. However it doesn't work as expected.
I followed this tutorial :
https://www.youtube.com/watch?v=wqY4-gHqvZI .
I have the exact ...
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PIGPIO problem with delay on scripts
I am trying to run an old Raspberry Pi 2011.12 as a server to control a RGB LED strip. To this I am using PIGPIO since this is the best solution (RPi.GPIO is software based, which creates flickering). ...
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1
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Why the same GPIO pin is not working anymore?
I was working with a very simple code:
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(24,GPIO.OUT)
GPIO.output(24,GPIO.HIGH)
But after running one time when I am running the code next time ...
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Is there any built in LED connected with GPIO pin?
In Arduino a built in LED is attached with number 13 Digital pin.
Is there any LED like Arduino in Raspberry Pi,which I can use to test my code?
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How to power on multiple LED through 3.3V rail ? (Power supply problem)
I'm trying to use the 3.3V rail to power up 10 LED (20mA/LED).
I read that the raspberryPi could supply until 1A through this 3.3V rail, that's a lot more than needed when all the LEDs are powered on....
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12V Solenoid with Relay doesnt trigger
So I am using 8 AA 1.5V batteries that is wired to my 12V 16 channel relay which is wired to my Rpi.
I want to be able to control 16 solenoids and use the relay as a switch for the solenoids. As far ...
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Turn on a Led with Raspberry Pi
I found this video on YouTube, and I want to try doing the same, the problem is that I dont know how much voltage the GPIO18 has.
Link of the video: https://www.youtube.com/watch?v=86x6NweQsdY
I've ...
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Slight dip on the GPIO 5v line when LEDs are on
I have my raspberry pi set up to do two main things:
control 16 LEDs via 16 transistors each connected to an out pin. The LEDs are collectively fed the 5V from the GPIO.
power a chip also on the 5V ...
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1
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RPI 3B+ 'activity' LED always flashes approximately every 1.5 secs With Buster booted external USB SSD?
Booting my pi 3B+ from Buster on a USB SSD 240G Kingston A400, I now get quick pulsing yellow (green?) activity LED flash bursts, every 1.5 to 2 seconds, during normal operation, even when only the ...
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Massive old LED Sign....powered by Raspberry Pi?
I got this massive 165cm/16kg LED sign: https://www.alpha-american.com/p-alpha-premiere-9200c.html and it seems to be working as far as I can tell when I power it up: https://youtu.be/Msf971cHOQs . ...
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Whole control the green led on RPI 3B+
I would like to learn gpio control on raspberry pi, and now I have a RPI 3B+
I found that the greed led is GPIO29
I think it will work to set the green led on or off by gpio, but at the same time, ...
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Can I drive a custom LED matrix from my Pi
I have an idea for a project, but I am unsure of the best route to take.
I am going to create a custom 11x10 LED matrix (addressable LEDs like WS2812) with the intention of lighting up certain LEDs ...
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Led on before declaring it
Hello I need some help with my leds, I have 2 leds one green and one red. What I want to do is just turn on the green led (and turn off the red) when I press a push button, that is to say all the time ...
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LED Strip on Raspberry Pi Check if its On - Neopixel
How can I check if the one pixel is on or not?
Is there any function for that. I've googled but couldn't find anything helpful.
import board
import neopixel
pixels = neopixel.NeoPixel(board.D18, 17)
...
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A PWM object already exists for this GPIO channel
I have a bit of a dilemma. I am currently using BCM GPIO 14, 15 and 18 to control an RGB status LED using PWM. I have configured my raspberry pi 3 to pull down pin 14 (red) on boot, to indicate the ...
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RPI project Minecraft Server
me and a project partner are running a Minecraft server off of a RPI and connecting via its wireless feature. we wanted to create a python script which would control an LED and toggle it on/off based ...
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Raspberry Pi and car led ground effects
I am about to add led strips to my car. I will have at least 4 zones to start out and might add more.
1. Under carriage
2. Front end
3. External
4. Internal
Doing it now, I will have 4 controllers ...
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2
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What's wrong with my current calculation for an LED panel?
I am trying to understand how much current is required for one LED matrix panel, however, I don't quite understand it in general.
Take this panel as an example. This is an 64x32 LED matrix, and its ...
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2
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Power LED from 3.3V Power Pin without Resistor
I tried wiring one white LED to the 3.3V pin on a Pi Zero W with a 330 Ohm resistor but it's not as bright as I would like. If I wire it up without a resister I get a good amount of brightness. Is ...
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GPIO LED is constantly on. GPIOZero can't turn it off
If power is supplied to the Pi then the LED will be on by default. I've got the LED connected to GPIO pins [4, 6] and the script can not turn it off. I've switch the cables around and that's resulted ...
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Need help with Controlling WS2812B LEDS
I have made a 5 x 5 WS2812B RGB LED matrix to work with my raspberry pi.
I'm trying to figure out how to run several tests from this tutorial:
https://tutorials-raspberrypi.com/connect-control-...
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Connecting jumpercable to gpio pins
My teacher gave me a large group of jumper cables attached to one another.
this might be a stupid question but if it's attached like on the on the bottom picture what is the order of the cables? (...
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Controlling LED strip from GPIO Help?
I have a ws2811 LED strip that I was powering using an arduino, but I want to do some more complicated things with it, and figured my old raspberry pi would be perfect.
So I followed a tutorial online ...
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How to get maximum GPIO output speed in Kernel module?
I'm writing a Linux kernel module on RPi2 to push an array to RGB Led matrix, so I want to have maximum speed of GPIO to reduce the 'flick' when it run Bit Angle Modulation. According to this site, ...
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Problem controlling LED on GPIO3
I need to add a status led to my pi zero w and after taking a look at the pin out I decided to put an led between pin 5 and 6. Please see attached picture. I soldered a blue 0805 SMD led directly on ...
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Risks of powering short LED strip directly from GPIO
I am trying to understand the simplest ways to power a short LED strip of 30 WS281x lights.
Most of the instructions I’ve found mention using a separate power supply for the LED’s, but is it ...
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Turn on multiple output with single button
I'm working on project with single input multiple output logic. The project require two or more led controlled by single button (momentary). the steps are like these :
1. When the button pressed for ...
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2
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turn led off after 5 seconds
i am new with RPi.. can someone help me, i am working on a RPi project.
i am using lcd touch screen with guizero. i create 5 pushbuttons to turn on 5 different led. BUT i cant turn off the LED after ...
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How Can I Make Lights Flash On My Raspberry Pi When A SSH Connection is Active?
I recently got a Raspberry Pi B+, and I have been playing around with it a lot. I want to start a personal project where, when I link to my Pi through an SSH connection from my laptop, I can make a "...
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Are my resistor leds safe
I have the following leds ... ... that I hope to be able to connect to my pi for power and disk activity indicators.
I read some guide that claimed that around 330Ω resistors were needed, but the ...
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3
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Powering 100mA LED
I want to power an 1.5V LED fully and control it using pi. I can only use 16mA per pin and i need 100mA. Can you give me suggestions? I can turn it on with 5V and 35 ohm resistor but not control it. ...
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Pi Camera LED blinking
I have gotten back to using my Model B Revision 2.0 Pi. After starting it up, I noticed the red LED on the camera is blinking (not the Pi itself, that one is solid). When I take a picture, the ...
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Tinkering with environment variables
i want to run my pi headless, and only wire up some switches via gpio to operate it. i want it to monitor 3 switches, and tell if theyre high or low, and react accordingly. it should be launched every ...
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Power indication
I have build a musicbox with an rpi 3+ and added a power button and 2 buttons to turn the volume up and down.
The buttons have LED lighting, I have connected them to GPIO pins but this results in ...
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1
answer
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LED matrix won't light up properly
As you can see it won't light up correctly, why is it so?
Is it possible that there are some issues with common cathode or anode?
I tried using just that smaller one by itself, in a similar fashion ...
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